ISSN:0003-2654    

DOI:10.1039/AN95378FX025

出版商:RSC    

年代:1953

数据来源: RSC

ISSN:0003-2654    

DOI:10.1039/AN95378BX027

出版商:RSC    

年代:1953

数据来源: RSC

ISSN:0003-2654    

DOI:10.1039/AN95378BP057

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

MAY, 1953 Vol. 78, No. 926 THE ANALYST EDITORIAL THE BERNARD DYER MEMORIAL LECTURE WITH this issue of The Analyst we publish photographs of the Bernard Dyer Memorial Medal. The Council of the Society decided soon after Bernard Dyer died that it would be fitting to commemorate the great services he rendered to analytical chemistry by instituting a lecture in his memory, to be known as the Bernard Dyer Memorial Lecture and to be given every second year, The first of these lectures was given in 1950 by Sir E. John Russell, F.R.S., and the second in 1952 by the Hon. Mr. Justice Lloyd-Jacob, and both have appeared in The AnaZyst. It was intended from the first that the giving of these lectures should be marked by the presentation of a medal to the lecturer, and, accordingly, Mr.T. H. Paget was commissioned to design and produce one. The choice of artist was a very happy one, his work being well known to the world as the designer of the obverse of coins of the last reign, and to chemists as responsible for the Castner Medal of the Society of Chemical Industry. Mr. Paget’s design was accepted by the Council last year, and the medal was struck from it by the Royal Mint. Copies were presented to the first two Bernard Dyer Lecturers on the occasion of the Society’s Biennial Dinner in March, as reported elsewhere in this issue. The photographs we publish are by the Honorary Secretary of the Society. This handsome medal forms a fitting memento both of the occasion of the lecture and of the eminent chemist in whose memory it has been struck.The obverse carries an excellent likeness of “13. D.” in his habit as he lived, and the reverse bears a symbolical reminder of his activities-a ploughed field to mark his lifelong interest in the land, a Kjeldahl flask in memory of his laboratory researches on fertilisers and a full sheaf of corn as an emblematical represen- tation of the benefits conferred on mankind by his life’s work. 261MAY, 1953 Vol. 78, No. 926 THE ANALYST EDITORIAL THE BERNARD DYER MEMORIAL LECTURE WITH this issue of The Analyst we publish photographs of the Bernard Dyer Memorial Medal. The Council of the Society decided soon after Bernard Dyer died that it would be fitting to commemorate the great services he rendered to analytical chemistry by instituting a lecture in his memory, to be known as the Bernard Dyer Memorial Lecture and to be given every second year, The first of these lectures was given in 1950 by Sir E.John Russell, F.R.S., and the second in 1952 by the Hon. Mr. Justice Lloyd-Jacob, and both have appeared in The AnaZyst. It was intended from the first that the giving of these lectures should be marked by the presentation of a medal to the lecturer, and, accordingly, Mr. T. H. Paget was commissioned to design and produce one. The choice of artist was a very happy one, his work being well known to the world as the designer of the obverse of coins of the last reign, and to chemists as responsible for the Castner Medal of the Society of Chemical Industry. Mr. Paget’s design was accepted by the Council last year, and the medal was struck from it by the Royal Mint. Copies were presented to the first two Bernard Dyer Lecturers on the occasion of the Society’s Biennial Dinner in March, as reported elsewhere in this issue. The photographs we publish are by the Honorary Secretary of the Society. This handsome medal forms a fitting memento both of the occasion of the lecture and of the eminent chemist in whose memory it has been struck. The obverse carries an excellent likeness of “13. D.” in his habit as he lived, and the reverse bears a symbolical reminder of his activities-a ploughed field to mark his lifelong interest in the land, a Kjeldahl flask in memory of his laboratory researches on fertilisers and a full sheaf of corn as an emblematical represen- tation of the benefits conferred on mankind by his life’s work. 261

ISSN:0003-2654    

DOI:10.1039/AN9537800261

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

262 PROCEEDINGS [Vol. 78 PROCEEDINGS OF THE SOCIETY OF PUBLIC ANALYSTS AND OTHER ANALYTICAL CHEMISTS ANNUAL GENERAL MEETING T H E seventy-ninth Annual General Meeting of the Society was held at 2.45 p.m. on Friday, March 6th, 1953, in the meeting room of the Chemical Society, Burlington House, London, W.l. The Chair was taken by the President, Dr. J. R. Nicholls, C.B.E., F.R.I.C. The financial statement for 1952 was presented by the Honorary Treasurer and approved, and the Auditors for 1963 were appointed. The Report of the Council for the year ending March, 1953 (see yp. 264-271), was presented by the Honorary Secretary and adopted. The Scrutineers, Messrs. J. B. Attrill and G. B. Thackray, reported that the following had been elected officers for the coming year- President-D. W.Kent- Jones, B.Sc., Ph.D., F.R.I.C. Past Presidents serving on the Coumil-Lewis Eynon, G. W. Monier-Williams, J. li. Vice-Presidents-A. J. Amos, T. McLachlan and Eric Voelcker. Honorary Treaswer- J. H. Hamence. Honorary Secretary-K. A. Williams. Other Members of Cowzcil-The Scrutineers further reported that 434 valid ballot papers had been received and that votes had been cast in the election of Ordinary Members of Council as follows-A. L. Bacharach, 343; R. C. Chirnside, 334; D. C. Garratt, 334; H. M. N. H. Irving, 257; Miss Mary Corner, 239; H. W. Hodgson, 210; E. G . Whittle, 176; A. L. Williams, 175; Osman Jones, 167; R. H. Morgan, 125. The President declared the following to have been elected Ordinary Members of Council for the ensuing two years-A.L. Bacharach, li. C. Chirnside, D. C. Garratt, H. M. N. H. Irving, Miss Mary Corner and H. W. Hodgson. C. A. Adams, N. L. Allport, B. S. Cooper, N. Heron, H. E. Monk and H. C. S. de Whalley, having been elected members of the Council in 1952, will, by the Society’s Articles of Associa- tion, remain Ordinary Members of the Council for 1953. T. W. Lovett (Chairman of the North of England Section), R. S. Watson (Chairman of the Scottish Section), A. M. Ward (Chairman of the Microchemistry Group), J. Haslam (Chairman of the Physical Methods Group) and H. 0. J. Collier (Chairman of the Biological Methods Group) will be ex-oficio members of the Council for 1953. After the business outlined above had been completed, the meeting was opened to visitors, and the retiring President, Dr.J. K. Nicholls, C.B.E., F.R.I.C., delivered his Presidential Address (see pp. 27 1-280). Nicholls and George Taylor. NEW MEMBERS William John Bayley, B.Sc. (Lond.), A.T.M., F.K.I.C. ; Ronald Blunt, B.Sc. (Lond.) , F.K.I.C. ; Robert Buckley, B.Sc. (Lond.), A.R.I.C. ; Iliilliam Thomas Carter, B.Sc. (Lond.) ; Miss Janet Cartmel, B.Sc. (Birm.) ; Miss Laura Mary Cleverly; Geoffrey Lionel Coulter, B.Sc. (Wales) ; Miss Olive Lucy Drage, B.Sc. (Lond.), A.R.I.C. ; Alfred James Feuell, B.Sc. (Lond.), A.1I.I.C. ; Derek Gutlirie Forbes, B.Sc. (Lond.), A.R.I.C. ; Ronald John Hanson ; Henry Arthur Har- bottle, B.Sc. (Dunelm.) ; Thomas Hewitt, H.E.M., B.Sc. (Lond.), A.R.C.S., A.R.I.C. ; Kenneth John Jarrett, l3.S~. (Lond.), A.1I.I.C. ; Richard Keith Lewis, B.Sc.(Lond.), A.R.I.C. ; Norman Nix, B.Sc. (Notts.), A.R.I.C. ; Donald Albert Pantony, H.Sc. (Lond.), Ph.D. (Leeds), A.R.C.S., A.R.I.C. ; Reginald Jewitt Peace, B.Sc. (Lond.), A.R.I.C. ; Anthony William Charles Phillips, B.Sc. (Lond.) ; John Alexander Pickard; Wynn Price-Davies, B.Sc. (Wales), A.R.I.C. ; Victor William Reid, B.Sc. (Q.U.B.) ; Gordon Edward Simons Richards, A.1I.I.C. ; Derek Wilson Smith; Ronald Alan Jliatkins, K.Sc. (Lond.), A.1I.I.C. ; Robin Albert Woolf, B.Sc. (Lond.). DEATH WE regret to record the death of John Robert Stubbs.May, 19531 PROCEEDINGS 263 PHYSICAL METHODS GROUP T m thirty-ninth Ordinary Meeting of tlie Group was held at 6.30 p.m. on Tuesday, March 3rd, 1053, in the Meeting Room of the Chemical Society, Burlington House, London, W.1.Dr. J. Haslam was in the Chair and about fifty-five members and visitors were present. The following papers on “Absorptiometry” were presented and discussed: “The Use of High Absorbancy Reference Standards in Absorptiometry,” by H. M. Irving, M.A., D.Phil., F.R.I.C. ; “The Determination of Titanium by Precision Absorptiometry,” by W. T. L. Neal, M.A., A.R.I.C., and H. G. Short, M.Sc., A.R.I.C. COMMITTEES, 1953- 1954 THE Council of the Society has appointed the following Cominittees- FINANCE COMMITTEE D. W. Kent-Jones (Chairman), N. L. Allport, Lewis Eynon, J. H. Hamence, H. W. Hodgson, E. €3. Hughes, G. W. Monier-Williams, G. Taylor, A. M. Ward, K. A. Williams (Honorary Secretary). PUBLICATION COMMITTEE J. K. Nicholls (chairman), N. L. Allport, A. J. Amos, A.L. Bacharach, R. C. Chirnside, B. S. Cooper, Lewis Eynon, D. C. Garratt, J. H. Hamence, J. Haslam, H. M. N. H. Irving, G. Roche Lynch, F. L. Okell, G. H. Osborn, J. E. Page, A. A. Smales, G. Taylor, L. S. Theobald, Eric Voelcker, C. Whalley, K. A. Williams, E. C. Wood. POLICY COMMITTEE G. Taylor (Chairman), R. C. Chirnside, J. A. Eggleston, J. H. Hamence, J. Haslam, N. Heron, H. M. N. H. Irving, D. W. Kent-Jones, J. R. Nicholls, A. M. Ward, K. A. Williams. ANALYTICAL METHODS COMMITTEE E. B. Hughes (Chairman), N. L. Allport, R. C. Chirnside, Norman Evers, J. H. Hamence, J. Haslam, D. W. Kent-Jones, R. F. Milton, J. R. Nicholls, F. L. Okell, G. H. Osborn, J. E. Page, R. W. Sutton, G. Taylor, H. C. S. de Whalley, K. A. Williams, D. W. Wilson, E. C. Wood, D. C. Garratt (Honorary Secretary). PUBLIC ANALYSTS AND OFFICIAL AGRICULTURAL ANALYSTS COMMITTEE G. Taylor (Chairman), C. A. Adams, F. W. 17. Arnaud, H. H. Bagnall, W. Gordon Carey, H. Childs, J. F. Clark, S. Dixon, J. H. Hamence, E. S. Hawkins, N. Heron, E. T. Illing, D. W. Kent-Jones, J. King, A. Lees, J. B. McKean, T. McLachlan, C. H. Manley, S. Ernest Melling, G. W. Monier-Williams, H. E. Monk, J. R. Nicholls, C. J. Regan, J. G. Sherratt, R. W. Sutton, R. G. Thin, K. A. Williams, E. C. Wood, Eric Voelcker (Honorary Secretary). STANDARD METHODS OF ANALYSIS COMMITTEE G. Taylor (Chairman), N. L. Allport, D. C. Garratt, J. H. Hamence, D. W. Kent-Jones, J. R. Nicholls, K. A. Williams. LIAISON COMMITTEE G. Taylor (Chairman), J. H. Harnence, K. A. Williams. SOCIETY’S REPRESENTATIVES ON THE JOINT COMMITTEE OF THE SOCIETY AND THE ROYAL INSTITUTE OF CHEMISTRY W. Gordon Carey, S. Dixon, J. H. Hamence, ‘1. McLachlan, J. G. Sherratt, G. Taylor, Eric Voelcker.

ISSN:0003-2654    

DOI:10.1039/AN9537800262

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

264 ANNUAL liEPORT OF THE COUNCIL [Vol. 78 Annual Report of the Council: March, 1953 THE roll of the Society numbers 1592, an increase of 14 over the membership of a year ago. HONOUR-During the year Professor D. N. McArthur has been awarded the C.B.E., and the Council offers him its congratulations. LONG MEMBERSHIP-The congratulations and good wishes of the Council are extended to F. W. F. Arnaud, A. H. Bennett, H. Harman and E. M. Hawkins, who have completed 50 years of membership of the Society, and to S. Elliott, H. Lowe and A. J. Parker, who have completed 40 years of membership. DEATHS-The Council regrets to have to record the deaths of the following members- R. E. L. Davies J. F. H. Gilbard Sir Jack Drummond L. 0. Newton I<. H. Slater F. C. Dyche-Teague A. Rayner F.E. Thompson H. G. Reeves Davies became a Bachelor of Science of Liverpool University with first class honours in 1924 and was elected Associate of the Institute of Chemistry in 1926. He joined the con- sulting practice of A. Norman Tate & Co., in Liverpool, in 1924, and succeeded to it on the death of his father, Joseph Davies, in 1948. He joined the Society in 1949. Drummond was born in 1891 and was educated at King’s College School and East London College, taking his degree in 1913. He was for a short time at the Government Laboratory and then went to the Cancer Hospital Research Institute, where he became Director of Biochemical Research. In 1919 he was Reader in Chemical Physiology at Uni- versity College, London, and was made the first Professor of Biochemistry in the University in 1922.In 1939 he offered his services to the Ministry of Food and in due course became their Scientific Adviser, holding this post until 1946. His work now was to advise on the problems of feeding the people of an island almost isolated by enemy action. To this end it seemed that he ignored to a large extent any question of vitamins, and concentrated on the principle that in the circumstances it was calories that counted. He initiated measures that helped greatly in the effort to prevent any real malnutrition. He was knighted in 1944 and in the same year was elected a Fellow of the Royal Society. In 1946 he became Director of Research to Boots Pure Drug Co., Ltd. He served on the Council of the Society in 1924-5, and on the Council of the Institute of Chemistry.He was an Examiner of the Institute for six years, and Chairman of its London Section. He was a member of the Interdepartmental Committee on Food Standards from 1942, and more recently a member of the Food Standards Committee of the Ministry.of Food. He died tragically, with his family, in France in the summer of 1952 at the hand of an unknown assassin. Dyche-Teague obtained the degree of Bachelor of Science in the University of Birming- ham. He became an Associate of the Institute of Chemistry in 1910 and a Fellow in 1914. He was elected a member of the Society in 1912. At that time he was a consulting analytical chemist and bacteriologist, and he had earlier been with F. E. Parkes and J. W. Gatehouse, Public Analysts. He was a pioneer in the production of British chlorinated rubber and founded Detel Products, Ltd., of which he was managing director.Gilbard died in his 83rd year, 62 years after his election to membership of the Society. He was educated at Vermont College, Clapton, and a t Finsbury Technical College under Meldola and Streatfeild. He became assistant to Bernard Dyer in 1888 and remained with him all his life. He became a Fellow of the Chemical Society in 1895 and of the Institute of Chemistry in 1899. About then he was appointed a Gas Examiner to the London County Council and later to West Ham as well. Newton was educated at Tiffins Boys’ School, Kingston-on-Thames and King’s College, London, and Sir John Cass Technical Institute. He served an apprenticeship with the Locomotive Co.of America and in 1902 became assistant works manager to the Locomotive Co. of Great Britain Ltd. He joined Lassen and Hjort, water purification engineers, in 1907 and became manager of Sofnol Ltd. in 1912, of which company he was managing director from 1921 until his death. He was also retained as consultant to United Water Softeners Ltd. He was a member of the Institution of Chemical Engineers and acted as Honorary Secretary of the Institution for a period of seven years. He was a member of Gray’s Inn. Here his work on the vitamins became famous.May, 19531 ANNUAL REPORT OF THE COUNCIL 265 Rayner obtained an honours degree (B.Sc.) at University College, London, in 1910 and became chemist to Price’s Patent Candle Co. Ltd., Battersea, the following year.He was elected Fellow of the Institute of Chemistry in 1915. In 1926 he set up a consulting practice, mainly concerned with fatty materials, in Manchester, continuing this until his death. He joined the Society in 1937. Reeves was a M.Sc. and Ph.D. of Birmingham University and Doctor of Science of London University. In that year he was Senior Lecturer and Demonstrator in Biochemistry at St. Bartholomews Hospital Medical School, in which department he remained until his death. He was a member of the Physiological Society and the Biochemical Society and an abstractor for Chemical Abstracts in biochemistry. Slater was Doctor of Science and Doctor of Philosophy, University of Edinburgh, and was Grocers’ Company Scholar at the Royal College of Physicians’ Laboratory, Edinburgh, from 1929 to 1932.He worked under Dr. Roche Lynch as Assistant Chemical Pathologist at St. Mary’s Hospital, Paddington, and joined the Society in 1934. He became an Associate of the Institute of Chemistry in 1923 and a Fellow in 1935. At the time of his death he was Principal Biochemist at the Royal South Hants. Hospital, Southampton. Thompson joined the Society in 1906. At that time and until his death he was engaged in private practice in Walsall. At the time when he joined the Society he was Analyst to the Walsall Town Council Sewage Farm Committee. He became a Fellow of the Institute of Chemistry in 1909. ORDINARY MEETINGS-SiX Ordinary Meetings of the Society were held during the year, and the following papers were presented and discussed- He joined the Society in 1928.April, 1052, in London: “ The Determination of Traces of Arsenic in Germanium Dioxide and Tetrachloride.” By S. T. Payne. “ Inorganic Chromatography on Cellulose. The Determination of Thorium by Chromatography on Alumina and Cellulose Adsorbents and the Simultaneous Determination of Thorium and Uranium in Minerals and Ores.” By A. F. Williams, B.Sc., F.R.I.C. “ Inorganic Chromatography on Cellulose. Part X. The Spectrographic Determination of Micro Quantities of Thorium Separated by Chromatography from Minerals and Ores.’’ By G. W. J. Kingsbury and R. B. F. Temple, D.Phi1. Part IX. May, 1952, in London: F.R.I.C. “A Routine Method for the Analysis of Table Jellies.’’ By Miss E. M. Chatt, B.Sc., “The Determination of Oxalates in Fresh Plant Material.” By C.J. L. Baker, A.R.I.C. “ The Determination of Small Quantities of Ammonium Di- or Tri-ethanolamine Alginate in Rayon-Finishing Solutions and on Rayon Yarn.” By E. G. Brown, A.M.C.T., F.R.I.C., and T. J. Hayes. October, 1952, in London: “Spectroscopic Properties of Vitamin A,. Application to the Assay of Cod Liver Oil.” By H. R. Cama, B.A., M.Sc., Ph.D., and Professor R. A. Morton, Ph.D., D.Sc., F.R.S., F.R.I.C. “ The Estimation of Carbonyl Compounds by Semicarbazide and Hydroxylamine with Special Reference to Fatty Acid Oxidation Products.” By A. J. Feuell, B.Sc., A.R.I.C., and J. H. Skellon, M.Sc., Ph.D., F.R.I.C. “ Simultaneous Determination of Pentose and Hexose.” By W. R. Fernell, B.Sc., and H. K. King, M.A., Ph.D., F.R.I.C. November, 1952, in London; meeting organised for the Society by the Biological Methods Group, on the Bio-assay of Vitamins with Special Reference to Microbiological Methods : “ Vitamin Assays-The Relative Roles of Chemical, Biological and Microbiological “Selection of Methods for Routine Assays for Members of the Vitamin B Complex.” “ The Efficient Planning of Microbiological Assays, Particularly Assays of Vitamin B12” Tests.” By L.J. Harris, Sc.D., D.Sc., Ph.D., F.R.I.C. By H. Pritchard, M.Sc., F.R.I.C. By E. C. Wood, B.Sc., Ph.D., A.R.C.S., F.R.I.C.266 ANNUAL REPORT OF THE COUNCIL [Vol. 78 By H. H. Green, O.B.E., DSc. December, 1952, in London: “Industrial Fluorosis.” January, 1953, in Birmingham; meeting organised for the Society by the Physical Methods Group on Chromatography; the meeting was preceded by a tour of the Dunlop Research Centre, Dunlop Rubber Co.Ltd. “Chromatography Past and Present.” By Trevor I. Williams, B.A., B.Sc., D.Phil. “ Inorganic Chromatography on Cellulose. Part XIV. The Quantitative Separation By D. B. Rees-Evans and R. A. of Rhodium, Palladium, Iridium and Platinum.” Wells, B.Sc.. A.R.I.C. “Chrornatograpliy of the Carbohydrates and their Derivatives.” By J. K. N. Jones, Ph.D., D.Sc. ANNUAL GENERAL MEETING-The Annual General Meeting held in March, 1952, was followed by the Second Bernard Dyer Lecture, given by the Hon. Mr. Justice Lloyd-Jacob. The title of the lecture was “Lines of Development.” NORTH OF ENGLAND SECTION-Including the Summer Meeting a t Llandudno, four meet- ings were held during the year at which the following papers were read and discussed- “ Some New Methods in Analytical Chemistry.” By R.Belcher, BSc., F.R.I.C., F.1nst.F. “The Analyst in the Plastics Industry.” By 3. Haslam, DSc., F.R.I.C. “ Synthetic Detergents.” “Chairman’s Address.” By A. A. D. Comrie, B.Sc., F.R.I.C. There are now 455 members of the North of England Section. SCOTTISH sEcTIoN-In addition to the Annual General Meeting, three ordinary meetings were held during the year, one at Edinburgh and two in Glasgow; the following papers being presented and discussed- By C. B. Stuffins, A.R.I.C. “Chemistry and the Law.” By J. K. McLellan, M.A., B.Sc., A.R.I.C. “ Quantitative Microscopy in Relation to Plant Tissue.” ‘‘ Electrophoresis.” By G. T. Mills, B.Sc., Ph.D. A number of members participated in the First International Congress on Analytical Chemistry at Oxford, and a representative attended the summer meeting of the North of England Section at Llandudno.There has been an increase of 4 in the membership of the Section during the year, the total now being 103. MICROCHEMISTRY GROUP-TWO meetings of the Group have been held during 1952. The first, held in London, comprised the Annual General Meeting followed by an Ordinary Meeting of the Parent Society which had been organised by the Group. The Spring Meeting was held in Bristol jointly with the local sections of the Royal Institute of Chemistry, the Chemical Society and the Society of Chemical Industry. The usual Autumn Meeting was not held in view of the International Congress on Analytical Chemistry in Oxford.By Francis Fish, B.Pharm., Ph.C. The following papers have been read- “ Some Applications of the Conway Micro-diffusion Technique.” “ The Microchemical Determination of Iron in Aluminium Alloys.” “ The separation of Carbides from Steel and their Analytical Examination.” by R.- “The Use of Cylinder Oxygen in the Organic Micro Determination of Kitrogen.” By In addition there was an open discussion on “Standard Substances for Organic Micro- analysis” introduced by G. H. Osborn, F.R.I.C., A.M.1nst.M.M. In connection with the 1st International Congress on Analytical Chemistry at Oxford, the Group sponsored certain exhibits of micro-chemical apparatus. A large display arranged by Dr. Stock and Mr. Fill was particularly impressive. This was very favourably commented on by many members of the Congress and attracted considerable attention. Other interesting exhibits were shown by two of the Group’s European members: Dr.Alice Lacourt of Brussels and Dr. M. C. Alvarez Querol of A d a , Spain. Dr. Joy Stern and Messrs. Ingram and Crouch provided other notable exhibits. Hy N. Heron, F.R.I.C. By W. R. Nall. Pemberton. H. Swift and E. S. Morton.May, 19531 ANNUAL REPORT OF THE COUNCIL 267 The Committee has met three times during the year. With the help of a hard-working sub-committee and the co-operation of Group members from many parts of the world and particularly the manufacturers the list of “Standard Sub- stances for Use in Organic Micro-analysis” has now been finalised, and it will be published in The Analyst at an early date.The Committee has given close study to the possibilities of making a film dealing with the use and maintenance of the microchemical balance. Numerous difficulties have been encountered but a synopsis has been prepared and a sub-committee is producing a detailed script. It has been decided that before production is considered this script shall be submitted to the Co-ordinating Film Committee which has been set up to advise on the production of scientific films and which consists of representatives from the Royal Institute of Chemistry, the Scientific Film Association and the British Universities Film Council. Close contact is being maintained with this Co-ordinating Film Committee through the Secretary of the Royal Institute of Chemistry.The questionnaire prepared by the Committee on Microchemical Techniques of the International Union of Pure and Applied Chemistry has been distributed to all Group members to ascertain the extent to which microchemistry is practised. The Committee has given attention to the quality of porcelain microchemical apparatus; and suggestions for the preparation and presentation of papers a t Group meetings. The number of Group members is now 392, an increase of 26 since the last report. PHYSICAL METHODS Gnoup-The Physical Methods Group has held three meetings in London and one in Swansea during the past year. The Swansea meeting was held jointly with the South Wales Section of the Royal Institute of Chemistry. All the meetings were well attended. The Polarographic Discussion Panel, which now has 95 members, organised one of the Group meetings held in London; the Chairman of the Panel is Dr.A. J. Lindsey, and Mr. G. W. C. Milner is Honorary Secretary. The following papers were read and discussed a t meetings of the Group- Annual General Meeting, London, November 27th, 1951. This was followed by an ordinary meeting at which the retiring Chairman, Mr. B. S. Cooper, B.Sc., F.Inst.P., delivered an address on “Light Sources in Chemical Analysis and Testing.’’ Electrographic Analysis Meeting, London, February 19th, 1952. “ Electrographic Analysis-A Brief Survey of its Development with Special Reference “The Identification of Certain Alloys and Stainless Steels by Electrographic Methods.” to Recent British Apparatus.” By G.C. Clark, A.R.I.C., and E. E. Hale, A.R.I.C. By P. R. Monk, B.Sc., A.R.C.S., A.R.I.C. Polarography Meeting, London, April 8th, 1952. “The Measurement of Diffusion Current with Special Reference to the Tinsley Pen- “ Hypochlorites and the Dropping Mercury Electrode.” By E. N. Jenkins, M.Sc., “ The Polarographic Determination of Tellurium in Selenium. ” By G. H. Osborn, recording Polarograph.” By W. Furness, B.Sc., F.R.I.C. A.R.I.C. F.R.I.C., A.M.Inst.M.M., and J. G. C. Cobb. Ion Exchange Resins Meeting, Swansea, May 16th, 1952. “The Theory of Ion Exchange.” “Some Newer Applications and Techniques of Cation and Anion Exchange Resins in “ The Determination of Individual Rare Earths by Radio-activation using Ion Exchange The meeting of the Society held in Birmingham on January 30th, 1953, was organised by The number of Group members is now 418.This represents an increase of 30 since the BIOLOGICAL METHODS GROUP-The Group has held three meetings during the year and By Professor C. W. Davies, D.Sc., F.R.I.C. Chemical Analysis.” Separation.” By G. H. Osborn, F.R.I.C., A.M.1nst.M.M. By F. W. Cornish, BSc., Ph.D., A.R.I.C. the Group. last Annual Report. has also arranged a meeting on behalf of the Society.268 ANNUAL REPORT OF THE COUNCIL [Vol. 78 The Annual General Meeting on December 13th, 1951, was followed by an Ordinary Meeting at which the following papers were presented- “A Critique of in vitm Estimation of Therapeutic Index (Toxicity Index).” By S. “Units of Biological Activity.” On March 14th, 1952, the subject under discussion was the Assay of Coagulants and Anticoagulants. Rosemary Biggs, M.D., M.B., B.S., M.R.C.S., L.R.C.P., read a paper on “The Measurement of Prothrombin in the Control of Anticoagulant Therapy with Tromexan” and was followed by V.J. Birkinshaw, Ph.C., and K. L. Smith, M.P.S., who discussed “The Assay of Heparin, Protamine and Russell Viper Venom.” The Summer Meeting took the form of a visit to the premises of Boots Pure Drug Co. Ltd., Nottingham. On June 12th, 1952, visits were made to the Pharmacology, Bacteriology and Bio-Assay Divisions at West Bridgford, where a most interesting and comprehensive collection of laboratory demonstrations had been arranged by the staff of Messrs. Boots. In the evening, members, together with their wives and friends, met socially at an informal dinner.Next morning the party visited the Beeston factory and after lunch saw further laboratory demonstrations at the Veterinary Science Division, Thurgarton, where the follow- ing papers were presented- Morris, D.Sc., and A. Jones, By N. T. Gridgeman, B.Sc., F.R.I.C. “The Assay of Adrenaline Cream.” By G. F. Somers, B.Sc., Ph.D., Ph.C. “The Assay of Pertussis Vaccines for Antigenicity and Toxicity.” By P. W. Muggleton, The meeting was both instructive and enjoyable and it is hoped it will be possible to hold a similar meeting annually. A meeting of the Society was organised by the Biological Methods Group on November 5th, 1952, the subject under discussion being “The Bio-assay of Vitamins, with Particular Reference to Microbiological Methods.” Twenty-one new members have joined the Group during the year and there have been six resignations.The total membership now stands at 212. ANALYTICAL METHODS COMMITTEE-Although the work of the Sub-committees during the year has not produced many Reports for publication, nevertheless considerable activity has been in progress. Publication of “The Determination of Carotene in Green-leaf Material. Part 11. Green-leaf Materials other than Grass” (ArtaZyst, 1952, 77, 171) completed the work of the Panel appointed to investigate this subject. A Panel formed by the Meat Extracts Sub-committee reviewed the methods of determina- tion of meat with respect to the Meat Products Order, 1952, and published recommended methods of analysis (Analyst, 1952, 77, 543). The Sub-committee has also published its “Second Interim Report on the Determination of Gelatin in Meat Extracts and Meat Stock” (AnaZyst, 1953, 78, 134).It was hoped that a standard procedure for lead in foodstuffs would be available but although considerable experimental work has been undertaken, the Metallic Impurities in Foodstuffs Sub-committee must reluctantly defer their findings as the high reagent blanks make the present procedure unreliable when small fractional parts of lead are present. Work on a different approach to the problem is proceeding. The Essential Oil Sub-committee is nearing completion of its work on the determination of linalol. A Sub-committee has been appointed on Methods of Analysis of Ice Cream under the Chairmanship of Dr. Hamence (AnaZyst, 1952,77,334) and has already done considerable work.met three times during the past year. The Joint Negotiating Committee has agreed upon recommendations for salaries and conditions of service for whole-time Public Analysts to operate as from July lst, 1952. The recommendations are based on principles similar to, though not in all respects the same as, the recommendations of the Joint Negotiating Committee for Chief Officers of Local Authori- ties, for salaries and conditions of service for Chief Officers occupying posts for which salaries exceed E l ,000 per annum. The Committee recommended that a letter be sent to the Ministry of Food recording their regret at the withdrawal of the advisory service in connection with questions arising from BSc., Ph.D. PUBLIC ANALYSTS AND OFFICIAL AGRICULTURAL ANALYSTS COMMITTEE-The COInmitteeMay, 19531 ANNUAL REPORT OF THE COUNCIL 269 the enforcement of the Defence (Sale of Food) Regulations and orders made thereunder, and asking that the service be reinstated. A sub-committee consisting of Messrs.Hamence, Monk and Regan has been appointed to consider matters relating to the Fertilisers and Feeding Stuffs Act, 1926. They have already made some investigational work for the Ministry of Agriculture in connection with methods of analysis. The Ministry of Housing and Local Government have agreed to consider a review of fees, and the list of designated analysts in matters relating to the Rag Flock and other Filling Material Act, 1951. LIAISON COMMITTEE-DLKrhg the year the following appointments have been made- Dr.J. T. Stock, Microchemical Apparatus Committee. Mr. B. J. Walby, Laboratory Apparatus Drawing Conventions Committee. Mr. D. W. Wilson, Silica Gel Committee. Dr. J. G. A. Griffiths has been re-appointed as the Society’s representative on the Joint Library Committee of the Chemical Society for 1953. The Council of the Society takes this opportunity of thanking all its representatives for the work they have carried out on the various Committees during the year on behalf of the Society. HONORARY TREASURER’S REPORT-In the report for 1951 reference was made to the Society’s increasing expenses, particularly the cost of publishing The Analyst, and “but for a timely grant from the Chemical Council at the end of the year we might have finished with an adverse balance.” The position of the Society’s finances a t the end of 1952 is similar to that for 1951 and again we are indebted to the Chemical Council for a grant towards the cost of The Analyst, the sum being considerably more than any previous grant.Our thanks are due to the Chemical Council for their help, but it is only right that members should realise that without aid from the Chemical Council the subscription rate to the Society would inevitably have to be raised. The increased expenditure this year is again mainly due to additional costs in the production of The AnaZyst both from the point of view of editorial staff and printing costs. It is, however, gratifying to report once again increased sales of The AnaZyst for 1952. During the year under review an experiment has been made with a view to obtaining increased income from advertisements in The AnaZyst.For some months now the advertisements in The AnaZyst have been printed on a better quality paper that has resulted in far clearer reproductions, which we hope will render The AnaZyst a greater attraction to potential advertisers. At the same time the charge for the advertisements has been increased; although the effect of this increase will not be fully appreciated until 1953, the balance sheet for 1952 shows an improvement in respect of the income from advertisements. This includes 480 pages of the Proceedings of the First International Congress on Analytical Chemistry, held at Oxford, September 4th to 9th, 1952, containing 43 papers and 3 lectures.Contributed papers and notes amounted to 83 and 28, respectively, which gives a total of 129 papers (and lectures) and 28 notes; against 103 papers and 47 notes during 1951. The approximate number of pages occupied by papers and notes in 1952 was 970 com- pared with 670 in 1951. Six issues of the Bulletin have been distributed with The Analyst. The printing number of the monthly issues is now 4800. BRITISH ABSTRACTS-The cost of preparing British Abstracts has risen enormously in the last year or so, and the Bureau has made determined attempts to find some means of keeping their production an economic possibility. For this purpose an approach was made to the American Chemical Society with a view to amalgamating the production of abstracts on the two sides of the Atlantic.Unfortunately this came to nothing through no fault of the British negotiators. In October, 1952, the Chairman of thc Bureau informed the Society that it would not be possible to continue British Abstracts on their present basis, and power was taken to wind the Bureau up. At the same time an approach was made to Her Majesty’s Government for assistance. The Lord President of the Council referred this appeal to the Royal Society, and that body set up a Committee to consider the matter and advise the Government. The Bureau is completing its task of producing abstracts for the year 1952, B.S. I. Committees- THE ANALYST-The 1952 volume contained the record number of 1032 pages.270 ANNUAL REPORT OF THE COUNCIL [Vol. 78 and it is understood that an interim grant of L5,OOO has been made by the Government to enable it to carry on with a limited programme.The future of the production of abstracts in general is therefore a t the moment uncertain but the portion of British abstracts most likely to survive is Abstracts C, which has always been most nearly self-supporting, and which the Society has supported for the last three years. The belief that abstracts of original papers dealing with Analytical Chemistry would survive has led the Council of the Society to await developments before taking positive action in the interests of members and sub- scribers to The Analyst. CHEMICAL CoUNcIL-During the year the Chemical Council has again distributed large sums of money, subscribed by Industry, to assist in the production of original papers and abstracts, and the Council acknowledges with thanks a grant for the year of fT1400 towards the cost of producing l h e Analyst.DEVELOPMENT OF THE socIETY-The Council referred the question of the future develop- ment of the Society to its Policy Committee for consideration early in the year, and it has adopted the following recommendations made by the Committee: (1) that the Society should institute a Junior Grade of Membership for young members at a reduced subscription; (2) that Ordinary Meetings of the Society should be arranged outside London once or more times each year; (3) that each Group of the Society should be invited to sponsor one meeting of the Society each year; (4) that the Publication Committee of the Council should be respon- sible for deciding on the subjects of the Ordinary Meetings of the Society.(5) It was hoped that the Chairmen and Honorary Secretaries of the Sections and Groups might meet the Officers of the Society once a year to exchange information and assist in the development of the Society. NAME OF THE socIETY-During the last year or so a suggestion has come to the fore of the formation of a professional association of Public Analysts, and it has received a very considerable body of support. It may, indeed, be stated that the formation of this body is under way. It is expected that the new body will wish to discharge the functions that the Society has for so long undertaken on behalf of Public Analysts, and that, in consequence, there will no longer be any necessity for the Society to retain in its Memorandum and Articles of Association the “professional” clauses.Should the members of the Society agree to their deletion, it will be possible for the Society to take its place-in the Council’s opinion, its rightful place-among the Learned Societies. It is the intention of Council to invite members to agree to changing the name of the Society as was proposed some years ago to “The Society for Analytical Chemistry.” At the same time, and to mark the prominent place that Public Analysts have taken in the growth of the Society during the long course of its history, the Council desires members to agree to placing a sum of money from the Society’s reserves at the disposal of the new Professional Association of Public Analysts to assist its formation and development.INTERNATIONAL CONGRESS ON ANALYTICAL CHEMISTRY-The International Congress in which the Society has been taking an interest ever since the idea was first mooted, duly took place in Oxford in September, 1952, under the Presidency of Sir Robert Robinson, and with Sir Wallace Akers as Honorary Treasurer and Mr. R. C. Chirnside as Honorary Secretary. The Chairman of the Executive Committee was Mr. George Taylcr, Past President. The Congress attracted about 700 members from 26 different countries. Three Congress Lectures were given by Dr. Ralph Muller, Dr. L. H. Lampitt and Professor C. J. van Nieuwenburg, and there was a further special paper by Professor I. M. Kolthoff. Papers were grouped by subjects in 9 sections. Simultaneously demonstrations of laboratory technique were held in the Dyson Perrins Laboratory and provided a display of the greatest interest.A trade exhibition of 44 stands was held during the Congress. A banquet was held in Christ Church, there were receptions by Sir Robert Robinson and the Mayor of Oxford, a garden party in the grounds of Wadham College, and excursions to places of interest. Arrangements were made by the editorial staff of the Society for the pre-printing of the papers presented to the Congress, and these, together with the discussion on the papers, were printed in the November and December issues of The Analyst, where they occupied nearly 500 pages. It is believed that the speed with which the report thus appeared is a record in scientific circles. DYER MEMORIAL MEDAL-Following a decision of Council taken some time ago, Mr. T. H. Yaget was invited to design a medal for presentation to those who give Bernard Dyer Memorial The proceedings of the Congress have since appeared in book form.May, 19531 ADDRESS OF THE RETIRING PRESIDENT 27 1 Lectures to the Society. Mr. Paget is very well known as a medallist, having been responsible for the obverse of coins of the last reign, and having designed, among other medals, the Castner Medal of the Society of Chemical Industry. His design was accepted by the Council of the Society, and the Dyer Memorial Medal was made from it by the Royal Mint. Copies of the medal were presented to the first two Bernard Dyer Lecturers, Sir E. John Russell and the Hon. Mr. Justice Lloyd-Jacob, at the Biennial Dinner held on March 6th, 1953. sented the Council on this Committee during the year. BRITISH JOINT COMMITTEE ON ANALYTICAL DEFINITIONS-Mr. C. J. Regan has repre- CHEMISTS’ CONFERENCE OF THE METHODS OF ANALYSIS COMMITTEE (METALLURGY, GENERAL DIVISION) OF THE BRITISH IRON AND STEEL RESEARCH ASSOCIATION-Mr. R. C. Chirnside and Dr. J. Haslam represented the Council at this Conference. J. R. NICHOLLS, President. K. A. WILLIAMS, Honorary Secretary.

ISSN:0003-2654    

DOI:10.1039/AN9537800264

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

May, 19531 ADDRESS OF THE RETIRING PRESIDENT 27 1 Address of the Retiring President J. R. NICHOLLS, C.B.E., DSc., F.R.I.C. (Delivered after the AnnztaL General Meeting, March 6th, 1953) BEFORE I address you on the subject I have chosen, I propose, in accordance with precedent, to review briefly some aspects of the activities of our Society. This can indeed be brief, since the Annual Reports of the Council for this year and last give a complete rksum6 of the Ordinary, Sectional and Group Meetings. This record speaks for itself; but it is important to note that Council has started the policy of holding ordinary monthly meetings outside London and these are to be arranged by an appropriate Section or Group. Our membership continues to grow steadily, and although the rate of increase appears to have temporarily slowed down, it is interesting to note that our present number is 60 per cent.greater than 10 years ago, when we just reached the 1000 mark. Increase in numbers is a balance between new members on the one hand and deaths and resignations on the other. It is inevitable that time should take toll among the older members of a society; but the tragic deaths of Dr. Cox and Sir Jack Drummond are exceptional. The Analyst has maintained its high standard and the last volume was a record in size owing to the inclusion of the Proceedings of the First International Congress on Analytical Chemistry held at Oxford last September. The Society has received many congratulations on the speed with which the Proceedings were published, and credit for this must go largely to Mr.Chirnside, Honorary Secretary of the Congress, and to the editorial staff of this Society. I do not propose to make extended reference to the various Committees of the Society; but I should like to emphasise how fortunate we are in having so many people who give so much of their time voluntarily to the work of the Society. It is perhaps not out of place to refer again to the sending of three Society delegates to the XIIth International Congress of Pure and Applied Chemistry in New York. The congratulatory address presented to the American Chemical Society on the occasion of the celebration of its 75th anniversary was suitably acknowledged by the President of that society. The second Bernard Dyer Memorial Lecture was given last March by the Honourable Mr.Justice Lloyd- Jacob. In the Annual Report of Council (see pp. 264-271) there is an item under the heading “Name of the Society.” This records developments that have been and are taking place and which may lead to the Council proposing a change in the name of the Society. The back- ground to these developments was dealt with very fully by my predecessor, Mr. George Taylor, two years ago in his Presidential Address (AnaZyyst, 1951, 76, 260), and I would recommend you to read this again when the Council’s proposals come before you. During his term of office a president sees much behind the scenes, and it is only then that he appreciates who is really responsible for the smooth running of what appears to be almost a machine. I should, therefore, like to pay tribute to the strenuous and devoted work of our Honorary Secretary, Dr.K. A. Williams, and our Honorary Treasurer, Dr. J. H. Hamence. The stimulating subject was “Lines of Development.” With them I must associate the whole of the Editorial and Office staff.272 ADDRESS OF THE RETIRING PRESIDENT [Vol. 78 PUBLIC HEALTH HAZARDS AND THE ANALYTICAL CHEMIST During the present century there have been significant changes in the work of the analytical chemist. One of the most important of these has been the increasing emphasis placed upon the determination of small quantities of substances. There are two aspects of this. In one, major constituents are determined on small quantities of material, and the techniques of microchemistry have been worked out to such a degree of fineness and precision that micro-methods are direct competitors with macro-methods. In the other, minor con- stituents are determined at various concentrations down to the infinitesimal.These minor constituents may be integral parts of the material dealt with and may be responsible for part of its particular properties or virtues. On the other hand they may be adventitious, 2.e. , non-essential additions or materials accidentally picked up. Some of these may introduce a health hazard, and it is because of this that the determination of the amounts present has become of primary importance. Any legislative control to minimise such hazards must be founded on medical and pharma- cological advice; but it is the chemist who will be called upon for evidence to enforce such control, and his general knowledge on the one hand of the materials likely to affect human beings, and on the other of the needs of industry, enables him to advise on the reasonableness or otherwise of any measures proposed.Hence the members of this Society, whether public analysts or other analytical chemists, must play a prominent and even leading part in all public health matters. The risks from small quantities of particular substances comprise only part of public health hazards. Of recent years a problem has arisen, generally known as chemicals in food, and the adequacy of existing legislation as a protection against possible hazards from substances used in relatively substantial amounts has been questioned. In this country there have been several meetings at which the subject has been discussed and different points of view of the various interests have been ventilated.But the public may be affected by chemicals in other commodities besides food, and in 1949 the Advisory Council on Scientific Policy was asked to examine the existing departmental arrangements for controlling the use of potentially toxic substances or processes in the preparation of various kinds of consumer products. An Expert Committee on Toxic Substances in Consumer Goods was appointed under Professor Zuckerman, and the recommendations of this Committee were considered by the Advisory Council, together with the views of the Medical Research Council and of the Government departments concerned. The conclusions are given in the Fourth Annual Report of the Advisory Council (1950-51, H.M.Stationery Office, Cmd. 8299) and may be briefly summarised as follows- The risk to life and health owing to the presence of toxic substances in consumer goods is probably small, but the rapid growth of the chemical industry and the needs of industry in general are accelerating the pace at which new chemical substances are being introduced into consumer products, and the machinery that exists for testing the possible harmful effects of these substances is inadequate. Government departments should acquire information about possibly noxious substances or processes that industry may contemplate using before they are allowed to find their way into the composition or treatment of the articles concerned.New legislation need not be introduced a t present. Manufacturers should be informed that they are expected to take all reasonable care to ensure that no new substances should be offered for sale for use in consumer goods if toxic effects are suspected. A standing committee should be set up in order that there may be a central organisa- tion to which Government departments can turn for advice. The Medical Research Council should keep the whole problem of toxic substances under review and should initiate research. Information over the whole field of toxic substances should be interchanged with appropriate authorities in other countries, particularly in the United States. This policy is likely to be generally approved, but there may be differences of opinion as to how it should be implemented.Several Government departments may be concerned in obtaining the information about noxious substances and there may be a tendency to deal with certain aspects of the problem piecemeal, action being taken against a particular hazard that seems of immediate importance. This is unlikely to be satisfactory, as reasonableMay, 19531 ADDRESS OF THE RETIRING PRESIDENT 273 protection should be envisaged and applied before a possible danger shows signs of becoming an acute reality. The measures proposed to minimise one risk must be equally applicable to many others and all should be considered together. I should like to put before you my views on how the policy should be implemented, and as there are a few risks that may arise from sources other than consumer goods, I propose briefly to survey the whole field of public health hazards before indicating how the general problem might be tackled, as far as possible within the framework of existing legislation. I shall not consider industrial hazards, as these are more appropriate for particular treatment and, in themselves, are essentially medical questions. SURVEY OF PUBLIC HEALTH HAZARDS Public health hazards may arise from- (1) Air; (2) Water; (3) Food; (4) Clothing ; ( 5 ) Cosmetics; (6) Household materials. (1) AIR HAZARDS- Human beings are continually exhaling carbon dioxide, and the amount in the air is augmented by the burning of all types of fuel.In view of the vast extent of the atmosphere and the capacity of vegetation to utilise carbon dioxide for photosynthesis, the normal hazard from this gas is negligible. There are, however, other polluting substances that arise from the combustion of fuel, including unburned and partially burned coal dust, ash dust and grit, coke particles, tarry soot and gaseous sulphur dioxide.Much of this is fine particulate matter conducive to the production of fog, and during this last winter there were periods when fog prevailed for some days, and excessive and unexplained fatalities occurred to human beings and animals. Some medical authorities were of the opinion that local and unusual concentrations of carbon dioxide and other contaminants could not be excluded as a possible cause, even if only contributory. Whether or not this is correct, it is possible that traffic congestion in busy streets may produce a hazard over and above those mentioned, as the exhaust gases from car engines include, in addition, carbon monoxide and the products of pyrolysis of oils with their increasingly varied additives. The exhaust fumes from factories contribute in a similar way; and while national and local authorities take appropriate measures if there is a nuisance, the aspect should not be overlooked that there may be a public health hazard. Particulate matter in the atmosphere, not sufficient to cause a nuisance, may settle as dust and subsequently be blown about to be inhaled.These particles, no doubt, remain in the lungs after breathing. (2) WATER HAZARDS- Water authorities are very conscious of their responsibility to supply a pure article. They make sure that no contamination occurs in their plant or filter beds. But the water comes from a large catchment area and there is always the possibility of contamination either of the natural sources or from polluted areas. We know that certain waters contain high proportions of fluorine; and although the effect of this has been described as only a cosmetic blemish, there are pathological effects if the amount of fluorine is too high.The complete absence from very pure water of certain trace elements, such as iodine and fluorine, may raise the question of deficiencies, for which counter measures may be necessary. This is so closely connected with public health hazards that it must be considered with it. The general problem of water pollution is a wide one and goes far beyond my present survey.But there are many ways in which the public health may be involved and this aspect must not be lost sight of. Special problems may be created by the more widespread occurrence of radioactive elements. (3) FOOD HAZARDS- divided into a number of general classes. As already mentioned, food is a potential source of many hazards and these may be274 ADDRESS OF THE RETIRING PRESIDENT [Vol. 78 (a) Metallic contamination-The possible dangers from poisonous metals are well known and good commercial practice tends to reduce the amounts present to negligible proportions. One has to consider not only the quantity present in a particular food but also that which may be present in the complete diet, as absorption of some metals is cumulative. For this reason it is desirable that steps should be taken to reduce the quantity of a poisonous metal present in any one food to the lowest commercially practicable amount.With very poisonous metals, such as arsenic and lead, ordinary commercial practice may not be the best possible to eliminate risks of contamination, and the ideal should be that of the most up-to-date and well-equipped producer. There is a consensus of opinion that the plant used in preparing food for sale should not yield harmful metals to food. Lead pipes should not be used for conveying liquids such as beer and cider. This has been recognised by the trade and it is largely the difficulty of obtaining replacements during recent years that has prevented their abandonment.It can be hoped that this hazard will be removed within a reasonablyshort time. Reputable manu- facturers are aware of the possible danger, but it is doubtful if our present legislation is ade- quate for the necessary control. (b) Bacterial coiztamination-For manufactured foods this is essentially a matter of hygiene, and good commercial practice results in a negligible risk. Some foods eaten raw, such as salad crops, may be grown on land treated with fertilisers or compost made from sewage sludge and this may entail a risk. (c) Extraneous matter-Foods are subject to contamination by rodent residues, insects and mould a t all stages of their history. This contamination is minimised by proper hygiene and good commercial practice; but as such matter is largely avoidable, some control may be necessary. (d) Wrapping materials-Pre-packed food comes in contact with a variety of packing materials, and these should not contribute harmful substances to food. Suitable metal foils and plastic materials are known and recommended; but it must be remembered that not all plasticisers and breakdown products of plastics are harmless.(e) Insecticidal residues-This is a very difficult problem, whether considered from the point of view of the chemist or from that of public health. I t may be essential to use insecticides to obtain the maximum supply of natural foods, and it may be inevitable that traces remain in the food that reaches the public. Very potent insecticides have recently been developed and it may be economically essential to use them rather than less dangerous ones, This may be an instance where we are obliged to take a risk; but we ought to know how much remains in the food, what is the fate of the excess used and the nature of any decom- position products.A balance will have to be drawn between economic necessity and possible dangers. If it is essential to accept a risk, the extent of that risk should be known with some degree of exactitude. (f) Chemicals in food-Here I shall deal with chemicals that are deliberately added for what may be called technical reasons, and I am using the term “chemical” in its widest sense. First, I should emphasise that improvements in food technology should be encouraged in every way, as they help to make the best use of the world’s inadequate food supplies.Many alarmist statements have been made about the addition of chemicals to food, and most of these are generalisations from particular and exceptional examples. Hence they must be severely discounted, but they cannot be ignored. All reasonable people agree that the addition of either natural or synthetic chemicals to food may involve a risk to the consumer if there is inadequate knowledge of the pharmacological action of the chemical. Synthetic chemicals as a class cannot be regarded as potentially more toxic than natural ones, for some of the most dangerous poisons are isolated from natural material. It would be completely unreasonable to forbid the use of all chemicals in food manufacture; each must be considered on the information available. But I would suggest as a general guide that if a chemical has little or no food value, it should not be added to food if there is any doubt of its harm- lessness and only then if there is justification for its use.Now it is very difficult, if not impossible, to prove that a substance is completely harmless. What can, however, be done, is for pharmacologists to lay down what tests should be carried out to obtain inform a t’ ion upon which an opinion can be based. As knowledge increases, the criteria and tests may need to be revised. This increase in knowledge may have to be sought deliberately by planned research as recommended by the Zuckerman Committee. An important point will be upon Cooking utensils for household use should not contaminate food.May, 19531 ADDRESS OF THE RETIRING PRESIDENT 275 whom shall lie the responsibility for carrying out the tests laid down; this I shall come to later, when I make suggestions as to control.Assuming that tests are prescribed and the responsibility for carrying them out has been localised, I foresee no practical difficulty with such substances as anti-oxidants, emulsifying agents, anti-staling agents and preservatives, as they are relatively pure substances of simple constitution and their numbers are not likely to be great. The position is not so simple if there are many substances of a class, any one of which may be used, and particularly when the members are of widely varying and complicated chemical structure. What I have in mind is food colours, and I must spend a little time in discussing them.These are used legitimately for improving the appearance or attractiveness of foods and, as they are used in quite small proportions, it may be suggested that the risk from them is negligible. This is not so, as we are all aware that certain colours are dangerous and some are already prohibited for use in food. The prohibition of these colours was made over 25 years ago and it cannot be accepted that these are the only ones that are harmful. Synthetic colours are usually made by coupling intermediates that in some instances are known to be toxic. Some of these intermediates are closely allied in constitution to substances that have been proved to be carcinogenetic and we do not know if they are re-formed in the body by breakdown of the colour. What happens to the characteristic linkage of the azo dyes during their passage through the body? How much of the colour is broken down and what are the resulting products? These are all questions that ought to be answered at some time.Meanwhile, no colour should be used in food if there are serious doubts as to its harmlessness. Manufacturers would still have a wide choice of colours that are not suspect in our present state of knowledge; and many additional shades can be produced by appropriate blending. The special action that may be necessary for controlling colours used in foods will be dealt with later. A new development of recent times concerning the presence of chemicals in food is the specialised use of certain drugs in the breeding of poultry and animals for human food.Stilboestrol is used for the tenderization of poultry flesh and this involves the slow absorption of the drug by the birds over a long period. The unabsorbed drug is removed when the head and neck are cut off before the bird is sold to the consumer; and although the practice may result in the production of more marketable birds, what of the affect, if any, on the consumer of the meat? The action appears to be rather the prevention of a depression of growth by specific action on the gut flora, and there may be a risk of the appearance of resistant strains, so that more and more of the antibiotic is required, with subsidiary effects not now apparent. Apart from the probably small risk to the public of normal use in this way, there is clearly a possible danger in placing powerful drugs in the hands of poultry breeders and stockfeeders. (4) CLOTHIXG HAZARDS- The risks from clothing are few, but the effects of dyes, particularly in furs, must be considered.Furs are also sold permanently moth-proofed, and this involves the retention of chemicals that may be in contact with warm skin for several hours. Special detergents are sold for washing undergarments, and a property that makes a good advertising point is that no rinsing is required. The washed article, therefore, contains small but significant amounts of substances that remain in contact with the skin for many hours, with the possibility of absorption. Optical bleaching agents for white garments depend for their value upon substances remaining in or on the article treated, and which remain after washing.Although some of these substances are claimed to show their effect after repeated washings, and therefore must be very insoluble, there is no guarantee that absorption does not take place when in contnct with the skin and perspiration. Crease-resisting agents are incorporated in some fabrics. These are likely to be made up into external garments; but the material may be in contact with the skin. Is the body capable of removing sulphonic acid groupings? Antibiotics are used for increasing the rate of growth of pigs. (5) COSMETIC HAZARDS- This country has no special legal control over the ingredients of cosmetics, and it does not seem sufficient protection to the public that anything can be sold for application to the external surface of the human body without consideration being given to the possible harmful effects. M'lde we can assume that no manufacturer would include in his preparations a substance known to be harmful, can we be certain that all the substances used are, in fact,276 ADDRESS OF THE RETIRING PRESIDENT [Vol.78 harmless? If there is a hazard, it is likely to affect nearly half of the population of most countries. What of the purity of the dyes and colours used? These are applied regularly, in some instances in considerable amounts, and consideration must be given to their effects. (6) HOUSEHOLD HAZARDS- A variety of substances are now being sold as household detergents. They are very suitable for the purpose, but one of their characteristics is a tenacious adherence as a surface film on the article cleaned.The amount remaining after wiping may be minute, but there must be an accumulation on the drying cloth used and this may mean that no household plate, dish or glass is completely free from these powerful surface-acting agents, and significant amounts might remain on the crockery of catering establishments. Many of these detergents contain in addition a foaming agent, which contributes to the efficiency of the cleansing action. These foaming agents pass into sewers and rivers, and if there is a sufficient accumulation, patches of foam may collect and remain for days. While this is normally only a nuisance, there may be instances where water is drawn from a river for subsequent household use and filter beds may be incapable of removing the foaming agents.To remove the effect of the foaming agents in efAuents other chemicals have been proposed, and the addition of these may bring other problems. Detergents and foaming agents are also used in sliampoos and here an incidental and unsuspected hazard has recently arisen. When hair is shampooed the liquid may run into the eyes, and irritation and slight damage has been caused by certain preparations. There are some minor household hazards, such as the risk of children sucking toys coloured with soluble paint, which need not be dealt with except to say that it might be desirable if powers existed for their general control. They are so efficient that little rinsing appears necessary. CONTROL OF PUBLIC HEALTH HAZARDS Having considered the whole field of public health hazards somewhat comprehensively, but certainly not exhaustively, I should like to give my views of the sort of control I think necessary, bearing in mind the policy outlined by the Advisory Council.On principle the people of this country do not look kindly on controls, and this is a worthy attribute that should be encouraged. On the other hand, there is little antipathy to controls that are proved necessary. Everyone is agreed that where people cannot protect themselves some controls are necessary, and rarely is a voice raised against any reasonable measure to ensure public health. The various hazards to which I have referred can be broadly divided into three classes, vz2.- (1) Hazards due to lack of hygiene; (2) Hazards due to contamination; (3) Hazards due to “chemicals,” using that term in the widest sense.These are preventable or largely minimised by proper hygiene and are almost negligible with good commercial practice. In the household, control is the concern of the housewife, and education and common sense are sufficient safeguards. As regards food for sale to the public, we have already legislation to cover the cleanliness of food, and Government depart- ments and local authorities have power to make any regulations in respect of places where food is prepared. Reputable manufacturers are little concerned with such control, as their domestic standards are generally higher than any officially prescribed minima. (1) HAZARDS DUE TO THE LACK OF HYGIENE- (2) HAZARDS DUE TO CONTAMINATION- These arise from traces of material unavoidably present even with good commercial practice, such as metallic contamination, or from substances remaining as traces after legitimate use for other purposes, such as insecticidal residues, or from substances permitted to be added in particular instances, such as preservatives.For these, statutory tolerances are appropriate, and as regards food, powers exist under Public Health or Food Acts to prescribe such limits. Similar powers would be appropriate for cosmetics and any other consumer goods liable to the hazard. The Atmospheric Pollution Research CommitteeMay, 19531 ADDRESS OF THE RETIRING PRESIDENT 277 concerns itself with obtaining data on air contamination, but possibly rather more on the side of the prevention of nuisances than that of hazards; these two aspects clearly overlap, At the present time the Food Standards Committee of the Ministry of Food has a Sub- committee dealing with Metallic Contamination of Food and several reports have been published with suggested tolerances (copper, M.of F. Bulletin No. 611, 1951 ; arsenic, M. of F. Bulletin No. 616, 1951; lead, M. of F. Bulletin No. 628, 1951; tin, M. of F. Bulletin No. 685, 1953). The Minister of Agriculture and Fisheries appointed a Working Party on Precautionary Measures against Toxic Chemicals used in Agriculture and its first report was published in 1951 (H.M. Stationery Office, Code No. 26190). This Working Party was subsequently asked by the Ministers concerned (Joint Announcement by the Ministry of Agriculture and Fisheries, the Ministry of Health, the Ministry of Food and the Department of Health for Scotland, June, 1951) to enquire whether any risks arise, from the point of view of the consumer of the final product, in the use of toxic chemicals in agriculture and in the storage of food, and to make recommendations for protective measures should these appear to be desirable.I t is in connection with hazards due to contamination that our Society can play a most important and essential part. Any tolerances allowed must be capable of being enforced, and it is the chemist who must develop the methods for determining all the contaminants and he is likely to be more and more called upon in connection with insecticidal residues and the like. No report has yet been issued.(3) HAZARDS DUE TO CHEMICALS- These arise where the harmlessness of the chemical has not been proved, and here statutory tolerances are, in general, inappropriate ; either the chemical should be permitted or its use should be forbidden. At present, powers exist for forbidding by regulation the use of a substance in food if it is known to be harmful. But the position as regards other consumer goods is not so clear. In general, all sales are subject to the Sale of Goods Act, which requires any article sold to be reasonably fit for its normal purpose. The emphasis here is on fitness for use rather than the possibility of a hazard; even where there is a risk, the idiosyncracy of certain individuals may be raised as a defence. Other Acts, e.g., the Factories Act and the Petroleum Acts, have some bearing on public health, but they are really more concerned with particular dangers and with nuisances. The Public Health Acts and the Food and Drugs Act have already been referred to, and Government departments and local authorities have powers to make regulations and bye-laws under various Acts.Whatever control measures are envisaged, it seems generally agreed that provision must be made for periodical review. This can be achieved only by a permanent body such as was recommended by the Zuckerman Committee and approved by the Advisory Council. The Pharmacy and Poisons Act, 1933, established a Poisons Board, and we now have twenty years’ experience of its working. The Board meets periodically and considers what control is necessary over the sale of poisons to the public.The Board’s recommendations are reported to the Home Secretary, who considers them and, if he thinks fit, makes Regulations that are laid before Parliament and to which objection can be raised. If necessary, control action can be taken very rapidly, and can equally quickly be amended. I do not think that any objection has been raised to any action that has been taken as a result of the recommendations of the Poisons Board; and this confirms my earlier statement that no objection is taken to reasonable controls designed solely to protect the public. The standing committee should cover the whole field of public health hazards and there should not be difficulty in defining its relation to the authorities that now are responsible for some form of control.A new function would be the consideration of those hazards arising from chemicals whose harmlessness has not been reasonably proved. This is an important problem and, as it is likely to become of increasing magnitude, the earlier it is considered the better. It is also a very controversial problem, especially as regards food. I propose, therefore, now to consider chemicals in foods, being sure that hazards from chemicals in other materials can be fitted in on similar and easier lines. Our present laws make it an offence to add any substance to any food so as to render The idea of a permanent or standing body is not new.278 ADDRESS OF THE RETIRING PRESIDENT [Vol. 75 the food injurious to health.There is little direct evidence on the matter, but it is thought t o have worked reasonably well in the past, and many people would like the position to con- tinue. Some of us, however, consider that the time is rapidly coming, if not already here, when we must go a little further. Manufacturers of food are continually looking for some substance that will perform a particular function in improving their products , and chemical manufacturers are often able to supply something that will do the job. New chemicals may be found to have particular properties that could be useful in improving food, and the makers will doubtless advocate their use for that purpose. All these are legitimate objects and make for technological progress. But the substance chosen for use may be quite different in composition from any normal ingredient of food, and its fate and effect in the human body may be quite unpredictable.Such an oil has been taken internally as a medicine by many people in large amounts for long periods, and when of pharmaceutical quality it might have been presumed to be perfectly harmless as an ingredient of food, for which it is an efficient emulsifier. Recently it was found that in an emulsified form mineral oils seriously affect the absorption and utilisation by the body of some of the vitamins and provitamins, with the resulting possibility of deficiency effects. A further risk with such oils is that impure grades have been found to contain carcinogens, and once an oil has been added to food it is difficult, if not impossible, to ascertain the grade used.For thesc reasons restrictions were placed by Order on the use of mineral oil in food. At the time the Order was made there was no extensive use in food, and in consequence few manufacturers were affected and little dislocation of trade occurred. It might happen, however, that a particular substance was used on a largescale before it was found to be harmful, and any sudden embargo on its use might cause considerable trade embarrassment. An example to illustrate this point is that of nitrogen trichloride (Agene) used for treating flour. This substance had gained very widespread use before it was discovered that the treated flour contained about 2 parts per million of a potentially toxic substance, methionine sulphoximine. This substance produced substantial physio- logical effects in dogs, rabbits and ferrets; but the amount that might be consumed by a man in a year is extremely small and may well be within the ineffective dosage range.The only difference between the protagonists for and against the use of nitrogen trichloride is whether the margin of safety is wide enough. I t might, however, have been found that the treated flour was definitely harmful to man, in which event the question of banning its use might have been acute. But what was found was that neither its harmlessness nor its harmfulness to man was proved; nevertheless it is pertinent to mention that, when an officially appointed committee reported in 1950 on improvers in flour, the Ministry of Food, the Ministry of Health and the milling industry accepted the recommendation that it was desirable eventually to discontinue the use of nitrogen trichloride and to use chlorine dioxide instead.In considering any action to be taken on chemicals in food, a case can be made out for making a distinction between those that are already in use and new ones that might be suggested for use. To deal-with the latter first, I would maintain that it is reasonable to insist that all new substances should pass appropriate pharmacological tests before being used for purposes that might otherwise involve a possible public health hazard. The responsibility for carrying out those tests should, in my view, rest upon those who make the article for such use or upon those who wish to use it for that purpose or upon both.The first is that for many years it has been an offence to add any substance to any food so as to render the food injurious to health. The second is that if a person is charged with unlawfully using a harmful substance, he has the defence that he did not know, and could not with reasonable diligence have ascertained, that it was harmful as used. I think the time has come to regard reasonable diligence as including the necessity of testing pharmaco- logically any novel substance to be used in or on the human body. As regards the tests to be applied, it should be the responsibility of the standing committee to issue them and to assess officially the results obtained. In doing so, the relative pharmaco- logical effects of the substance should clearly be related to the amount that is likely to be taken.Professor Frazer has suggested (E'ndeavour, 1953, 12, 43) that dosage levels can be classified as ineffective, effective, toxic and lethal, and with man the general ratio of these is approximately 1 :10:100:1000. He suggests that an acceptable dosage level of a chemical Consider the recent history of mineral oil in food. In fixing this responsibility, I have in mind two facts. This principle should, I think, apply to all consumer goods. This is a protection to him if not to the person harmed.May, 19531 ADDRESS OF THE RETIRING PRESIDENT 279 to be used in food should be one-tenth of the ineffective dosage level, calculated as milligrams per kilogram of body weight. He, therefore, arrives at the following table- Approximate dose Dosage group Result relationship Lethal Death .. . . . . .. .. .. .. 10,000 Toxic Demonstrable tissue damage . . .. . . 1,000 Effective Significant modification of structure or function . . 100 Ineffective No significant modification of structure or function 10 Acceptable - He is satisfied that pliarmacologists can specify appropriate short-term and long-term tests on different species of animals, which would enable non-cumulative dosage levels to be assessed. I t is known that several of the big organisations making food additives in this country recognise their responsibilities and carry out tests on these lines. It is desirable that such tests should be standardised and officially prescribed; clearly the right time for them to be carried out is before the substances are used and not while they are being used.It is not a new principle to apply special control to new substances. The Dangerous Drugs Acts place an embargo upon the manufacture and trade in certain drugs not known before a particular date; when satisfactory evidence is produced, the restrictions on a particular drug can be relaxed by Order. When considering pharmacological properties, it is necessary to refer to carcinogens, because everyone is in agreeincn t that no potentially carcinogenetic substance should be added to food. But here a difficulty arises; we do not always know when a particular sub- stance has this characteristic. At a recent meeting on the apparently increasing incidence of cancer in modern times, it was stated that after affection of a person by a carcinogenetic substance a latent period of up to ten years may elapse before any effects are noticed.Once the body has become affected the process cannot be halted, and it may be years before any detection is possible, so making uncertain the possible cause. Any substance, therefore, that is reasonably suspected of possible carcinogenetic properties should be excluded from food. There remains to consider what action, if any, should be taken with respect to chemicals a t present in use. These, I think, should be reviewed by the standing committee, and an official pronouncement made regarding those for which there are reasonable grounds for doubting their harmlessness. All others should be tentatively permitted, but should be reviewed if evidence becomes available of possible risk.In some instances it might be desirable to take steps to ensure that positive evidence is available upon which a review could be made. At the present time certain Research Associations are examining some classes of products; but the whole field needs covering and this can best be done under the general direction of the standing committee so that no hazard is overlooked. In certain instances it might be appropriate to prescribe the purity of the substance used. The first is artificial sweeteners. For many years there has been a need for such substances, and two found favour in this country, viz. , saccharin and dulcin. Neither of these was thoroughly tested toxicologically until recent years, but the results of extended tests have now been published.For saccharin there was no evidence that it was in any way harmful, at any rate in the maximum amounts ever likely to be consumed. Dulcin, however, showed harmful effects in different species of animals at certain concentrations and under specified conditions. If the standing committee were in existence, it should review the evidence and decide whether it justified banning the use of dulcin. Such a pronouncement, whether for or against, would be of great value to the public and to industry. There are other artificial sweeteners that have been proposed for use, e.g., P4000, and as far as this country is concerned they may be regarded as new chemicals. P4000 was advertised abroad as completely harmless to humans. The tests used to justify this statement were not disclosed, and many people were chary of accepting the assurance on the grounds that a substance containing nitro- groups, and which at high concentrations was a local anaesthetic, must be subjected to unequivocal tests before its use could be permitted in food.Later, more extended tests were carried out in the United States, and harmful effects were produced in animals. This shows the importance of prescribing the tests to be employed. Under my suggestions, P 4000 would not be permitted for use in food until the standing committee had reviewed the results of adequate tests. I have already mentioned some of the hazards that might occur from their use and the lack of complete 1 I will illustrate the suggested action by examples of two types of chemicals.The second illustration that I should like to give is that of food colours.280 ADDRESS OF THE RETIRING PRESIDENT [Vol. 78 knowledge of their fate in the human body. A sub-committee of the Food Standards Committee is dealing with preservatives, etc., and this includes food colours. This sub- committee has not yet reported and the nature of any recommendations that may eventually be made cannot be presumed. It is, however, carrying out in a limited field the functions that I think the standing committee should perform for the whole of the field. Without anticipating any conclusions of this sub-committee, I will illustrate how food colours fit in with my general picture. They are produced by chemical reactions from intermediates, some of which are known to produce toxic effects. For this reason colour manufacturers take particular care to supply for use in food those that are as pure as possible and free from harmful impurities. A certain amount of pharmacological work has been carried out on some of these colours over many years and in many countries; but the results of such work can be applied only to a colour conforming to the specification of the sample tested.Some of the colours used in food are produced in less pure grades for purposes other than food, and in order to avoid any unnecessary risk it is important that a colour permitted for use in food should conform to an appropriate chemical specification. This can only be achieved by defining that specification, and this leads to the conclusion, as I think inescapably, that a list of permitted colours is essential, each with its definite chemical specification. At present our law specifies a short list of prohibited colours and any colour not on that list may be used in food, unless its use can be challenged under the Food and Drugs Act. If it should be thought proper to protect the public more fully from a risk that might arise from harmful colours, then inevitably the policy must be changed to a permitted list specifying those colours that, after examination of the evidence, are considered suitable for use. It should be the function of the standing committee to compile this list from the colours now in use having regard to the pharmacological evidence available. No new colour should be added to the list without having been adequately tested and approved, and any colour on the list found to have harmful effects should be withdrawn at once or, according to the risk, after a specified time. Provision could easily be made for notification of intention and an opportunity given for commercial interests to express their views. Colours in cosmetics should also be under review and there should be legal powers of control. This, I think, would be accepted by industry, as it would provide a protection for manufacturers from a risk that, although small, is ever present as a civil liability to them. Some hundreds of synthetic food colours are or have been used for colouring food. The field that I have attempted to survey is a large one, and difficult because it is con- cerned with a great number of risks, most of which, in themselves, are relatively small. Taken together they cannot be ignored, and the public is entitled to expect that consideration will be given to its protection. I hope that my survey will help to give a picture of the whole field and that what I have suggested is a rational, realistic and reasonable implementation of the policy of the Advisory Council on Scientific Policy.

ISSN:0003-2654    

DOI:10.1039/AN9537800271

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

May, 19631 ANNIVERSARY DISXER 281 Anniversary Dinner IN the evening following the Annual General Meeting, a Dinner to celebrate the seventy- ninth anniversary of the Society was held, by kind permission of the Master, in the Hall of the Worshipful Society of Apothecaries of London, Blackfriars Lane, London, E.C.4. The members and guests, numbering 100, were received by the President, Dr. J. R. Nicholls, C.B.E., F.R.I.C., and Mrs. Nicholls. The President afterwards took the Chair at the Dinner. The guests of the Society and of the President included: Dr. Charles Hill, M.A., M.D., D.P.H., LL.D., M.P., and Mrs. Hill; H. W. Cremer, C.B.E., M.Sc., M.I.Chem.E., M.Inst.F., F.R.I.C. ; Norman C. Wright, B.A., D.Sc., Ph.D., F.R.I.C., and Mrs. Wright; L. H. Lampitt, D.Sc., F.R.I.C., M.I.Chem.E., and Mrs.Lampitt ; Stanley Robson, M.Sc., D.I.C., M.I.Chem.E., M.I.M.M., F.R.I.C., and Mrs. Robson; G. Roche Lynch, O.B.E., M.B., B.S., D.P.H., F.C.G.I., L.M.S.S.A., F.R.I.C. ; Sir E. John Russell, O.B.E., D.Sc., F.R.S., and Lady Russell; The Hon. Mr. Justice Lloyd-Jacob, and Lady Lloyd-Jacob; Mrs. S. B. R. David, B.Sc., A.R.C.S., -4.R.I.C.; R. A. Beck; J. Lee; and the Clerk of the Worshipful Society of Apothecaries, E. Busby. After the loyal toast had been honoured, the President, Dr. Nicholls, presented Bernard Dyer Memorial Medals to the first two Medallists, who had given the first two Bernard Dyer Memorial Lectures to the Society and were present as guests. He recalled that Bernard Dyer had been one of the original members of the Society, remaining a member for 73 years until his death in 1948.He was an agricultural chemist, which made it most appropriate that the first Memorial lecturer should have been Sir E. John Russell, who was also an agricultural chemist. The President then presented the Medal to Sir John. Sir John Russell, in thanking the President, said that he had happy memories of Bernard Dyer, Chaston Chapman and Augustus Voelcker, and had enjoyed a long connection with the Society. Before presenting the second Medal to the Hon. Mr. Justice Lloyd-Jacob, the President said that the Bernard Dyer Memorial Medal had been designed by Mr. T. H. Paget, who had been responsible for the obverse designs of the coins and medals of the reign of King George VI. He much regretted that Mr. Paget had been unable to attend the dinner owing to illness.The President then presented the Medal to Mr. Justice Lloyd-Jacob, and said that it had been only chance that had turned him from chemistry to the legal profession. The Hon. Mr. Justice Lloyd-Jacob, in thanking the President, said that he found himself in the position of a junior following an eminent leader, Sir John Russell. His own connection with the Society was more recent, being with members who had given evidence in the court in which he sat. Mr. H. W. Cremer, President of the Royal Institute of Chemistry, proposed the toast of the Society. He said he was impressed by the large number of members of the Society who were also Fellows or Associates of the Royal Institute of Chemistry. He complimented the Society, now in its eightieth year, on its growth; there were now many more members con- cerned with analysis of articles other than foods, and in the subject groups of the Society and in the topics chosen for lectures the Society’s field had been widely extendedof recent years.The Society had played a very full part in the Analytical Congress at Oxford in September, 1952. He paid tribute to the President elect, Dr. Kent-Jones, and said that on his becoming President the Royal Institute of Chemistry had lost a greatly honoured Honorary Treasurer. In that capacity Dr. Kent- Jones had shown great wisdom, sympathy and understanding. The Institute’s Benevolent Fund had benefited enormously by the sympathy with which Dr. Kent-Jones sought to relieve those in distress. He wished the Society every success, and coupled his toast with the name of the President.The President, Dr. Nicholls, in reply, thanked Mr. Cremer for his appreciative remarks about the Society. He, too, knew that the majority of the members of the Society were members of the Royal Institute of Chemistry. The Institute was a qualifying body and, as such, might be described mathematically as the lowest common denominator of chemistry ; if, so, analytical chemistry was the greatest common measure in all other branches of chemistry. Dr. A. J. Amos, in proposing the toast of the guests, said that it was fitting that he should refer first to Dr. Charles Hill. Chemists would recognise in him the phenomenon of allotropy-existence in several forms of one and the same body; first he appeared as Secretary282 ANNIVERSARY DINNER [vol.78 to the British Medical Association, then as the “Radio Doctor,’’ and then he reappeared as the Parliamentary Secretary to the Ministry of Food. There had been a great deal of liaison between our Society and the Ministry of Food. Dr. Hill’s training, although in medicine, had been scientific, so that he understood the analyst’s language. The Ministry had in many ways earned the gratitude of the Food Industry. He was sorry that the Ministry’s very valuable Advisory Service had ceased. Dr. Norman Wright, Scientific Adviser to the Ministry of Food, had been a most successful Chairman of the Food Standards Committee, on which there was great scope for co-operation between the Ministry, the Food Trade and the analyst.Dr. Amos welcomed Mr. Cremer both as chemist and engineer; his Presidency of the Royal Institute of Chemistry was linked with his Past Presidency of the Institution of Chemical Engineers-a record which he believed was unique. Dr. Lampit t represented the President of the Society of Chemical Industry; the choice of him as proxy was very welcome, as he had been responsible for the formation of that Society’s Food Group. Mr. Stanley Robson, the President of the Institution of Chemical Engineers, was also doubly welcome, for he was a Past President of the Society of Chemical Industry. Dr. Roche Lynch, representing the Master of the Worshipful Society of Apothecaries, was both host and guest, for he was the immediate Past Master of the Society of Apothecaries and a Past President of the Society of Public Analysts.He was pleased to welcome the Bernard Dyer Memorial Medallists as guests ; Sir John Russell’s outstanding contributions to analysis were well known, and Mr. Justice Lloyd- Jacob might well have been as eminent an analyst as he was a judge. Finally, but by no means least, he welcomed the ladies, without whose presence the Dinner would not have been complete. The toast of the guests was coupled with the name of Dr. Charles Hill. Dr. Charles Hill, replying on behalf of the guests, said that he thanked the Society in general, and the President in particular, for the valuable co-operation they had extended to the Ministry of Food in the past 13 or 14 years. He understood Dr. Amos’s regret a t the disappearance of the Advisory Service, but although as analysts they might be sorry that the Ministry’s functions grew less in number, as ordinary citizens they might well hope for the speedy departure of the whole Ministry. He felt sure that the work of the Society would succeed just as well in the absence of the Ministry. The guests had appreciated and enjoyed the Society’s hospitality. The President, Dr. Nicholls, then invested Dr. Kent- Jones with the presidential badge and wished him success during his term of office. Dr. Kent-Jones expressed his thanks to the Society for the honour it had conferred upon him.

ISSN:0003-2654    

DOI:10.1039/AN9537800281

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

May, 19531 DICKINSON : EVALUATION OF ANTI-VIRAL COMPOUNDS 283 Evaluation of Anti-Viral Compounds BY LOIS DICKINSON (Presented at the meeting of the Biological Methods Group on Friday, October 26th, 1951) The desiderata and difficulties involved in any scheme of testing for anti-viral compounds are discussed and illustrated by the use of one such scheme making use of (a) a bacteriophage of Pseudomonas pyocyanea, (b) influenza-A virus, (c) vaccinia virus, (d) sheep abortion virus and (e) Rous sarcoma virus; (6) to (e) are in o‘uo tests. Extended to in vivo work, the tests cover influenza, ectromelia and mouse pneumonitis (Nigg) viruses in mice and Rous sarcoma virus in chicks. Correlation between the in ovo and mouse tests has been found for Nigg virus. IN this paper viruses are defined as “organisms or particles ranging in size from about 10 mp to about 300 mp with a common property of requiring the presence of living host cells (animal or bacterial) for growth.” Current views on the nature of viruses range from conceptions of them as degraded bacteria to the idea that they are gene-like structures, which direct the infected cells’ metabolism to produce more virus particles.The evaluation of possible anti-viral compounds is complicated by the fact that, except for the larger viruses, there is no known active drug that can be used as a standard to justify a scheme of testing. Furthermore, all tests have to be in vivo tests, with the complication that toxicity to the host (bacteria, egg, tissue culture or animal cell) has to be considered from the beginning.The fact that viruses are intracellular parasites does not mean that the task is impossible. Drugs could conceivably act by- (i) direct inactivation of extracellular virus, (ii) prevention of adsorption of virus on the cell, or its penetration into the cell, (iii) prevention of release of virus from infected host cells, or (iv) inhibition of the multiplication of intracellular virus. The intracellular approach is perhaps the most important and certainly the most fascinating one. One virus particle enters a cell and, after a certain, definite interval of time, many particles, up to 300 for some bacteriophages (i.e., bacterial viruses), come out. We know almost nothing about virus metabolism, if any, or indeed whether the smallest viruses (about 10mp in size) are similar to the largest ones (about 250mp).Even in the group of the largest ones, the viruses differ considerably in their response to the various drugs, in the experimental animal and in man (Table I). The variation would be much TABLE I CHEMOTHERAPY OF THE LARGER VIRUSES (Host not indicated) Sulphon- Chloro- Aureo- Terra- Virus Acridines Penicillin amides PABA mycetin mycin mycin L.G.V. .. * * o,+ + + Stimulates + ++ ++ Trachoma . . .. ... k + ... + + ... Psittacosis . . .. & + 0 0 + + ... Feline pneumonitis . . + +_ 0 ... & ... ... Mouse pneumonitis . . 0 3- 3- 0 ++ +++ +++ Sheep abortion . . ... 0 0 0 ++ +++ +++ (most strains) 0 = No action; k, +, + +, + + + = various degrees of activity. Data taken from Findlayl and Dickinson and Inkley.2 greater if the tests had been carried out with different strains of each virus against a range of hosts.Hence the problem of evaluating anti-viral compounds resolves itself into the choice of virus and host, since it is obviously impossible to test every virus in various host animals.284 DICKINSON EVALUATION OF ANTI-VIRAL COMPOUNDS [Vol. 78 Man would be the ideal host and, in fact, for the common cold he is used as the experimental animal, although an inconvenient and expensive one. One might expect mammals to give a better host-picture than the chick embryo or a bacterial cell, but a t the moment there are no grounds for such a view. Therefore, most workers choose the convenient laboratory hosts, bacteria, fertile eggs and mice. There appear to be as many different testing procedures as there are papers in the literature on virus chemotherapy. We have devised our own scheme (Fig.l), and it is this scheme that is discussed here. It is far from perfect, still tentative, and we are prepared to alter it at any time. No one scheme can hope to cover every virus infection; it must be a compromise between the ideal and the practical. Any virus used must obviously be conveniently handled in the laboratory, i.e., it must not be very highly infectious to workers or to stock animals. The host animals must be available in quantity and must be free, as far as possible, from latent infections; pure-line strains are advantageous. The test viruses should be easily titrated and reasonably stable, so that stocks at constant titre are at hand.Some viruses, e.g., sheep abortion virus, maintain their titre almost indefinitely at -20" C, but others, e.g., mouse pneumonitis (Nigg) virus, lose activity even at -70" C. Freeze-drying is quite satisfactory for virus preservation, but there is usually a considerable loss of titre during the process. Owing to the risk of cross infection of animals, it is not good policy to work with many viruses at once. On the other hand, it is not wise to limit the testing to only one host - virus system, for it is not known whether or not different small viruses have different points of attack; the individual response of the larger viruses does vary. We therefore test all compounds against a bacteriophage and regard the phage merely as one convenient test SCREENING All Compounds Tested INFLUENZA A VIRUS BACTERIOPHAGE I L (in eggs) 1 v) (0 - 2 a (in mice) (in chicks) RESPIRATORY POX TUMOUR Evaluation of possible anti-viral agents Fig.1. ABORTION VIRUS (in eggs) 1 I NlGG VIRUS (in mice) LARGE VIRUSES virus; one junior assistant can carry out hundreds of such tests. For safety, however, many selected compounds are tested against other viruses, an attempt being made to cover the main groups of viruses as far as they can be classified at present, e.g., the respiratory, pox and tumour groups of infections.May, 19531 DICKINSON : EVALUATION OF ANTI-VIRAL COMPOUNDS 285 This has several advantages. The host cell is particularly resistant to drug action and grows readily in a simple medium of ammonium lactate and salts.The test itself is very ~imple.~ The drug is diluted in lactate medium and inoculated with a heavy inoculum of host cells plus about 20 phage particles per ml. After incubation for 24 hours, a control culture contains about los phage particles per ml. A loopful of such a culture, when spotted on a previously prepared plate of nutrient agar seeded with the host cell, lyses the area on which it has been spotted. If the phage has not multiplied, and provided that the host cells in the tube have grown (as observed visually), there is an area of “no lysis.” With this system it is fairly easy to find out how the drugs are acting. One difficulty in this test has been that compounds are often active in the synthetic medium, but not when the test is carried out in broth.This is easy to understand when the drugs act by a direct viricidal effect, since proteins do “protect” many viruses. Sometimes, however, this inactivation by broth occurs when the drug concerned is neither acting by “contact” nor stimulating host growth. In addition, many compounds (and all new types of molecules) are tested against influenza-A virus in fertile eggs, regardless of the phage test results. Influenza A typifies a large and important group of viruses (the respiratory group) and, in addition, is in world-wide use as a test virus. Compounds, e.g. , chloromycetin-like compounds, that are expected to show activity against the larger viruses are tested against the virus of sheep abortion.2 The phage test would not be expected to detect such activity and, in fact, does not, as the phage is a small virus. The sheep abortion virus is most satisfactory for chemotherapy experiments in eggs.I t is very stable and gives clear and consistent lesions on the chorioallantoic membrane of the developing chick embryo. The other virus used in this group is the virus of mouse pneumonitis (Nigg). We cover the pox group of viruses by egg tests against vaccinia virus, and then by ectromelia virus. Both these are stable and easy to estimate on the chorioallantoic membrane. The tumour-producing group of viruses is typified by Rous sarcoma 1 virus. For the bacteriophage we use a phage of Pseudomonas pyocyanea. Compounds active against phage are tested against other viruses. 112 OVO TESTING- For tests in eggs against influenza-A virus, both drug and virus (100 egg-infective doses) are given via the allantoic sac, the drug being given 1 hour before the virus.3 This test is so simple that influenza A has become our main virus for general screening. After incubation for 48 hours, the increase in virus is judged by the haemagglutination of fowl red blood cells by the allantoic fluid.The merits of this test are- (i) I t is simple and rapid. (ii) I t should indicate activity by contact, prevention of adsorption, release of virus or multiplication of virus. We believe that a compound should be active in this test if it has any activity at all. (iii) The allantoic sac, the extra-embryonic bladder of the embryo, withstands larger amounts of drugs than can be administered by any other route.The test may be modified so that the virus is given first and the drug several hours afterwards but, even so, it is difficult to exclude a contact action of the drug on the virus. For example, certain plant extracts are active 4 hours after infection3; however, the tannins in the extract inactivate the virus in the allantoic fluid, which is virtually protein-free. Incidentally, the active plant extracts are highly active against phage, and this effect is also one of direct contact. When the tannins are precipitated by serum or phenazone, the extracts are inactive against both phage and influenza. An alternative route, to avoid this type of contact action, is to give the drug via the yolk sac. Unfortunately, drugs are much more toxic by this route and contamination is a more serious problem, although addition of penicillin and streptomycin (200 units of each per millilitre) usually prevents any trouble if the material cannot readily be sterilised.There are two doubtful features in this yolk-sac test, namely, doubt as to the permeability of the embryonic membranes compared with that of mammalian cells, and doubt whether an effective drug concentration can be attained in the allantoic sac (Le., the site of virus proliferation), when drugs are given via the yolk sac. So far, although we have had com- pounds active in the allantoic sac, none have been active when given via the yolk sac.286 DICKINSON EVALUATION OF ANTI-VIRAL COMPOUNDS [Vol. 78 Ginsberg, Goebel and Horsfall4 found that a polysaccharide given via the yolk sac only reached the allantoic sac in 50 per cent.of the eggs; it prevented influenza growth in these eggs. The compounds we have tested may have been too toxic or not active enough to give the required concentration in the allantoic sac ; this applies particularly to impure antibiotics or other natural products. Perhaps they are inactivated or broken down in the yolk sac. To avoid the difficulties just described, influenza-A virus can be adapted to grow on the chorioallantoic membrane and the drug can be given via the yolk sac. This type of test works well for the larger viruses. For example, abortion and Nigg viruses are inhibited by chloromycetin, aureomycin and terramycin.2 Other workers in this field use the yolk-sac route for infection and treatment, judging activity of compounds by their ability to prolong the survival of the embryos, but we find the membrane technique more satisfactory.Difficulties arise when Rous sarcoma virus is used in this type of test because of the occasional irregularities of the response. Sometimes, enormous bean-sized sarcoma develop, even without any obvious damage to the membrane to account for it, and it is difficult to know whether one large tumour is equivalent to many little ones. We therefore fix, dry and weigh the membrane for quantitative asse~srnent.~ The egg tests offer the following advantages- (i) Small amounts of drug are required; usually a single dose. The compound cannot be excreted from the egg and is not normally inactivated. (ii) Eggs have no known latent viruses of their own, provided that they come from a reliable source.(iii) The tests are rapidly made. (iv) The system is very simple. Any compounds found active in the egg tests are investigated further in animals. In vivo TESTING- If a compound is active in eggs against influenza-A virus, it is tested in mice against the same virus adapted to mouse lungs. The virus is given intranasally and the drugs subcutaneously; results are assessed on deaths, survival times and on the extent of pulmonary lesions. When a drug is active against vaccinia and ectromelia viruses in eggs, it is examined against ectromelia in mice. Ectromelia or “mouse pox” virus, given intraperitoneally to mice, causes death within 7 days. It is a highly infective natural pathogen of mice, and great care must be taken to prevent the spread of infection.Compounds suppressing the growth of sheep abortion and Nigg viruses are tested against Nigg virus in mice by a similar technique to that used in the influenza test. For the Nigg virus, results in eggs and mice agree well with each other (Table 11) and the clinical picture TABLE I1 CHEMOTHERAPY OF THE LARGER VIRUSES Inhibitory dose, mg per egg, for Drug Abortion virus Nigg virus f A \ Chloromycetin . . .. 1.0 2.0 Aureomycin . . .. 0.25 0.25 Terramycin . . .. 0.06 0.06 Penicillin .. . . Inactive 2,000 u. 2,000 u. Sulphathiazole . . .. ~7 14-7 14-7 p-Aminobenzoic acid . . 99 27.4 Inactive 13.7 Activity in mice against Nigg virus (drug given subcutaneously from day of infection) + + +++ ( +++ ( + + 0 (0-02 mg per g per day) (4,000 u.per mouse per day) (0-2 mg per g per day) (2 mg per g per day, orally) 73 97 ) 1 + = Prolongation of life only; + + = no deaths, but lungs involved; +++ = no deaths, lungs not involved. in the treatment of the larger viruses is in agreement with these results. It is for this reason that we feel that the egg test should pick out a potential anti-viral compound in the other groups of viruses. When the Rous sarcoma virus is used, two aspects of chemotherapy, the anti-viral and the anti-tumour, must be distinguished. The egg test should pick out a potential anti- viral agent, whereas the chick test should reveal both types of activity. Many compoundsMay, 19531 HARRIS 287 are therefore tested in young chicks regardless of the results of the egg test. We have found several anti-mitotic agents to be active in the chick test, but inactive in the egg test6 It will be seen that we have not included a very small virus in this scheme. Nigg and abortion viruses are in the 200 to 300-mp size group, vaccinia is about 150mp, and influenza A about 100mp. Rous sarcoma is 75mp and Pseudomomzs pyocyanea phage about 60 mp. Foot-and-mouth disease and poliomyelitis viruses are only about 10 mp in size. If necessary, however, we could include a mouse encephalomyelitis virus (10 mp) in the scheme, but we should be satisfied if we found anything of use in the treatment of viruses in the groups we are studying at present. The larger ones are already fairly well covered and give some hope that the task is not impossible. The latent infections that may arise from such treatments are another problem. REFERENCES 1. 2. 3. 4. 6. Findlay, G. M., J. Pharm. Pharmacol., 1951, 3, 193. Dickinson, L., and Inkley, G. W., Nature, 1951, 168, 37. Chantrill, B. H., Coulthard, C. E., Dickinson, L., Inkley, G. W., Morris, W., and Pyle, A. H. J., Ginsberg, H. S., Goebel, W. F., and Horsfall, F., J. Exp. Med., 1948, 87, 385 and 411. Dickinson, L., and Thompson, M. J., Brit. J. Plzarmacol., 1952, 7, 277. J. Gen. Microbiol., 1952, 6, 74. RESEARCH DEPARTMENT (VIRUS SECTION) BOOTS PURE DRUG Co. LTD. NOTTINGHAM October 17th, 1952

ISSN:0003-2654    

DOI:10.1039/AN9537800283

出版商:RSC    

年代:1953

数据来源: RSC

摘要:

May, 19531 HARRIS 287 The Colorimetric Determination of Fructose and Sorbose BY F. J. T. HARRIS* When a fructose or sorbose solution is heated with the Folin - Denis reagent and tri-sodium phosphate a blue colour is produced. This colour can be used in determining the amount of sugar in the solution, with an accuracy of about 2 per cent. Sugars other than fructose or sorbose give much fainter colours. DURING the course of other work the need arose for a method of determining fructose in the presence of small amounts of other sugars and the method of Englis and Miles1 was investigated and extended to other sugars. When fructose is mixed with the Folin - Denis phosphotungstic - phosphomolybdate reagent and tri-sodium phosphate, a blue colour develops on heating in boiling water.This colour is also produced by other sugars, but, except for sorbose, with them the colour is much less intense. EXPERIMENTAL The colour produced was measured on a Spekker absorptiometer. Ten millilitres of a 12.5 per cent. fructose solution and 5 ml of the phosphotungstic - phosphomolybdate reagent were mixed in a 100-ml calibrated flask, which was set aside for 4 minutes. Ten millilitres of a 0.5 M tri-sodium phosphate solution were added and the flask was placed in boiling water for 10 minutes. It was found that the transmittance of the mixture decreased at the longer wavelengths, so a red No. 608 filter was used for further work (see Table I). TABLE I The mixture was then cooled and diluted to 100 ml. EFFECT OF FILTERS ON OPTICAL DENSITY MEASURED IN A l-cm CELL Filter No... .. .. .. 601 602 603 604 605 606 607 608 Approximate wavelength at peak, mp 431 467 489 515 548 570 598 682 Optical density with 0.125 g of fructose 0.112 0.141 0.158 0.172 0.199 0.210 0.228 0.246 Optical density of blank solution . . 0.011 - - 0.013 - 0.015 - 0.020 * Present address: Evans Adlard & Co. Ltd., Postlip Mills, Winchcombe, Cheltenham.288 HARRIS : THE COLORIR.IETRIC DETERMINATIOK [Vol. 78 The effect of varying the interval between the addition of the reagent and the addition of the phosphate was investigated. The final optical density of the solution increased as the interval increased up to 5 minutes and then decreased with further increase in the interval (see Table 11). A 5-minute interval was used in all subsequent work instead of the 4-minute interval specified by Englis and Mi1es.l The tri-sodium phosphate solution used was 0.5 M (19 per cent.w/v) instead of 20 per cent. as used by the American workers. 0.3 0.2 x C T I Y) - a - Y 0" 0. I 0 Too little phosphate _ - . ---_ - . m 5 10 I S 20 Reagent, rnl Fig. 1. Effect of Folin-Denis reagent and phosphate on optical density. Curve A, 5 ml of phosphate; curve 33, 10 ml of phosphate; curve C, 20 ml of phosphate The stability of the colour was investigated and it was found that the decrease in optical density proceeded steadily, but was only 23 to 3 per cent. over a period of 21& hours. The decrease in, say, 1 hour is consequently negligible. The variation in the optical density produced by varying the amounts of reagent and phosphate was investigated.An increase in the amount of reagent used increased the colour, whilst increase in the amount of phosphate decreased the colour (see Fig. 1). If the volume TABLE I1 EFFECT OF VARIATION OF IKTERVAL BETWEEK ADDITIONS OF KEAGEKT 1-cm cell, No. 608 filter Interval, minutes . . . . . . .. 2 4 5 8 10 Optical density of blank solution . . .. - 0.020 0.021 - 0.021 of the phosphate was less than that of the reagent, or if the volume of phosphate was more than about four times that of the reagent, results were erratic and the green colour produced varied greatly. The amounts finally adopted were 5 ml of reagent and 10 ml of phosphate. AND PHOSPHATE Optical density of 0.125 g of fructose . . 0.210 0-246 0.251 0.226 0.212May, 19531 OF FRUCTOSE AND SORBOSE 289 0" Variation in time of heating was also investigated.The optical density increased as the time of heating increased, but the greatest optical density was almost reached in about 10 minutes. '>I2 (b) lnulin Starch TABLE I11 EFFECT OF TIME OF HEATING IN BOILING WATER Time, minutes . . .. .. .. 0 2 6 7 10 12 16 30 Optical density of 0-126 g of fructose less blank value, measured in a Variations in the volume of the sugar solution caused variations in the final optical l-cm cell . . .. . . . . 0.011 0.174 0.205 0.220 0.241 0-237 0.241 0.264 density, so the volume of sugar solution was standardised at 10ml. lrehalose, Celloblose, Lactose 0.2 =5 Rhamnose 1 0.4 Wt of Sugar, g Fig. 2. Optical densities produced by various sugars, with 1-cm cell and No.608 filter. (a), C, sugars; (b), C>, sugars; (c) C,, sugars; (d), C, sugars290 HARRIS [Vol. 78 METHOD REAGEKTS- and 20 g of phosphomolybdic acid, add 100 g of phosphoric acid and TOO ml of water. for 2 hours, cool, filter if necessary and dilute to 1 litre. water and dilute to 1 litre. Folin - Denis phosphotungstic - phosphomolybdate reagent2-l'o 100 g of sodium tungstate Boil Tri-sodium Phosphate solution, 0-5 M-Dissolve 190 g of pure tri-sodium phosphate in PROCEDURE- After 5 minutes, add 10 ml of the 0.5 M tri-sodium phosphate solution and place the flask in boiling water. After 10 minutes remove the flask from the boiling water and at once dilute the solution with cold distilled water to about 95 ml. Allow to cool, dilute to the mark and measure the optical density of the solution (compared with water) in a 1 or 4-cm cell using a red No.608 filter. Prepare a comparison solution by substituting 10ml of water for the 10ml of sugar solution. Mix 10 ml of sugar solution and 5 ml of the Folin - Denis reagent. RE s ULTS The method was tried with starch, raffinose, inulin, maltose, trehalose, cellobiose, lactose, sucrose, sorbose , fructose, galactose, mannose, glucose, xylose, arabinose and rhamnose. The sugars used were nearly all either of analytical reagent grade or bacteriologically pure. I t was found (see Tables IV and V and Fig. 2) that the only two ketohexoses investigated (sorbose and fructose) gave identical optical density - concentration graphs. The other sugars all gave much less colour. Different batches of reagent were found to give slightly different results. TABLE IV OPTICAL DENSITY OF SORBOSE AND FRUCTOSE IN A 4-cm CELL Amount of sugar, g . . . . 0.02 0.04 0.06 0.08 Optical density . . .. . . 0.236 0.424 0.600 0.7'70 TABLE Y OPTICAL DENSITY OF 0.1 g OF VARIOUS SUGARS IN A 4-cm CELL Sugar Starch . . . . Raffinose . . Inulin . . .. Maltose .. Trchalose . . Cellobiose . . Lactose .. Optical density . . . . 0.020 . . . . 0.010 .. . . 0.061 . . . . 0.141 . . . . 0.042 . . . . 0.042 .. . . 0.042 0.10 0.924 Sugar Optical density Sucrose .. .. . . 0*005 Galactose . . .. . . 0.210 Mannose . . .. . . 0.132 Glucose . . . . . . 0.082 Xylose. . . . . . . . 0.269 Arabinose . . . . . . 0.248 Rhamnose . . .. . . 0.079 In a number of determinations with known amounts of fructose the error was found to be about 1 to 2 per cent. REFERENCES 1. 2. SAMUEL HANSON & SON, LTD. Englis, L). T., and Miles, J. W., Anal. Chem., 1949, 21, 583. Folin, O., and Denis, W. J., J . Bid. Chenz., 1912, 12, 239. RESEARCH DEPARTMENT TODDINGTON, GLOS. September 25th, 1952

ISSN:0003-2654    

DOI:10.1039/AN9537800287

出版商:RSC    

年代:1953

数据来源: RSC