摘要:

Proceedinas ~ - - -~of the Analytical Division ofThe Chemical SocietyCONTENTS101 RIC Centenary and CS/RICAnnual Chemical Congress102 Reports o f Meetings103 Summaries of Papers103108 'Gas Chromatography in the'Use of Enzymes in AnalyticalChemistry'Oil Industry'11 2 'Fourth Annual Reports onAnalytical Atomic SpectroscopySymposium'115 Safety i n Analytical Laboratories:Preparing EmergencyProcedures f o r a ChemicalLaboratory118 Fourth SAC Conference125 Revised British Standard f o rGraduated Pipettes125 International AnalyticalCommission of t h e Comiti!International des DerivesTensio-actifs126 Technicon Scholarship126 Chemical Society Library127 Conferences and Meetings128 Courses129 Publications Received130 Analytical Division DiaryVolume 14 No 5 Pages 101 -1 30 May 197PADS DZJSSN 0306-1 39614(5) 101 -1 30( 1 977) May 1977PROCEEDINGSOF THEANALYTICAL DIVISION OF THE CHEMICAL SOCIETYOfficers of the Analytical Divisionof The Chemical SocietyPresidentD.W. WilsonHon. SecretaryP. G. W. CobbSecretaryMiss P. E. HutchinsonHon. Treasurer Hon. Assistant SecretariesJ. K. Foreman D. I. Coomber, O.B.E.; D. C. M. Squirrel1Editor, ProceedingsP. C. WestonProceedings is published by The Chemical Society.Editorial: The Director of Publications, The Chemical Society, Burlington House, London, W1 V OBN.Telephone 01 -734 9864. Telex 268001.Subscriptions (non-members): The Chemical Society, Publications Sales Office, Blackhorse Road,Letchworth, Hens., SG6 1 HN.Non-members can only be supplied with Proceedings as part of a combined subscription with The Analysfand Analytical Abstracts.(6 The Chemical Society 1977CS ATOMIC SPECTROSCOPY GROUPinvite applications for the1977 RANK HILGER SPECTROSCOPY PRIZEThe successful candidate will receive a prize to the value of f 75, part of which is tobe used for the purchase of a book(s) for presentation at the Group's AGM.Theaward will be judged on the basis of the candidate's contribution to analyticalatomic spectroscopy. The work need not be theoretical but could cover applic-ations, instrumental modification, accessories, improvements in technique or datahandling. The contribution need not have been published and candidate's wisheswith respect to publication will be respected.Intending candidates should (1) be under 30 years of age on December 31st,1977; (2) be resident in the United Kingdom; (3) submit, before May 31st, 1977,a summary of about 500 words, describing their contribution to the theory orpractice of atomic spectroscopy. The summary should be endorsed by a seniormember of the establishment in which the candidate is employed.Applications should be addressed to the Honorary Assistant Secretary, AtomicSpectroscopy Group, Analytical Division, The Chemical Society, Burlington House,London, W1 V OBN

ISSN:0306-1396    

DOI:10.1039/AD97714FX017

出版商:RSC    

年代:1977

数据来源: RSC

摘要:

Vol. 14 No. 5 May 1977 Proceedings of the Analytical Division of the Chemical Society RIC Centenary and CS/RlC Annual Chemical Congress Analytical Chemistry at the Science Museum The refurbished Chemistry Galleries a t the Science Museum in London were opened by HRH the Duke of Kent a t a reception held on March 28th, 1977, to coincide with the RIC Centenary celebrations. The analytical section of the Galleries includes apparatus devised for organic analysis by Lavoisier, Berzelius and Liebig, and apparatus for the determination of nitrogen, e.g., Schiff’s nitrometer, Knop’s azotometer, Hufner’s apparatus for urea and the equipment developed by Will and Varrentrap, Kjeldahl, Staedal and Gay-Lussac and Thknard.Also on display is apparatus for the deter- mination of molecular weight, a polarimeter, Pregl’s microanalysis apparatus, ultraviolet and visible spectrometers, a mass spectrometer and the infrared spectrometer developed by H.W. Thompson. An electron-diff raction camera built by L. E. Sutton et al. in 1947-49, and the gas-chromatography apparatus developed by Martin and James in 1951 are in the Galleries and the earliest surviving paper-chromato- graphy tank (reported in the first paper on the subject of paper chromatography by I<.Consden, A. H. Gordon and A. J. P. Martin in 1944) can be seen (photograph on p. 102). In addition there is a Hilger Spekker absorptiometer, X-ray diffraction and refracto- metry instruments, a polarograph and a large display of balances. The application of chemical analysis in the fields of archaeology and the conservation of works of art is demonstrated in a laboratory equipped with instruments and specimens, and methods of dating a 15th-century wood panel from Westminster Abbey and of detecting a fake T’ang horse are explained. (Science Museum photo.Crown Copyright) HRH the Duke of Kent with the Director of the Science Museum, Dr. Margaret Weston.Analytical Symposia The Analytical Division participated in the CS/RIC Annual Congress held a t University College, London from March 28th to April lst, 1977. The central theme of the Congress was “Chemistry in Our Lives,” and the AD organised two Symposia : “History of Analytical Chemis- try” on March 30th; and “Modern Methods of Speciation-Characterisation of Chemical Species” on March 31st.On March 30th, the following papers were presented : “History of American Analytical Chemistry,” by R. Belcher ; “From Assaying 101102 REPORTS OF MEETINGS Proc. Analyt. Div. Chem. Soc. to Analytical Chemistry: How an Art Became On March 31st, the first paper was the sixth a Science,” by F. Szabadvhry; “PAS of the Theophilus Redwood Lecture by Dr. D. R. Past,” by Miss J.D. Peden; “The Origin and Deans, entitled “Analysis with a Purpose,” Initial Development of Chemical Microscopy,” and a scroll was presented to Dr. Deans by the by R. H. Nuttall; “Irish Contributions to AD President, Mr. D. W. Wilson. Analytical Chemistry,” by D. Thorburn Burns ; The programme then continued with the following papers : “Metal Specific Detectors for Chemical Speciation Studies,” by J.C. Van Loon ; “Characterisation of Catalyst Sur- face Species by Electron Spectroscopy,” by D. M. Hercules; “Molecular Emission Cavity Analysis,” by A. Townshend; “FTNMR Spectroscopic Analysis through the Periodic Table,” by I. K. O’Neill; “The Application of Electrochemical Methods to the Study of Metal Species in Water,” by B. Fleet. The earliest surviving paper-chromatography tank, on display at the Science Museum. “Three Hundred Years of British Contributions to Atomic Spectroscopy for Chemical Analysis, ” by T. S. West; “William Crookes, Chemical News and Analysis,” by D. Betteridge; “The History of Organic Reagents,” by W. I. Stephen. Presentation of scroll by the A D President, MY. D. W . Wilson, to the sixth Theophilus Redwood Lecturer, Dr. D. R. Deans (L).

ISSN:0306-1396    

DOI:10.1039/AD9771400101

出版商:RSC    

年代:1977

数据来源: RSC

摘要:

102 REPORTS OF MEETINGS Proc. Analyt. Div. Chem. SOC. Reports of Meetings Western Region The twenty-second Annual General Meeting of the Region was held a t 6 p.m. on Friday, Jan- uary 21st, 1977, in the School of Chemistry, The University, Bristol. The Chair was taken by the Chairman of the Region, Mr. G. J. Dickes. The following office bearers were elected for the forthcoming year : Chairman-Mr. G.J. Dickes. Vice-Chairman-Mr. M. C. Finniear. Honorary Secretary-Dr. G. Nickless, School of Chemistry, The University, Bristol, BS8 1TS. Honorary Treasurer-Dr. D. Betteridge. Members of Comvnittee-Dr. E. J. Bradfield, Mr. C. F. Day, Mr. J . Gareth-Jones, Mr. F. R. Sweeting, Dr. J. D. R. Thomas and Dr. W. J. Williams. Mr. E. A. Hontoir and Mr. E. Minshall were re- appointed as Honorary Auditors.South East Region The second Annual General Meeting of the Region was held a t 6 p.m. on Tuesday, January 25th, 1977, at the Linnean Society, Burlington House, London, W.l. The Chair was taken by the Chairman of the Region, Mr. W. H. C. Shaw. The following office bearers were elected for the forthcoming year: Chairman-Mr. W. H. C. Shaw. Vice-Chairman-Mr. R. Goulden. Hon- orary Secretary-Dr. J . Warren, Laboratory of the Government Chemist, Cornwall House, Stamford Street, London, SE1 9NQ. Honorary Treasurer-Mr. D. W. Houghton. Members of Committee-Dr. A. H. Andrews, Dr. P. B. Baker, Dr. H. J. M. Bowen, Dr. S. J. Lyle and Mr. R. Sawyer. Dr. J. E. Page and Mr. D. C. M. Squirrel1 were re-appointed as Honorary Aud- itors.

ISSN:0306-1396    

DOI:10.1039/AD9771400102

出版商:RSC    

年代:1977

数据来源: RSC

摘要:

May, 19 7 7 USE OF ENZYMES IN ANALYTICAL CHEMISTRY 103 Use of Enzymes in Analytical Chemistry The following are summaries of three of the papers presented at a Meeting of the Analytical Division, organised by the Automatic Methods and Electroanalytical Groups, held on Decem- ber 8th, 1976, in London. Enzyme lmmunoassay S. A. Barker Chemistry Department, University of Birmingham, P.O. Box 363, Birmingham, B15 2TT Enzyme immunoassay is an assay applicable to a wide range of naturally occurring macro- molecules that can act as antigens, as well as small metabolites, drugs, and antibiotics that can function as haptens when attached to a carrier antigen such as albumin.The assay depends on the formation of a complex between the above antigens or haptens and their specifically interacting antibodies present as sera, purified immunoglobulins or even a compon- ent thereof.As an immunoglobulin is a protein and can itself act as an antigen, it is equally applicable to the assay of immunoglobulins. The function of the enzyme is to act as a catalytic label to monitor the interaction between the antigen and the antibody and in general it is covalently bound to either the antigen, hapten or antibody, any of which can be assayed by introducing into the mixture the unlabelled version of the molecule to be assayed either to act in competition with the labelled molecule or to be used sequentially in a non-competitive role.The assay can be performed with all of the components as a homogeneous mixture, or the antibody, antigen or hapten component can be immobilised on asolid phase.Alternatively, the components of an interacting mixture of soluble constituents can be fractionated into antibody- bound and free components by addition of an immunosorbent or precipitant. In many respects, the technique is therefore analogous to radioimmunoassay, which has constituted a growth area of clinical chemistry over the last decade in that it was tackling the assay at nanogram and picogram levels of the complex macromolecules, drugs and metabolites not accessible to a combination of mass spectroscopy and gas-phase chromatography or classical autoanalytical procedures.Enzyme immunoassay, however, has the great advantage that it can be performed with conventional spectrophotometers or fluorimeters.Stable, purified enzymes are now freely available and the sensitivity of assay has already reached that of measuring the enzyme content of a single cell for certain enzymes with fluorimetric substrates. This approach is also becoming more widely applicable elsewhere in clinical diagnosis as the histochemists have used enzyme-labelled antibodies to locate antigenic constituents of cells for a number of years.The following procedures summarise the currently available methods of enzyme immuno- assay. 1. Enzyme-linked immunosorbent assay (EL1SA)l uses an antigen covalently coupled to an enzyme label and the soluble conjugate so produced acts in direct competition with free antigen for sites of an interacting antibody immobilised on a solid support. The amount of enzyme activity in the immobilised support reflects the amount of free antigen present.One early application was the assay of IgG (rabbit), using its interaction with sheep anti-rabbit IgG immobilised on cellulose and alkaline phosphatase as a marker enzyme. In an alternative version,2 antigen binds to immobilised antibody and then antigen - enzyme conjugate is added sequentially.The loss of enzyme activity from the supernatant reflects the amount of free antigen present. HCG was used as the antigen and rabbit anti- bodies against it were coupled to cellulose. Peroxidase was attached as a marker to the HCG. 3. Thus, soluble antibody is mixed with soluble antigen and, after an interval, antigen - enzyme conjugate is added. The mixture is then fractionated by using a double antibody solid phase (DASP), which binds free antibody and antibodylantigen - enzyme conjugate.This technique enables free antigen - enzyme conjugate in solution to be assayed as a reflection of the amount of free antigen present. 2. A more sensitive procedure2 is to carry out the initial steps in solution.104 USE OF ENZYMES IN ANALYTICAL CHEMISTRY Proc.AnaZyt. Div. Chem. SOC. 4. The same procedure can be repeated using a soluble second antibody3 to precipitate first antibody and first antibodylantigen - enzyme complex instead of DASP. The enzyme activity recovered in the precipitate is inversely related to the amount of antigen in the sample. Analogous fractionation can be achieved with polyethylene glyc01.~ Immobilised antigen added to a mixture of soluble antigen and soluble enzyme-labelled antibody will absorb excess of free enzyme-labelled antibody so that the enzyme activity of the supernatant can be used to measure antigen present.6. Enzyme-labelled antibody can also be used in a sandwich5 type of enzyme immuno- assay. Immobilised antibody is first made to react with antigen so that the antibody is in excess.Enzyme-labelled antibody is then added to the washed immunosorbent whose activity is thereafter monitored. Pure enzyme-labelled antibody is not essential in this pro- cedure and all manipulations can be performed in a single tube. However, such an approach requires a soluble antigen with at least two antibody-combining sites. Another version6 of this sandwich assay is one in which the antigen to be assayed is incubated with excessive amounts of the enzyme-labelled antibody, followed by the addition of insolubilised antigen to remove the unreacted complex.The enzyme activity of the super- natant is then determined and it is possible in one such assay to detect 1.4 fmol (0.1 ng) of human ct-fetoprotein. This assay is similar to No. 6 but the antigen here7 is IgG (e.g., human) and it is interac- ted with immobilised second antibody such as rabbit (anti-human IgG) IgG.Subsequent incubation with rabbit (anti-human IgG) IgG - enzyme or the corresponding Fab’ - enzyme complex is followed by assay of the enzyme activity bound to the washed immunosorbent. In this way it is possible to determine as little as 0.3 fmol of human IgG if the marker enzyme /3-galactosidase is assayed fluorimetrically.An exciting new enzyme immunoassays operating in a sandwich fashion but not requir- ing a covalently bound enzyme conjugate is the competitive enzyme-linked immunoassay (CELIA). Binding of antibody to immobilised antigen is competitively inhibited by the free antigen to be measured. The amount of first antibody bound is determined by a technique in which a heterologous bridging antibody and a soluble antibody/enzyme complex are applied in sequence.Because higher ratios of enzyme to the first immunosorbent/antigen/antibody complex may be formed, CELIA offers the potential for greater sensitivity than the other en- zyme immuno-methods. The simplest and best established method is the enzyme multiplied immunoassay technique (EMIT).g A competition is set up between the small molecule to be assayed and the same molecule used as a hapten - enzyme conjugate for the binding sites on the antibody raised against hapten - albumin.The antibody complex with hapten - enzyme is inactive enzymically whereas free hapten - enzyme is active. Therefore, by enzyme assay the amount of free hapten in the sample can be determined. This type of assay is unfortunately confined to the assay of small molecules. 5.7. 8. 9. 10. References 1. 2. 3. 4. 5. 6. 7. 8. 9. Engvall, E., and Perlmann, P., Immunochemistry, 1971, 8, 871. Van Weeman, B. K., and Schuurs, A. H. W. M., FEBSLett., 1971,15,232. Belanger, L., Harnel, D., Dufour, D., and Pouliot. M., Clin. Chem., 1976, 22, 198.Cheung, M. C., and Slaunwhite, W. R., Clin. Chem., 1976, 22, 299. Maiolini, R., and Masseyeff, R., J . Immunol. Methods, 1975, 8, 223. Maiolini, R., Ferrua, B., and Masseyeff, R., J . Immunol. Methods, 1975, 6, 355. Kato, K., Fukui, H., Hamaguchi, Y.. and Ishikaura, E., J . Immunol., 1976, 116, 1554. Yorde, D. E., Sasse, E. A., Wang, T. Y., Hussa, R. O., and Garancis, J.C., Clin. Chem., 1976, 22, Scharpe, S. L., Cooreman, W. M., Blomme, W. J., and Laekeman, G. M., Clin. Chem., 1976, 22, 733. 1372. Enzymes in Analysis: Flow Microcalorimetric Aspects Anthony E. Beezer Chemistvy Department, Chelsea College, University of London, Manresa Road, London, S W3 6LX For many years the use of calorimetry in analysis has been commonp1ace.l It is, however, only recently that the availability of sensitive commercial microcalorimeters has permittedMay, 1977 USE OF ENZYMES I N ANALYTICAL CHEMISTRY 105 exploration of biochemical and microbiological applications of microcalorimetry in analysis.The flow microcalorimeter that has been most widely used in these applications is the LKB Flow Microcalorimeter (LKB Produkter, Bromma, Sweden, Type 10700-1) as de- signed by Monk and Wadso.2 This calorimeter, of the heat leak type, contains two operational calorimetric cells.In one, the mixing cell, two reagents enter separately, are mixed rapidly and then flow to waste. In the other, the flow-through cell, a reacting mixture is pumped through the cell; this mixture then either goes to waste or is returned to the original reaction vessel.The instrument measures the rate of heat generated within the selected cell by the reaction process relative to heat changes in the other (empty) cell as a reference. By this method the effects of unwanted thermal flows within the instrument are minimised. The operational conditions, procedures and the equations describing the response of the instrument have been reported previ~usly.~ These equations are shown (Table I) to involve kinetic as well as thermodynamic parameters ; the development was extended to include discussions of enzyme reactions.TABLE I RESPONSE OF CALORIMETER Reactions Mixing cell Flow-through cell Slow Fast -R2Ci(AHR + AHD,) - Zero order - (koVcAHx + B,C",hHD,) - ~OVCAHR First order -RR,C,"{AH~, + A H R [ ~ - exp(-hk17)]} -RR,C,"AH~[l - exp(-hK,.r)]exp(-kk,t) where R, is the flow-rate of the minor component; Ci $he concentration of the minor component ; AHR the heat of the reaction; AHD, the heat of dilution of component 2 in the solvent system used; ko the zero-order rate constant; Vc the internal volume of the calorimetric cell; k , the first-order rate constant; T the residence time of the reacting solution within the calorimetric cell; t the time from initiation of the reaction. The formal development of the response of the microcalorimeter to reactions of different kinetic order shows that both zero- and first-order reactions are accessible (this work has been discussed in more detail elsewhere as has the extension to reactions of different kinetic orders).4 These are the two limiting situations required for the determination of enzyme activity and substrate concentration, respectively.In this context, therefore, the microcalorimeter is simply another detector to be compared with extant methodologies. It does, however, have several distinct advantages over the more commonly used spectrophotometric procedures. These advantages are, principally, that the microcalorimeter is a non-destructive detector and makes no demand upon the system save that a reaction takes place.Thus there is no need for optical clarity, freedom from suspended matter, etc. The utility of the microcalorimetric technique in enzyme assay systems is not, in general, to be found in sensitivity. In this respect spectrophotometric procedures are probably more useful but they do have a special and in some instances limiting condition that either the substrate or product should contain a chromophoric group.The calorimeter with its sole requirement of a reaction of "sufficient" heat is therefore more general in application. Assuming a heat of reaction of approximately 36 k J mol-l it has been calculated3 that approxi- mately 1 pmol of reagent is adequate for assay purposes.A full discussion of the sensitivity of the microcalorimetric technique in enzymic systems has been given6 and it was shown that for substrate assays when substrate concentration [S] < Km, the Michaelis constant, These arguments have been advanced el~ewhere.~ ( I is the instrument response under these conditions and I , is the instrument response under zero-order conditions, ie., when [S] > Km).Thus the instrument response may be small in106 USE OF ENZYMES IN ANALYTICAL CHEMISTRY Proc. AnaZyt. Div. Chenz. soc. substrate analyses unless I , (effectively the enzyme activity) can be increased. Km, however, determines the practicable range of substrate concentrations that can be determined but does not affect the sensitivity of the procedure.Spink and Wadso have reviewed the applications of flow microcalorimetry in biological systems5 and refer to investigations on blood, tissues, cells, soil, serum, etc. Not surprisingly there are also references in the literature to the use of immobilised enzymes in this flowing system.’ These applications are not reviewed here but are mentioned in order to indicate the range of direct assay procedures which do not require prior separation of the active component.One of the most exciting prospects in biological assay procedures that are dependent upon enzymes is that of the use of micro-organisms. In the presence of excess of substrate, e.g., glucose, the reaction between organisms and substrate resembles a zero-order enzyme reaction.Moreover the calorimetric response is proportional to enzyme activity, as has been shown above, and thus to the “active” cell population. This procedure for counting cells has been used as a basis for a rapid diagnosis of bacteriuria.* Just as inhibitors can be analysed by their effect on enzymic activity so too can inhibitors of micro-organisms, i.e., antibiotics.The antifungal antibiotic nystating (and other polyene antibioticslO) has been assayed by its inhibition of respiration in Saccharomyces cerevisiae. The assay proved superior in sensitivity, reproducibility and speed of assay to the conventional agar plate diffusion. Furthermore, if the organism is presented with a complex growth medium the thermogram resulting from its growth and metabolic activity will be due to the heats associated with the complex enzymic reactions by which medium constituents are transformed into new cells, cellular material and products.Such identification procedures have been proposed,ll but doubts about the unique identification under certain circumstances have been expressed.12 In summary, microcalorimetric aspects of enzymic assay embrace all the principles outlined for other methodological approaches except that the procedure makes no special demands for particular functional changes in the system.Its advantage, therefore, lies in the ability of the calorimeter to accept as suitable assay material anything which can be passed through the pump and flow lines. Finally, inherent in all flowing systems is the possibility of automation.1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. References Tyrrell, H. J. V., and Beezer. A. E.. “Thermometric Titrimetry,” Chapman and Hall, London, 1968. Monk, P., and Wadso, I., Acta Chem. Scand., 1969, 23, 29. Beezer, A. E., and Tyrrell, H. J . V., Sci. Tools, 1972, 19, 13. Beezer, A. E., Biochem. SOC. Trans., 1976, 4, 570. Spink, C., and Wadso, I., in Glick, D., Editor, “Methods of Biochemical Analysis,” Wiley-Interscience, Beezer, A.E., Steenson, T. I., and Tyrrell, H. J. V., Talanta, 1974, 21, 467. Johansson, A., in Peeters, H., Editor, “Protides of the Biological Fluids,” Volume 20, Pergamon Press, Beezer, A. E., Bettelheim, K. A., Newell. R. D., and Stevens, J., Sci. Tools, 1974, 21, 13. Beezer, A. E., Newell, R.D., and Tyrrell, H. J. V., AnaZyt. Chem., 1977, 49, 34. Beezer, A. E., Newell, R. D., Chowdhry, B. Z., and Tyrrell, H. J. V., in the press. Russell, W. J., Farling, S. R., Blanchard, G. C., and Boling, E. A., in Schleninger, D., Editor, “Micro- Beezer, A. E., in Lamprecht, I., and Schaarschmidt, B., Editors, “Application of Calorimetry in Life New York, 1976. Oxford, 1972. biology-1975,’’ American Society of Microbiology, Washington, DC, 1975.Sciences,” de Gruyter, Berlin, 1977. Some Aspects of Utilisation of a Penicillin-sensitive Enzyme Electrode in Fermentation Control Sven-Olof Enfors Department of Technical Microbiology, Chemical Centre, University of Lund, P.O. Box 740, S-220 07 Lund 7, Sweden A penicillin-sensitive enzyme electrode was constructed from a pH (glass) electrode that was covered with /?-lactamase on the sensitive surface.The enzyme was kept on this surface by entrapping it with a dialysis membrane. The enzyme was either dissolved in a phosphate buffer or insolubilised on Sephadex, the Sephadex-bound enzyme being suspended in phosphateMay, 1977 USE OF ENZYMES I N ANALYTICAL CHEMISTRY 107 buffer. When penicillin diffuses into the enzyme, a local decrease in pH on the pH electrode will result from the enzymatic splitting of the /3-lactam ring, and the difference between this pH of the enzyme-covered electrode and the pH of the sample is referred to as the response of the penicillin electrode (ApH).Of particular interest are the problems of using an enzyme electrode in fermentation control.The glass electrode and all other components except the enzyme can be autoclaved and the enzyme is then introduced into the electrode under aseptic conditions. This design also offers a solution to another problem connected with the application of enzyme electrodes in fermentation control: the electrode can be used during a longer period than that limited by the inactiva- tion of the enzyme because it can be re-charged during operation.When the electrode was used daily for discrete sample analysis at room temperature, and kept in a phosphate buffer at room temperature between the measurements, the lifetime of one enzyme charge was 1-2d with dissolved enzyme and more than 2 weeks with Sephadex-bound enzyme. A third problem connected with the insertion of an enzyme electrode into the fermenter is the requirement for operation in untreated samples.This means, for instance, that the electrode must operate at high penicillin concentrations. This demand is partly fulfilled by the elec- trode as it gives an almost linear response to increasing concentrations of penicillin up to 15-25 mM, while a batch culture of Penicillium chrysogenum may yield up to 40-50 m M peni- cillin.Further, the electrode ought to be calibrated in advance as no standard additions can be made to the fermenter. A typical response time is 1 min, and is mainly determined by the thickness of the enzyme layer. The shortest response time (20 s) was achieved with a very thin film of dissolved enzyme between the dialysis membrane and the glass electrode. When Sephadex-bound enzyme is used, the response time is increased to a few minutes, the exact time depending on the amount and the size of the particles. Further, the response time increases when un- buffered or very weakly buffered samples are analysed.As the responses in buffered media are approximately linear, the sensitivity of the electrode to penicillin can be calculated as the slope of the response curve (-ApH versus concentration in millimoles per litre).How- ever, the sensitivity depends very much on the buffer capacity (p) of the sample. The buffer capacities of microbial broths normally change during growth and this change is especially pronounced for the penicillin process, which makes it impossible to pre-calibrate the sensitivity of the electrode in uninoculated broth.Efforts were also made to determine the buffer capacity of the broth in samples taken from the fermenter and to calculate the sen- sitivity of the electrode at this buffer capacity, but this procedure was unsatisfactory as the sensitivity of the electrode could be different in different samples with identical buffer capaci- ties.This effect is due to the fact that the complex broth contains large buffering molecules (e.g., proteins), which influenced the determination of the buffer capacity but which did not penetrate the electrode membrane and hence did not influence the sensitivity of the electrode. Samples are withdrawn from the fermenter and filtered, then the electrode is immersed in the stirred sample and the response is read.The electrode is then calibrated by the addition of a known amount of penicillin, the response of which is used to calculate the sensitivity. This pro- cedure can be used as the response to increasing concentrations of penicillin was found to be linear. The linear response to increasing concentrations of penicillin was surprising as theoretically the response (-ApH) should be proportional to the logarithm of the pencillin concentration, according to the Nernst equation. This result has been observed by other workers, but it was shown in this investigation that the Nernstian response is valid only in unbuffered samples. As weak a buffer as 0.00025 M phosphate buffer gave a linear rather than a logarithmic response pattern. An explanation of the linear response pattern was found when the following functions were examined: -ApH/mM = f(pH), -ApH/mM = f(p) and p = f(pH). Evaluation of these functions led to the following conclusion: the sensitivity to penicillin increases with in- creasing concentration of penicillin as a consequence of the enzymic reaction, which leads to local reduction of the buffer capacity within the enzyme electrode. This increasing sen- sitivity balances the decreasing sensitivity that is predicted by the Nernst equation. Sterilisation was achieved by utilising a special design of the electrode. At present this last demand cannot be met. This value is typically 0.06 pH 1 mmol-1 in penicillin broth. At present the folIowing procedure is used for the analysis of penicillin broth.

ISSN:0306-1396    

DOI:10.1039/AD9771400103

出版商:RSC    

年代:1977

数据来源: RSC

摘要:

108 GAS CHROMATOGRAPHY IN THE OIL INDUSTRY Proc. AnaZyt. Div. Chem. SOC. Gas Chromatography in the Oil Industry The following are summaries of three of the papers presented at a Joint Meeting of the Chro- matography and Electrophoresis Group, the Scottish Region and the Chromatography Discussion Group held on November 30th, 1976, in Grangemouth. Heat Desorption of Vapour-trapping Tubes D.T. Coker Esso Europe Inc., Esso Research Centre, Abingdon, Oxfovdshire, OX13 6AE The exposure of men to vapours in the air they are breathing can be monitored by the use of vapour-trapping tubes worn close to the man’s mouth, through which air is drawn by a small personal sampling pump. These tubes must then be analysed in the laboratory for the type and amount of vapour trapped.The NIOSH (National Institute for Occupational Safety and Health) system developed in the USA uses standardised small glass tubes containing 100 mg of charcoal adsorbent. The contents of these tubes are analysed by solvent desorption followed by gas-chromatographic analysis of the extract. This system has several disadvantages: on the spot readings are not possible, the pre- analysis procedure is time consuming, toxic desorption solvents are used, the solvent peak interferes with the chromatogram, recovery is often incomplete and the tubes have a limited capacity and cannot be re-used.The solvent dilutes the extract, reducing the sensitivity that can be attained. The constraint on detection limit has resulted in the tube being designed to allow high sampling flow-rates, and this feature leads to inefficient breakthrough characteristics.The large mesh size of the particles (2040) gives low flow resistance but poor chromatographic retention and reducing the mesh size to 60-80 increases peak retention by a factor of 2.3. The wide bore tubing (4 mm) also gives low flow resistance but poor peak retention and reducing the bore to 2.5mm increases peak retention by a factor of 2.2.The small amount of adsorbent used (100 mg) also limits retention and capacity. Increasing the mass to 250 mg increases retention by a factor of 4.3. The most obvious way of overcoming these limitations is to use heat desorption from the tube directly into a gas chromatograph as this procedure has many potential advantages: no sample preparation is involved and no toxic solvents are used.There is no solvent peak on the chromatogram and no dilution of the sample by solvent. There is less restriction on tube design, so that tubes with greater capacity and longer breakthrough times can be made. Recovery is more complete and the tubes can be re-used. Equipment is commercially available for heat desorption, but from published literature it does not appear that the technique has yet been fully investigated and maximum benefits obtained. It has been said that the use of temperature programmed gas chromatographs appears to be essentia1.l This restriction would limit the use of the technique to laboratories with sophisticated gas chromatographs and extend the time required for the analysis.Our work has been directed toward understanding the basic characteristics of the technique and optimising the design of heater and tubes.A simple heater has now been developed that fits into a portable gas chromatograph and a range of three types of tube allows desorption directly on to an isothermal gas-chromatographic column. The system is easily fitted to any gas chromatograph.An investigation of the characteristics of the trapping tube in which the following parameters are being studied is nearly completed : desorption volumes (the volume of purge gas required to completely desorb the trapped vapour) are being determined for each type of tube and for compounds with different volatilities ; the effects of temperature, vapour concentration and humidity on breakthrough volume ; the desorption efficiencies of various compounds and also the loading capacity of adsorbents and the storage characteristics of the tubes.The knowledge of these factors can then be applied to the monitoring of particular vapours. The most suitable type of trapping tube and gas-chromatographic column can be selected so that the desorption volume can be matched to the gas chromatograph peak elution volume to minimise peak broadening and interference with neighbouring peaks.May, 1977 GAS CHROMATOGRAPHY IN THE OIL INDUSTRY 109 The breakthrough volume (the volume of air that can be drawn through the tube before the vapour breaks through the adsorbent bed) can also be estimated from the ambient temperature and the expected average level of vapour so that sample flow-rate and maximum sampling period can be defined.This system has been successfully used for several applications such as the determination of benzene in gasoline vapour from truck loading, vinyl chloride monomer during product- ion of poly(viny1 chloride), methyl chloride during rubber production, butadiene in butenes and butanes from steam cracker units, n-hexane in hexane solvent vapour, ethyl methyl ketone in de-waxing processes, and determination of several petroleum distillate vapours.For most applications the breakthrough volumes allow full-shift (8 h) sampling periods and the tubes can be analysed within a few minutes. Full details of the results of these investigations will be published when the work is finished.Reference 1 . Parkes, D. G., Gantz, C. R., Polinsky, A., and Schulze, J., Am. I n d . Hyg. Ass. J . , 1976, 37(3), 165. Sources of Error in Gas-chromatographic Analysis A. G. Butlin Shell Research Ltd., Thornton Research Centre, P.O. Box 1, Chester, CH1 3SH The early development and application of gas chromatography (GC) received much of its impetus from the petroleum industry. It was recognised as a technique that could readily provide more detailed analytical information about volatile complex mixtures than the old test methods.In process-control applications, GC is capable of high precision and accuracy for two reasons; first, the plant streams do not vary widely in composition, and secondly the methods are calibrated accurately with appropriate reference blends.The picture is completely different when GC is applied to the solution of problems associated with customer complaints or to trouble-shooting. The analyst often has to reconcile the pressures for a quick answer with financial constraints on the effort he can apply. There are then many factors that contribute to the uncertainty of the results determined and it is clearly important that the analyst should be aware of them so that he can assess their significance.Integrity of the Sample The sample may have been taken many miles away by a non-specialist unaware of the difficulties of representative sampling and the risks of contamination from a re-used container. Equally important are the conditions of storing or transporting the sample before it reaches the laboratory, and the way in which the analyst “samples the sample.’’ Again, the sample may be very small so that the analysis cannot be repeated.The sample may be degraded by pre-analysis treatments such as extraction and derivati- sation.lY2 The total recovery of sample components from the GC column has been shown to be dependent upon the sample volume inje~ted.~ Gehrke and Goerlitz4 studied the pre- cision of the determination of fatty acid esters and found high relative standard deviations for the lower members.Sample Introduction For liquid samples and solutions, microlitre syringes are in common use and have been discussed in detail by Grant and Clarke.5 Fractionation of a mixture can occur before, during or after injection and serious problems can arise with splitters on capillary columns. Splitters should always be tested with appropriate known blends before use in quantitative analysis.On- column injection seems to be better than flash evaporation for low- and medium-boiling mixtures but the reverse is true for wide-range mixtures. Detectors Only gases can be introduced on to the column in accurately known amounts.Concentration-dependent detectors (e.g., katharometers) require accurate control of tem- have shown that the response of perature, pressure and flow-rate.6 Recently, Novak et110 GAS CHROMATOGRAPHY IN THE OIL INDUSTRY Proc. Analyt. Div. Chem. SOC. a katharometer used with a temperature-programmed column requires correction according to the retention temperature of each component in addition to any response-factor corrections.Mass-flow detectors (e.g., flame-ionisation detectors) are not completely immune to changes in temperature and carrier gas fl~w-rates.~ They are affected by hydrogen and air flow-rates but these effects are well known.10 Electrometer Amplifiers These amplifiers are designed to give a voltage output proportional to a small current input.Most of those sold now are described as “wide-range” and will have a typical linear dynamic range of 1 : 106. Early models were generally of poor quality; one popular model saturated at 140% f.s.d. when connected to a recorder of appropriate range. Peaks had therefore to be kept “on-chart” to ensure that they were not flat-topped. The popularity of electronic integrators has forced manufacturers into the use of higher quality amplifiers.The amplifier response should be checked at intervals by feeding a small voltage from a variable calibrated source into the flying lead connector across a high resistance and measuring the output voltage with a digital voltmeter. The output voltage should vary linearly with the input millivoltage up to the rated maximum output.Saturation problems with ampli- fiers can pass unnoticed unless they are specially sought. Peak-area Measurement Peak-height measurements are not considered here because peak height, being affected by injection technique, is useful only when highly standardised injection methods are used, e g . , in automatic GC equipment. Manual methods are suitable for simple chromatograms and peak height x width at half-height is the best.Peak height x retention distance on the chart should be relied on only if the chart-drive speed has been shown to be uniform over peak-width times, say intervals of about 15 s.ll Grant and Clarke12 recommended the elec- tronic integrator as the best means of area measurement. Triangulation and planimeter methods are not very repeatable. Electronic Integrators Integrators are in general use for area measurements and cover a wide price range.An integrator should be chosen only after careful consideration of its specification in relation to the work required of it. The simplest integrators detect peak inception by a rise of the signal above a pre-set threshold level. Others make a logical decision from measurements of the rise above threshold level, slope of the signal and the time for which the change is maintained.However, the electronic integrator pro- vides no quick solution to problems of area measurement. The operator needs experience to obtain the best results from his integrator, particularly in the measurement of small peaks, where threshold levels and slope detection levels can alter the measured areas by factors of, say, two or three.The Dedicated Computer The dedicated computer demands yet further expertise in the operator but gives better facilities for the use of special programs (e.g., true boiling-point analysis), the allocation of names, application of correction factors, the editing of results and the output of results on cassette magnetic tape for use, perhaps, as input to a large computer.A disadvantage is that a skilled engineer is needed to repair a major breakdown and that the gas chromatographs will be useless unless a fall-back system is provided. Also, auto- matic running of gas chromatographs under computer control makes high demands on constancy of GC performance. This may be a hidden blessing if it results in an all-round improvement in manufacturers’ products.Leung et aZ.13 suggested that microprocessors attached to each chromatograph will displace the dedicated computer. This may be so in the long term but at present there is little sign that the alleged cheapness of microprocessors is reflected in the prices asked for chromato- graphs so equipped. It is more likely that the change will take place slowly over a long period because it will be governed by the rate at which existing equipment becomes due for replacement.Base-line correction is also possible.May, 1977 GAS CHROMATOGRAPHY IN THE OIL INDUSTRY 111 Peak-area Correction Factors Only saturated hydrocarbons can be regarded as giving a constant response with respect to carbon content on the flame-ionisation detector (FID).For the most accurate work with these compounds and for other classes of compounds, area correction factors must be cal- culated from results on known mixtures. Published factors are useful but different workers using different equipment can arrive at different values.l* The presence of water in a sample is often ignored because the FID does not respond to it.Foster and Murfin15 have shown that co-elution of water with a carbon compound results in a reduced response for that com- ponent. Normalisation or Internal Standard ? It can be a salutary experience to perform an analysis both with and without an internal standard, particularly if the sample has been subjected to chemical pre-treatment. A wide range of reference compounds are available but they should be checked for authenticity. Internal standards should always be used for non-routine work so as to prevent errors arising from the presence of material that will not elute from the column under the conditions used.Standard addition of a sample component is sometimes necessary for a complex mixture. Novak and Janakl6 have drawn attention to numerous pubIished calculation formulae that have serious errors.Conclusion An appreciation of these main sources of error in GC analysis will encourage the individual worker to derive a realistic measure of the precision of his final results. This is specially important in investigational work where there is no known “right answer.” Results often have to be communicated for use by a third party and this argument is even more compelling so that no unwarranted inferences are drawn.There is a very good case for involving the analyst with a problem from the start, rather than calling him in at the end. 1 . 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. References Koritala, S., and Rohwedder, W. K., Lipids, 1972, 7, 274. Solomon, H. I., Hubbard, W.D., Prosser, A. R., and Sheppard, A. J . , J. A m . Oil Chem. SOC., 1974, 51, Seino, H., Watanabe, S., Nihongi, T., and Nagai, T., J . Am. Oil Chem. Soc., 1973, 50, 335. Gehrke, C. W., and Goerlitz, D. F., Analyt. Chem., 1963, 35, 76. Grant, D. W., and Clarke, A., J. Chromat., 1974, 97, 115. Walker, J . Q., Jackson, M. T., Jr., and Maynard, J . B., “Chromatographic Systems,” Academic Press, Novak, J., Guha, 0.K., and Janak, J., J. Chromat., 1975, 112, 365. Novak, J . , Guha, 0. K., and Janak, J., J . Chromat., 1976, 123, 497. Gill, J . M., and Hartman, C. H., J. Gas Chromat., 1967, 5, 605. McWilliam, I. G., J. Chromat., 1970, 51, 391. Girling, G. W., Gigg, A. R., and Heley, M. R., J. Chromat., 1967, 31, 525. Grant, D. W., and Clarke, A., J. Chromat., 1974, 92, 257.Leung, A. T., Rock, J . V., Henry, R. A., Derge, K., and McIllwrick, R., J. Chvomat., 1976, 122, 355. McTaggart, N. G., and Mortimer, J. V., J . Inst. Pet., 1964, 50, 255. Foster, J . S., and Murfin, J. W., Analyst, 1965, 90, 118. Novak, J., and Janak, J., J. Chromat., 1967, 28, 392. 424. New York, 1972, p. 152. Some Aspects of Gas Chromatography in Petroleum Prospecting A.G. Douglas Organic Geochemistry Unit, Drummond Building, Geology Department, The University, Newcastle upon Tyne, NE1 7RU Most of the world’s reserves of petroleum and natural gas are confined to sedimentary basins. In these basins, organic matter from marine and continental sources has accumulated and, with increasing burial, undergone physical and chemical changes which may result in oil or gas accumulations.The organic geochemist is interested in understanding these changes so that he can subsequently predict, regionally and stratigraphically, where oil may occur.112 ANALYTICAL ATOMIC SPECTROSCOPY Proc. Analyt. Div. Chew. SOC. Important factors for oil occurrence include the nature and amount of sedimentary organic matter and the depth to which it has been buried or the temperature to which it has been subjected.With increasing burial, changes in the amount and distribution of hydrocarbons are also used as diagenetic indicators. In basins where there is some contribution from terrestrial organic matter, normal alkanes lose their high odd carbon number predominance, their distribution changes from higher to lower relative molecular masses and their proportion of the total organic carbon increases.Cycloalkane patterns change so that there is a depletion in steranes and triterpanes and there is frequently an increase in some acyclic isoprenoid hydrocarbons. A more detailed investigation of the triterpanes indicates that the rate of disappearance of certain types, with burial, is dependent on their stereochemistry. For instance, the C,, triterpane 17P-H-trisnorhopane disappears earlier in the maturing sediment than does the more stable 17a-H isomer; a similar preferential disappearance of the 17P-H- norhopane with respect to the 17a-H isomer is also apparent. Direct analyses of hydrocarbon gases may determine whether the organic matter is imma- ture, or whether it has oil potential; this potential may also be judged by measuring the ratios of volatile, residual and total carbon in laboratory-heated samples. Many of these measurements may also indicate if a state of thermal alteration has been reached at which dry or wet gas can be expected. Another important aspect of these studies is to determine whether changes undergone by organic matter during burial can be simulated in the laboratory. Results of heating recent sediments, sedimentary extracts and other kerogens during which hydrocarbons are pro- duced, help to answer these questions in part. Analyses by packed-column and capillary- column gas chromatography are used to exemplify many of the changes discussed.

ISSN:0306-1396    

DOI:10.1039/AD9771400108

出版商:RSC    

年代:1977

数据来源: RSC

摘要:

112 ANALYTICAL ATOMIC SPECTROSCOPY Proc. Analyt. Div. Chew. SOC. Fourth Annual Reports on Analytical Atomic Spectroscopy Symposium The following is a summary of one of the papers presented at the Symposium organised by the Atomic Spectroscopy Group, the Board of the Annual Reports on Analytical Atomic Spectro- scopy and the Modern Methods of Analysis Group of the Sheffield Metallurgical and Engineering Association, held on January 6th, 1977, at the University of Sheffield.Development of a Dedicated Atomic-absorption Spectrometer for the Determination of Elements that Form Volatile Hydrides J. R. S. Broughton and C. W. Fuller Tioxide International Limited, Stockton-on-Tees, Cleveland, TS18 2NQ The determination of arsenic and other elements that form volatile hydrides by means of atomic-absorption spectrometry has become popular in the last 5 years. However, little work has been described on industrial applications of this technique.Most workers have used a hydrogen diffusion flame or a flame-heated silica tube for decomposition of the covalent hydrides. The use of a heated silica tube has a number of advantages; in particular, it provides a more stable atomisation environment and a long absorption path, thus increasing reproducibility and sensitivity.It is difficult to obtain uniform heating of a silica tube by use of a flame1 and additionally the top of the tube will be cooler than the directly heated underside. Vijan and Wood2 developed an automated method for the determination of arsenic in atmospheric particulate matter, using the hydride method and an electrically heated silica tube for decomposition of the evolved arsine.Their silica tube was wound with heating wire. This method has been found to have the disadvantage that when the silica tube required replacement the complete wire-wound tube had to be replaced. A more convenient technique, for industrial applications, was considered to be the use of a small electrically heated tube furnace, which would allow rapid replacement of the silica tube independently from the heating system.May, 1977 ANALYTICAL ATOMIC SPECTROSCOPY 113 Instrument Development Two semicircular ceramic holders (100 x 15 mm i.d.), each containing four heating ele- ments running longitudinally and connected in series, were used as the heater.A semi- circular hole (10 mm diameter) was also cut from the centre of one side of each of the holders to allow a cylindrical T-shaped silica atomisation cell to be fitted (Fig, 1). The holders con- taining this T-shaped tube were mounted in two shaped firebricks, which were bolted together. The complete furnace assembly was supported on a jack, which replaced the burner assembly in the original atomic-absorption spectrometer, so that both vertical and horizontal adjust- ments could be made.The heating elements were connected to the mains supply via a variable transformer mounted in the chassis of the instrument. The atomic-absorption spectrometer used in this work was a Shandon Southern A3000 with the burner assembly removed. The four-lamp turret holder was replaced by a single adjust- able cradle holder for the hollow-cathode lamp.The front centre and right-hand control panels were replaced by a specially designed single panel. This panel contained the rota- meter and controls for slit width, lamp current, furnace position and transformer together with the hydride generation cell. Standard hydride generating conditions, using sodium borohydride, were used for the investigations described here.l The operating conditions for the elements arsenic, bismuth, antimony, selenium and tellurium were then optimised.It was found that 82 V supplied from the transformer (corresponding to 850 "C in the hottest part of the silica tube, with a nitrogen carrier gas flow-rate of 1.6 1 min-l) was sufficient for maximum absorption signals of all the elements.a b a Fig. 1. Electrically heated tube furnace: (a) heating elements, (b) silica tube, (c) cooling nitrogen and (d) hydrides and nitrogen carrier gas. Interference Effects When considering applications of the hydride generation technique to the particular problems of a manufacturer of titanium(1V) oxide pigments [ e g . , the analysis of ilmenite, titanium( IV) chloride and titanium(1V) oxide] the main consideration must be the possible interference effects of titanium and iron.Trace amounts of cobalt, chromium, copper and nickel are also present and these four elements together with iron are among the elements reported by Smith3 to suppress severely the signals for arsenic, bismuth, antimony, selenium and tellurium when using a hydrogen diffusion flame.The effects of 0-10 000 pg ml-1 of iron(II1) and titanium(1V) oxide and 0-1 000 pg ml-1 of cobalt(II), chromhm(VI), copper(I1) and nickel(I1) on 0.2 pg ml-l of arsenic, bismuth, antimony, selenium and tellurium were, therefore, investigated (Fig. 2). For the applications considered here, only selenium would be affected by titanium(1V) oxide and even at 10 000 pg ml-1 the selenium signal is still sufficiently strong to allow this element to be determined by the standard additions procedure. For the other transition elements investigated, the levels present in the materials to be analysed, after dissolution and dilution, were not sufficient to interfere with any of the determinations.114 ANALYTICAL ATOMIC SPECTROSCOPY Proc.Analyt. Div. Chem. Soc. Q) 0 (IJ e . n w , a - i j ; l 0, 2 0 10 100 1000 10000 Concentration of TiOPIpg ml-' 11 (6) Bi AS Sb Se Te // I I I I :;-"o Q 0 100 1000 Concentration of Co(l I )/pg mI-' 100 1000 Concentration of Cu( I I )/pg mi-' B a EEZl 0 10 100 1000 Te Concentration of Cr(VI)/pg m1-I I I 0 100 1000 Concentration of Ni(ll)/pg ml-' Fig. 2. Effect on the determination of arsenic, bismuth, antimony, selenium and tellurium, each at 0.2 pgml-l, of (a) Ti(1V) oxide, (b) Fe(III), (G) Co(II), (d) Cr(VI), (e) Cu(I1) and (f) Ni(I1).Applications of the Hydride Generation Technique Perhaps the greatest problem in the analysis of ilmenite and titanium(1V) oxide pigments for arsenic, bismuth, antimony, selenium and tellurium is the dissolution of the matrices at a sufficiently low temperature so that the elements are not lost by volatilisation. Although individual techniques are available for dissolution of the matrices with a minimum of loss of each of the impurities it was intended that a single procedure should be used which would enable all of theimpurities to be determinedin the one solution.Sodium peroxide disintegrates both ilmenite and titanium(1V) oxide into a mass that is easily attacked by acids and should also convert the elements to their higher oxidation states.By using the standard additions technique, recoveries greater than 80% were obtained after sintering the mixture with sodium peroxide at 600 "C for arsenic, bismuth and selenium; however, less than 5% of the added antimony and tellurium was recovered. Sintering at 500 "C gave good recoveries for arsenic, bismuth, antimony and selenium and at 400 "C all of the elements were recovered in amounts greater than 95%.The proposed method, therefore, involved sintering 1 g of finely ground ilmenite or pigment with 17 g of sodium peroxide for 1 h in a muffle furnace at 400 "C. The mass was allowed to cool and was then disintegrated with dilute tartaric acid. An aliquot of the solution wasMay, 1977 EMERGENCY PROCEDURES FOR A CHEMICAL LABORATORY 115 further acidified with hydrochloric acid and diluted. Arsenic, bismuth, antimony, selenium and tellurium were then determined by the atomic-absorption spectrometry - hydride generation technique. Titanium( IV) chloride was analysed directly after hydrolysis with ice-cold hydrogen peroxide in a closed system followed by acidification. References 1. 2. 3. Thompson, K. C., and Thomerson, D. R., Analyst, 1974, 99, 595. Vijan, P. N., and Wood, G. R., Atom. Absorption Newsl., 1974, 13, 33. Smith, A. E., Analyst, 1975, 100, 300.

ISSN:0306-1396    

DOI:10.1039/AD9771400112

出版商:RSC    

年代:1977

数据来源: RSC

摘要:

May, 1977 EMERGENCY PROCEDURES FOR A CHEMICAL LABORATORY 115 SAFETY IN ANALYTICAL LABORATORIES Preparing Emergency Procedures for a Chemical Laboratory Many types of emergency can occur in labora- tories, including, of course, those concerned with analytical work. All emergencies require imme- diate action and one cannot stress too highly the importance of all personnel being familiar with and trained in the correct procedure to follow at such times.As it is impossible to give specific instructions to cover all contingencies in every type of laboratory, the aim of this article is to point out the types of emergency which should be covered and to suggest various means of achieving good, safe working procedures. Fire Fire is probably the most common emergency with which staff or students will have to deal.The local Fire Authority will advise on the number of fire alarms that ought to be fitted and their suitability. These alarms should be tested regularly to ascertain that they are clearly audible in the area that might be affected and in the immediate vicinity. Staff and stu- dents must be aware of their locations and mode of operation.A small, pre-printed label, with the telephone numbers required to summon the Fire Services and ambulance/medical assistance, fixed to each telephone is a useful aid. Fire doors in corridors should be clearly marked as such and the message instilled that they must not be left open as their purpose is the prevention of the spread of fire and smoke. Electrically operated doors, triggered by the fire alarm, are an improvement on the normal fire door.They can be set to be held open until the fire alarm is activated, when they immedi- ately close. Whenever possible, keep doors between laboratories closed, as well as those which open from the laboratory into a corridor. Close doors and windows in laboratories not in use and at the end of the working day. Clearly signpost fire escape routes, which, together with fire exit doors, must be kept un- obstructed, and give all personnel instructions on the correct procedure for evacuation in case of fire.Particular emphasis should be made that lifts must not be used as a means of exit. Give clear instructions on the location of assembly points. A notice, giving the instruc- tions for the procedure in case of fire, posted in each room is a useful adjunct, particularly for the benefit of visitors.Regular fire drills in- volving evacuation of buildings are recom- mended as any de4ciencies will be highlighted. In small concerns, it may be suitable to have a roll call, but where large numbers of persons may be involved this is inadvisable. It could take an excessive length of time to complete because it is unlikely that the location of every- one will be known at any one time.An alterna- tive is to appoint wardens or stewards whose duty is to supervise the evacuation and check that all rooms, including cloakrooms and toilets, are empty. It is a considerable advantage if all personnel are trained in the use of the various types of fire extinguishers that are available on the premises.As a minimum they should be informed of their location, operation, mechan- ism, extinguishing effect, characteristics and cir- cumstances under which they should be used. Fires involving electrical equipment and those involving a person whose clothing is on fire require particular attention.116 EMERGENCY PROCEDURES FOR A CHEMICAL LABORATORY Proc.Analyt. Div. Chem. SOC. When compiling fire procedures, account should be taken of the various hazards connec- ted with gas cylinders. There is the danger associated with the gas cylinder becoming over- heated through being involved in a fire, or that of a leak, from a cylinder of flammable gas, igniting. A useful “Code of Practice for the Use of Gas Cylinders in Analytical Laboratories” was published in the March issue of Pvoceedilzgs (p.57) as the first of these articles on safety. Fires involving materials that, when decom- posed, emit toxic fumes must be considered and the appropriate instruction given on the wearing of breathing apparatus while extinguishing such a fire. Finally, it must be stressed that, if an extinguisher is partially used, or emptied, it should be replaced immediately with a full one.An empty extinguisher is worse than none a t all as it gives a false sense of security. Some can leak and a regular check by weighing is recom- mended. Accident Facilities for the treatment of accidents can vary extensively from one concern to another. They can extend from a person trained in first aid to the type of medical centre that is, in effect, a miniature hospital with a doctor and nursing staff in attendance.The extent of the treatment facilities has no bearing on the fact that all accidents, however minor, should be treated promptly and a record kept of the inci- dents. It is important to know the cause of the accident so that steps can be taken to pre- vent a recurrence. Simple first-aid measures, capable of quick application and of being administered by un- skilled hands, should be the basis of accident procedures.Further treatment should be given only by trained medical staff. The site of the ambulance room/dressing station or medical centre should be shown to all staff or students when they first join the Institute or Company, and the means by which they can summon expert help should be indicated clearly.Again, the telphone number to summon an ambulance or a doctor can be fixed to each telephone. A “personal” alarm with a distinctive sound can also be used. A list of persons, including their telephone numbers and locations, who are trained in first aid and hold first-aid certificates can be promin- ently displayed. Bottles containing eye-wash solution, clearly labelled and protected from contamination, should be available in every laboratory and re- placed regularly.Various types of eye-wash bottles are on the market and it is essential that everyone working in the laboratory is capable of carrying out an eye-wash procedure. Treat- ment for chemical splashes in the eye must be immediate to be effective.Some eye-wash bottles are designed for self-operation and before they can be used by one person on another the patient must be laid down. In all cases of eye injury skilled medical attention should be obtained. When setting out accident procedures, stress the fact that skilled attention, if available, should always be obtained for injuries, no matter how slight. Place clearly displayed first-aid boxes, containing sterile dressings, at convenient points.Treat all cuts, however slight, as they can develop into a more serious injury by ingress of a virus or toxic substance. Fit a drench shower in each laboratory, connected either to a cold-water tap or, if possible, a built-in unit that delivers tepid water. The first essential with a heat burn is to cool the affected part under running water. Do not apply anything other than water-leave other treatment to the experts. In cases of major burns, summon an ambulance immediate- ly and keep the patient warm and quiet until it arrives.Have available a clean blanket for use when shock is apparent. When preparing instructions for the treatment of burns caused by corrosive materials, point out the need for protection against self-injury. It may be necessary to remove contaminated clothing from the injured person and although this will be carried out while drenching with water there is always the danger of self-con- tamination.Similarly with skin contamination by toxic or flammable materials, it may be necessary to don protective clothing and/or a breathing set before approaching the patient.Emphasise that one patient is enough and, although the first reaction is to help the injured, others must stop and think before approaching. All protective clothing should be kept in good condition and be easily accessible. Give instruc- tion to at least some, but preferably all, per- sonnel, in the use of breathing sets or gas masks and stress that gas masks are not self-contained breathing sets but contain filters that only give protection against specific toxic materials according to the type of filter fitted.Only trained personnel should use a breathing set. An oxygen resuscitator, for the use of persons trained in first aid, is a useful addition to the first-aid equipment. Its use may be desirable in the case of unconsciousness.Mouth to mouth resuscitation is excellent if used in the correct circumstances but could cause seriousMay, 1977 EMERGENCY PROCEDURES FOR A CHEMICAL LABORATORY 117 self-injury if the patient has inhaled poisonous gas or swallowed a poison. Advise against the administration of antidotes for slow-acting poisons. This treatment should be left to the doctor or other trained medical staff - Extremely toxic fast-acting gases, such as hydrogen cyanide, are the exception, and a suitable antidote must be located near at hand to workers using the gas.They should be fully informed of the correct method of administra- tion. Give specific instructions when antidotes or special treatments may be administered with medical approval. Emetics should never be used. Instructions should be given on the danger of touching a person suffering from electric shock.Give the procedure to follow if he is in contact with a live conductor. Spillage of Chemicals To produce emergency procedures that would cover the spillage of all chemicals, under every circumstance in the laboratory, would be a mammoth task and in practice is impossible. Only guide-lines can be given as the final decision on the correct course of action is that of the person in charge of the laboratory.He should familiarise himself with the hazards related to the materials being used in his laboratory. Classification into “major” and “minor” spillages presents difficulties as it depends on the toxicity, flammability, etc., of the material involved. A small amount of liquid with a very low flash-point or low threshold limit value (TLV) could be classed as a major spillage, while the same amount of material with a high flash-point or high TLV would be classed as a minor spillage.Protective clothing (goggles, gloves of various types, PVC suits and boots) should be readily available and the necessary warnings given on the deterioration of rubber gloves that occurs when they are in contact with oxidising agents and some solvents.Take into account the toxicity, if any, of the chemicals spilled and wear the necessary protec- tive clothing. With toxic materials consider whether the toxicity, in this case taken to mean material with a very low TLV, is from the vapour only, whether the material is a skin irritant or sensitisor or can be absorbed through the skin.A useful criterion is that if the vapour pressure in millimetres of mercury a t 20 “C divided by the TLV in parts per million is greater than unity, breathing apparatus should be worn. Emnhasise the necessitv of wearing full eye protection, not safety glasses, when coping with spillages of corrosive materials. Specific instructions are essential for the handling of special chemicals such as carcinogens, benzene, phenol and mercury.With spillages involving toxic materials, the area should be cleared of everyone except the people involved in the cleaning up process, and the atmosphere should be monitored and declared safe before allowing anyone to re-enter. When issuing instructions, point out the danger of the ignition of flammable materials and advise that, if i t is possible and safe to do so, sources of ignition should be extinguished. If sufficient flammable material is spilled to form an air explosive mixture with the vapour, there is the added danger of an explosion occurring, Remind the staff of the possibility of flammable vapours travelling below or a t ground level and being ignited some distance away from the spillage.Some materials are flammable, corrosive and toxic. Small spillages of some flammable materials can be mopped up with absorbant paper, which can then be ignited, under controlled conditons, in a fume cupboard. Have available suitable absorbants for corrosive and flammable mater- ials. A covered container is useful for the removal of the contaminated absorbant from the laboratory.Issue instructions for dealing with contamin- ation of personnel (these should follow the same procedure as given for accidents), giving as the first essential the removal of the person from exposure and again stressing the need for protection against self-injury. Toxic Gas Emission In a laboratory, the accidental release of toxic gas into the atmosphere can occur if the fume- cupboard extraction system fails, from a leaking gas cylinder or from a spillage of toxic material. Any experiment involving the use of toxic gas, or where toxic gas may be evolved, should be carried out in an isolated fume cupboard, preferably with an independent extraction system.High-speed extraction systems fitted with a failure alarm should be used for highly toxic gases such as hydrogen cyanide, and personnel handling these gases must be specially trained for any emergency that might arise.It is advisable to monitor regularly the area immediately outside the fume cupboard where toxic gases are being handled, and a breathing set should be kept near at hand in case of emer- gency. To protect the extraction ducting and fan.when Dossible. use a suitable scrubbing118 FOURTH SAC CONFERENCE Proc. AnaZyt. Div. Chem. SOC. tower to absorb all corrosive fumes. Inspect the system frequently for signs of corrosion, as this can be the cause of low face velocities or sudden failure owing to collapse of the fan or fan housing. If toxic gas is released into the laboratory, evacuate it immediately and warn others in the vicinity.When instituting procedures for evac- uation, it is recommended that wardens or stewards, trained in the wearing of breathing sets, are appointed. They can then don the necessary protective clothing and, wearing pro- tection against inhalation, ascertain that the evacuation is complete, at the same time open- ing windows and any external doors to the laboratory and closing all internal doors. The laboratory should not be re-entered until the atmosphere has been monitored and declared safe. Conclusion In all establishments, it is imperative that emergency procedures are clearly understood by everyone. They should be agreed with the pertinent authorities, written in an unambiguous form and issued to all who may be involved. It is the management’s responsibility, possibly by the appointment of a Safety Officer, to ensure that there is no conflict in the basic instructions within their own establishment. Part of such a Safety Officer’s remit would be to ascertain that these instructions are at all t.imes valid, the necessary training is organised and records are maintained of any incidents. Finally, it must be remembered that the work programme influences the type of emergency that can arise and that any possible changes to the programme could affect the emergency pro- cedures.

ISSN:0306-1396    

DOI:10.1039/AD9771400115

出版商:RSC    

年代:1977

数据来源: RSC

摘要:

118 FOURTH SAC CONFERENCE Proc. AnaZyt. Div. Chem. Soc. Fourth SAC Conference July 17-22, 1977, Birmingham A comprehensive programme has been arranged for the Fourth SAC Conference, which is to be held at the University of Birmingham between July 17th and 22nd, 1977. Details are as follows. Plenary Lectures Monday, July 18th: Professor R. Belcher on The Resurgence of Analytical Chemistry. Tuesday, July 19th: Dr.I?. P. W . Scott on Highlights from Contemporary Chromatography. Thursday, July 21st: Professor Yu. A . Zolotov on Hybrid Methods of Analysis. Friday, July 22nd : Professor V. A . Fassel on X-ray Excited Optical Luminescence-Present Status and Prospects. Papers and Poster Sessions Monday, July 18th Some Problems of Accuracy and Precision in Trace Analysis and Low-level Radioactivity Measurements as Evidenced by Recent IAEA Intercomparison Runs.I?. Dybczynski, A . Tugsavul and 0. Suschny ( Vienna, Austria). Round Robin Studies for the Estimation of Accuracy and Precision of Environment Control Analysis. T. Fujirnovi, S . Araki, T. Yoshirnori, Y. Iida, Y. Urnezaki, E. Iwarnura, M. Kushiro and K. Ozasa (Tokyo, Japan). Comprehensive Quantitative Trace Element Analysis by Spark-source Mass Spectroscopy.A . M . Ure and J . R. Bacon (Aberdeen, U K ) . Analytical Problems Concerning Natural Water. Extraction of Plutonium(1V) and Thorium with Tridodecylamine from Nitric Acid Soil Leach Solutions. Study of the Relations between Biological, Physical and Chemical Water Quality Description with Pattern Recognition Techniques.B. G. M . Vandeginste .and P. Van Iersel (Nijmegen, The Netherlands). Extraction of Copper(II), Cobalt(I1) and Iron(II1) from Aqueous Thiocyanate Solutions into Propylene Carbonate and Subsequent AAS Determination. B . G. Stephens and H. L. Felkel, J r . (Spartanburg, SC, U S A ) . Coextraction and Extraction Suppression of Thallium(II1) in the Presence of Indium, Gallium and Iron(II1) in the Systems Trioctylamine - Hydrochloric Acid and Aliquat 336 - Hydro- chloric acid.L. J . Ottendorfer (Vienna, Austria). J . C. Veselsky (Sezbersdorf, Austria). V . V . Bagreev and Yu. I . Popandopulo (Moscow, USSR).May, 1977 FOURTH SAC CONFERENCE 119 Precolumn Capillary Gas Chromatography with Plasma Emission Detector. W . J . Kirsten Application of Chromatography to Automatic Analysis of Sulphur Compounds in Coke Oven Developments in GC and HPLC.Rapid Simultaneous Separation and Determination of Rare-earth Elements with the Ligand T . Fujinaga, T. Kuwamoto and T. Kimoto (Kyoto, Recent Developments and Applications of Low-energy Gamma-ray and X-ray Spectrometry in A4ctivation Analysis. IDEST-a Radioisotope Identification Subroutine for Use with Gamma-ray Spectrum Analysis Program SAMPO.Determination of Light-element Distributions with the Nuclear Microprobe. T . B . Pierce (Haywell, U K ) . Nuclear Microprobe Determination of the Distribution of Beryllium in Metals. J . W. McMillan, P . Hirst and F . C. W . Pummery (Harwell, U K ) . Radiochemical Analysis of Sulphide Ores Using Zn(DDTC), as Extractant.E. Pernicka, P . A . Schubiger and 0. Miiller (Heidelberg, West Germany). Ultrasonic Techniques for Remote Instrumentation of Chemical Plant : Applications in Nuclear Fuel Reprocessing. Analysis of Metals by Energy-dispersive X-ray Fluorescence. P. Verbeke, H . Nullens and F . Adams (Antwerp, Belgium). Analysis of Polymer Degradation Products by Ultraviolet Photoelectron Spectroscopy.D . Betteridge, D . Joyner, F . Greening, N . R. Shoko, M . E. A . Cudby, H . E. Willis and L. Henrick- son (Swansea and Welwyn, UK) . Analytical Applications of X-ray Photoelectron Spectroscopy. M . Thompson and E. J . Leventhal (Toronto, Canada). Proton-induced X-ray Emission-a Useful Analytical Method. G. Jolzansson, I?. A kselsson, M . Bohgard, L. E. Carlsson, H . Lannefors and K .Malmquist (Lund, Sweden). Application of Thermal Methods in the Analysis of Zinc Dialkyldithiophosphates. J . P. Dixon (Chester, U K ) . Thermal Analysis of Metal - Protein Complexes. The -2pplication of Thermal Analysis to the Investigation of High Molecular Weight Organic (Cppsala, Sweden). Gases. Dan P. Manka (Pittsburgh, USA). P. C. Uden (Amherst, U S A ) . Vapour Gas-chromatographic Method.Japan) * V . Krivan (Ulm, West Germany). W . Carder, T . D. MacMahon and A . Egan (Ascot, U K ) . R. .C. Aslzer (Harwell, UK). S . Gorinstein (Jerusalem, Israel). Compounds. J . Wieckowska ( Wroclaw, Poland). Tuesday, July 19th A New Method in the Analytical Laboratory-Flow Injection Analysis Systems with Medium Dispersion. Flow Injection Analysis Systems with Limited and Large Dispersion.E. H. Hansen and J . Rdz'ic'Ka (Lyngby, Denmark). Determination of Easily Osidised Compounds by Flow Injection Analysis and Redox Potential Detection. Bo Karlberg (SodertaZje, Sweden). Applications of Microprocessors to Analysis. The Determination of Viscosity by Flow Injection Analysis. A Low-pressure Microwave Plasma Cell for Analytical Applications. J .F. Alder and M . T. C. Cunha (London, U K ) . On-line Monitoring Techniques Using Ion-selective Electrodes. B. Fleet, G. P. Bound, W. F. Farrell, M. J . Connelley and R. N . Cockroft (London, U K ) . Microcomputers-Evolution or Devolution in Analytical Chemistry. G. C. Gidley and M. E. Jones (Sharnbrook, UK). Contributions to the Ring-oven Technique-Enzymatic Analytical Methods. H .Weisz (Freiburg, West Germany). The Role of Organic Ultramicro Elemental Analysis. Trace Analysis Without Matrix Eff ects-Micro-determination of Phosphorus Compounds. The Pyrolytic Behaviour of Some Solid Substituted Benzoic Acids. G. R. Hodges and G. Ingram J . RdiiEka and E. H . Hansen (Lyngby, Denmark). D . Betteridge, E. Dagless, P. David and D . R. Deans (Swansea and Wilton, UK). W.J . Kirstsn ( Uppsala, Sweden). 2. G. Szabd and I . K. Thege (Budapest, Hungary). (Portsmouth, UK).120 FOURTH SAC CONFERENCE Proc. Analyt. Div. Chem. SOC. C. Mackay, J . Tillmwz C. J . Little, A . D. Dale and lk?. B . A . Man&, G. S . G6orog and P. Horudth (Budapest, HPLC of Vitamin D and Its Determination in Multivitamin Tablets. and D. T. Burns (Loughborough, U K ) .Selectivity of Chemically Bonded Supports for HPLC. Evans (Welwyn, U K ) . HPLC of Some Metal Diethyldithiocarbamates on Microparticulate Silica. Parolari, E. Gaetani and C. F . Laureri (Parma, Italy). Mechanism of the Tetrazolium Reaction of Corticosteroids. Hungary). Ion-exchange Chromatography and Complex Formation. Separation and Sorption Studies of Metal Cations with Foam-supparted Extractants. J .Inczbdy ( Veszprkm, Hungary). M . Maloney, G. J . Moody, J . D . R. Thomas, T. Bvaun and A . B. Farag (Cardifl, U K and B d a - pest, Hungary). Application of Triethylenetetramine and Diaminopropane to Metal-ion Separation on Chelex 100. Determination of Minor Constituents of Coals and Cokes. H . C. Wilkinson (Chesterfielcl, U K ) . Current Research Projects in Air Pollution Control.H. E. Malone (California, U S A ) . GC Analysis of Organochlorine Compounds Using the Hall Conductivity Detector. R. J . Norstrom (Ottawa, Canada). Flow Measurement of Radioactivity in the Analysis of Organic Labelled Compounds by HPLC. V . Svoboda (Prague, Czechoslovakia). Application of a GC - AAS Combination for Speciation. J .W . Robinson and E . Keisel (Baton Rouge, USA). A New Voltammetric Method for the Study of Mercury Traces in Sea Water and Inland Waters. L. Sipos, P. Valenta, H . W. Niirnberg and M. Branica (Julich, West Germany and Zagreb, Yugoslavia). Distribution of Trace Elements in a River Measured by Neutron Activation Followed by High- resolution Photon Spectrometry. W. Haerdi, C. Bergerioux and J .P. Blanc (Geneva, Switzerland). Elemental Analysis of Airborne Particulates in an Indoor Environment by Simultaneous Use of PIXE and yRay Detection for Fluorine Analysis. K . Malnzqvist, R. A . Akselsson and G. Johansson (Lund, Sweden). Computer Techniques for Data Handling in Applied Spectroscopy. I?. J . Obremskz and J . Ramirez-Munoz (Califoornia, U S A ) . Computerised Identification of Chemical Compounds.J . Moravec, 0. Helmiclz, A . Vzteh and M . Hordk (Prague, Czechoslovakia). Applications of Computerised Infrared Difference Spectroscopy. J . P. Coates (Beaconsfield, U K ) . Analysis of Milk-fat GLC Data by Linear Discriminant Analysis. J . Smeyers- Verbeke, L. Kaufman and D. L. Massart (Brussels, Belgium). The “Thermo-Stat”-a Closed Stat-System for the Determination of Catalytically Active Substances. D.Klockow, G. Karenovics and W. Meiners (Dortmund and Freiburg, West Germany). K. Brajter and J . Grabarek (Warsaw, Poland). Accuracy and Manipulations with Metal Solutions. J . Kragten ( A msterdam, The Netherlands). Complexometric Titration of Copper and Other Elements with a New Metallofluorescent J . A . Rodriguez- Vazquez and F.Bermejo-Martinez (Santiago de CornPostela, Comparison of Alizarin Fluorine Blue and Sulphonated Alizarin Fluorine Blue (AFBS) as Interferences with the AFBS Method ; Their Nature and Removal. Indicator. Spain). Reagents For Fluoride. S. F . Deane and M. A. Leonard (Belfast, U K ) . Infrared Analysis of Asbestos and Quartz. Slurry Packing Comparison of Irregular and Spherical HPLC Adsorbents.R. A . C. Gray Spectrophotometric Determination of Zirconium with Halogen Derivatives of Phenylazo- A Critical Comparison of the Determination of Vitamin B, in Foods by a New HPLC Method D. J . Farrel, G. C. Gidley, A . D. Jones and J . P. Coates (Beaconsfield, U K ) . (Manchester, U K ) . chromotropic acid. and the “Standard” Microbiological Approach.P. J . Richardson (Sharnbrook, UK). M. Issa, M . M. Khater and S. S. Badawy (Cairo, Egypt).May, 1977 FOURTH SAC CONFERENCE 121 Study of Programme Steps in Furnace AAS with Lead-212. M . Stoeppler, M . Kampel and Determination of Heavy Metals in Aquatic Ecosystems with a Heated Graphite Atomiser. Development and Comparison of Methods for the Multi-element Pre-concentration from High- Analytical Uses of Propylene Carbonate and Subsequent AAS Determination.B . G. Stephens Determination of Nitrogen-containing Compounds by Molecular Emission Cavity Analysis R. Belcher, S . L. Bogdanski, A. C. Calokerinos and A . Townshend (Birminghana, Study of Mutual Interferences of Alkali Metals in AAS. I . Voinovitch, J . M . Liagre and G. Spectrophotometric Determination of Palladium and Cobalt Using Phenylazobenzaldosime.Ion-exchange Methods in Organic Analysis. Gas-chromatographic Determination of Halides. W . I. Stephen (Birmingham, U K ) . K . May (Julich, West Germany). G. J . van Rossum (Haten, The Netherlands). purity Manganese. (Spartanburg, U S A ) . (MECA). U K ) . Friant (Paris, France). A . E. Mahyoub, A . S . Shawali and M .M . Shoukry. E. Jackwerth (Dortmund, West Germany). M . Qureshi ( A ligarh, India). Thursday, July 21st Use of Optoacoustic Spectroscopy for Small Solid and Semi-solid Samples. G. F . Kirkbrigkt (London, U K ) . Applications of MECA Using a Vapour-generating System (the MECA-VAP). S. L. Bogdnnski (Birmingham, UK). The Use of MECA in the Analysis of Organobromine and Organochlorine Compounds.M . H . K . Abdel-Kader, M . E . Peach and D. A . Stiles (Wolfville, Canada). MECA Spectroscopy : an Appraisal of Its Application to the Measurement of Some Naturally Occurring Phosphorus Compounds. D. J . Knowles, P. Marviott and S. J . E. Slater (Bundoora, Australia). Absorption Spectroelectrochemistry a t a Platinum Electrode. J . F . Tyson and T . 5 . ]Vest (Loughborough and Aberdeen, U K ) .Gas-phase Molecular-absorption Spectroscopic Determination of Ions in Solution. AT. S . Cresser ( A berdeen, UK) . Developments on Carbon Furnace Atomic-emission Spectrometry. J . M . Ottaway, R. C. Hutton and D. Littlejohn (Glasgow, U K ) . Atomic-absorption Method for Direct Determination of Micro-impurities in Organic Materials. E. K . Vulfson, V .I . Dvorkin, A . V . Karyakin and A . F. Janushkevitch (MOSCOW, U S S R ) . Direct Read-out of Blood-lead Concentrations Using a Simple Integration - Microsampling Atomic-absorption Method. H . T . Delves, A . Schneider, R. B. Reasons and P. J . Kennedy (London, U K ) . The Design of an Atomic-fluorescence Flame Spectrophotometer for Analysis of Clinical Materials. Combination of Flame AAS and Ion-exchange Chromatography for the Determination of Copper and Zinc in Serum.Determination of Thallium in Environmental Samples. H . Muntau and J . Cantoreggi (Euratom, Switzevland) . Factors Governing the Application of Luminescence Spectroscopy to the Characterisation of Contact Traces in Forensic Science. The Use of Plasma-protein Profiling in the Discrimination of Blood-stains.J . N . Miller (Loughborough, U K ) . Determination of Daunorubicin and Daunorubicinol in Plasma from Leukaemic Patients. S . Eksborg and H . Ehrsson (Stockholm, Sweden). Analysis of Bacterial Activity in the Control of Activated Sludge Waste Treatment Plants. D. Barnes (Sydney, Australia). Improvements in pH Measurements and Standardisation. Metal-ion Adducts of Poly(propy1ene glycol) as Sensors for Ion-selective Electrodes.A . M . y . Jaber, G. J . Moody and J . D. R. Thomas (Cardifl, UK). New Chloramine-T and Picrate Ion-selective Electrodes. T . P. Hadjiioannou ( A thens, Greece). R. G. Michel, M . L. Hall, J . M . Ottaway and G. S . Fell (Glasgow, U K ) . H. T . Delves and P. J . Aggett (London, U K ) . J . B . F. Lloyd (Birmingham, UK).A . K . Covington (Newcastle, U K ) .122 FOURTH SAC CONFERENCE Proc. AnaZyt. Dzv. Chem. SOC. G. J . M. Heijne, W. E . A Critical Examination of Data Ion-selective Electrodes in Solutions Containing Complexing Agents. Determination of Stability Constants by pH Titrations. Application of Tiron as a Titrant. Amperometric Complex-formation Titrations with a Dropping Bismuth Amalgam Electrode in Halide Media.J . W. Dieker, W . E. van der Linden and G. den Boef (Amsterdam, The Netherlands). Developments in the Use of EDTA in the Direct Determination of Fluoride. S. G. Coles and D. A . Pantony (London, UK). Rapid Analysis of Primary Amines by a Combination of TLC and Fluorimetry. J . N . Miller (Loughborough, U K ) . Determination of 8-Methoxypsoralen in Plasma by Electron-capture GC.H . Ehrsson, S . Eksborg, I . Wallin, N . KaBberg and G. Swanbeck (Stockholm, Sweden). Scheme of Analysis for the Study of Small Calcifications. Y . Michotte, J . Smeyers-Verbeke, M . Collard, A . Lowenthal and D . L. Massart (Brussels, Belgium). Some Applications of Pulse Polarography and Coulometry in the Determination of Drug Com- pounds and Inorganics.Voltammetric Behaviour of Humic and Fulvic Substances in Natural Waters. J . Bu&?e, A . Cominoli, F . L. Greter and W. Haerdi (Geneva, Switzerland). Atmospheric Deposition of Heavy Metals in Norway. Analysis of Moss Samples by Neutron- activation Analysis and AAS. British Standards Institution-pH Standardisation Feature (Extended Poster Presentation). A . K . Covington (Newcastle, U K ) . Potentiometric Determination of Iodine in Pharmaceutical Preparations and Biological Material.M . Vandeputte, L. De Hertogh, L. Dyron and D . L. Massart (Brussels, Belgium). Factors Affecting the Ion-selective Electrode Monitoring of Chloride in Sweat. P . T . Bray, G. C. F . Clarke, G. J . Moody and J . D. R. Thomas (Cardifl, U K ) . Application of Ion-selective Electrodes to Continuous Analysis of Steelworks Effluents.M. E. Hofton (Middlesborough, U K ) . Equilibrium and Kinetic Studies in Phosphoric Acid Media with a Fluoride-selective Electrode. Y . Israel, J . Rezek and B . Paschkes (Haifa, Israel). DC and Differential Pulse Polarography for Assay of the Growth Stimulator Nitrovin in Animal Feeds and Biological Material. Aspects of Flow Injection Analysis.Separation and Determination of Co-existing Forms of Silicic Acid in Natural Waters and Technological Solutions. G. M . Varshal, L. V . Dracheva and N . S . Zamokina (Moscow, USSR). van der Linden and G. den Boef (Amsterdam, The Netherlands). Handling. W. A . E. McBryde and T . B . Field (Watevloo, Canada). G. den Boef (Amsterdam, The Netherlands).A . G. Fogg (Loughborough, U K ) . E. Steinnes (Kjeller, Norway). I . Sestdkovd (Prague, Czechoslovakia). K. K . Stewart (Maryland, U S A ) . Friday, July 22nd Some Factors Affecting the Usefulness of an ICP Source. Some Recent Studies with Radiofrequency and Microwave-excited Plasma Sources in Atomic- Determination of Aluminium by High-frequency Plasma Spectrometry. T . Suzuki (Nagoya, Study of Processes Involved in Spectral Analysis of Trace Elements.L. I . Pavlenko, L. V . Simonova, G. G. Babicheva and A. V . Karyakin (Moscow, USSR). Mechanism of Atom Losses in Graphite Furnace AAS. R. E. Sturgeon and C. L. Chakrabarti (Ottawa, Canada). Furnace AAS Using an Atomiser with a Resistance Sensor for Precise Temperature Control. J . E. Cantle and C . Kirby (Stockfiort, U K ) .Determination of Trace Elements in Steels and Nickel-base Alloys by AAS with an Induction Furnace. D. G. Andrews, A . M. Aziz-Alraham, J . B. Headridge and R. Thompson (Shefield, U K ) . Precision in Flameless AAS. A Mass-spectrometric Survey of Metal Chelates. S. Greenfield (Oldbury, U K ) . emission Spectroscopy. G. F. Kirkbright (London, UK). Japan). Direct Analysis of Solid Samples.J . Fazakas (Bucharest, Rumania). J . R. Majer and E. El-Kuwaiti (Birmingham, UK) .May, 1977 FOURTH SAC CONFERENCE 123 D. E . F . de Ceuninck and F . Adams M . Thompson, P. A . Hewitt and D . S . Wolliscroft (Toronto, Applications of Newer Mass-spectral Techniques in the Analysis of Organic Compounds. Digital Electrical Detection Spark-source Mass Spectrometry.Auger Electron Spectrometry. The Analytical Approach. Advances in Rapid Sample Preparation for X-ray Spectrometry by Induction Fusion. 13. Recent Developments in Candoluminescence Spectrometry. A . Townshend (Birmingham, C K ) . Determination of Traces of Antimony, Indium and Gallium by Candoluminescence Spectro- Coulometry in Non-aqueous Media. E . A . M . F. Dahmen and M .Bos (Enschede, The Nethev- Derivative Potentiometric Stripping Analysis of Trace Metals. The Triangle Programmed Titration Technique-a Xovel Technique for the Analysis of Steamed Samples. The Chalcocite Copper Ion-selective Electrode and Its Analytical Applications. A . Hulanicki, M . Trojanowicz and T . Krawczynski vel Krawczyk (Warsaw, Poland). Oscillopolarographic Determination of Traces of Tungsten and Molybdenum Micro-amounts.A . M . Demkin (Moscow, USSR). Role of Complexing During the Determination of Metals of the Iron Group by Inverse Voltam- metry. Inverse Voltammetry and Chronopotentiometry of Copper and Silver on a Rotating (Carbo- sitall) Disc Electrode. 0. L. Kabanova, Yu. A . Gonchavov and S . M . Beniaminova (Moscow, USSR). Polarographic Determination of Traces of Non-ionic Surfactants.I . Zjawiony and 2. Klinza (Katowice, Poland). Studies of the Chromogenic Properties of Chlorogenic Acid. I . I . Costou and G. E. Baiulescu (Buchavest, Rumania). The Reaction of Cerium with Methyl Thymol Blue. Determination of Cerium in Non-aqueous Media. Spectrophotometric Determination of Palladium Using p-Aminophenylmercaptoacetic Acid.E . Fernkndez-Gdmez, J . A . Rodriguez- Vazquez, F . Bermejo-Martinez and A . Concheivo-Nine (Santiago de Compostela, Spain). Spectrophotometric Determination of Vanadium(V), Cerium(III), Arsenic(II1) and Nitrite with Mepazine Hydrochloride. Automated Enthalpimetric Analysis of some Fertilisers. U . M . Abassi and L. S . Bark (Salford, UK). ,4 Kew Potentiometric Method for the Determination of Iridium, Zirconium and Thorium.H . Khalifa, Y . M . Issa and M . S . Okda (Cairo, Egypt). Simultaneous Micro-determination of C, H, C1, Br, S and Hg in Organic and Organomercury Compounds. Analytical Applications of Chromyl Chloride. Determination of Chloride in Biological Fluids. L . Polo-Diez (Salamanca, Spain). Further Studies of the Solvent Effect on the Apparent Stability of Metal and Proton Com- plexes.Spectrofluorimetric Determination of Cerium in Carbon and Low-alloy Steels. D. T . Buvns (Belfast, U K ) . Application of Ion-exchange in the Analysis of Oxide Catalysts; Quantitative Separation of Copper, Iron and Zinc in a Low-temperature Co-conversion Catalyst. S . Dutta-Chaudhuri (Bihar, India). Techniques for the Determination of Mercury in Sterically Hindered Organomercurials.D. T. Burns, F . Glockling and W . J . Swindall (Belfast, U K ) . Removal of Co-extracted Reagent in Solvent Extraction of Metal Chelate Anions with Quater- nary Ammonium Salts. Spectrophotometric Determination of Nickel with 2-Nitroso- 1- naphthol-4-sulphonic acid. Games, J . L. Gower, M . G. Lee, I . A . S . Lewis, M .E. Pugh and M . Rossiter (Cardifl, U K ) . (Antwerp, Belgium). Canada and Loughborough, U K ) . C. A . Lucchesi (Euanston, USA). Bogdain (Munich, West Germany). metry. lands). R . Belcher, T . A . K . Nasser and A . Townshend (Birmingham, U K ) . D . Jagnev (Goteborg, Sweden). G. Nagy, 2s. Fehh, K . Tdth and E. Pungor (Budapest, Hungary). I . V . Markova (Moscow, USSR). A . Cabrera-Martin and M .C . Cartagena (Madrid, Spain). H . S . Gowda and K . N . Thimnzaian (Mysore, India). A . B . Sakla, M . R. 0. Kavim and B. N . Bassoum (Cairo, Egypt). W . A . E . McBryde, T . B. Field and E . Nieboer (Waterloo, Canada). K . TGei and S . Motomizu (Okayama, Japan), Photometric Determination of Metronidazole. A . P . Basu (Calcutta, India).124 FOURTH SAC CONFERENCE Proc.Analyt. Div. Chem. SOC. Ion-selective Electrodes for Basic and Acidic Dyes. K. S. Yov and A . G. Fogg (Loughborough, Diazotisation and Coupling as a Derivatisation Technique in the Differential Pulse Polarography UK) . of Drugs. Y . 2. Ahmed and A . G. Fogg (Loughborough, U K ) . Oration On Friday, July 22nd, there will be an oration by Dr. W. I. Stephen on Professor R.Belcher. Exhibition of Manufacturers' Equipment There will be a comprehensive exhibition of manufacturers' equipment from Monday, July 18th, to Thursday, July 21st. Sessions by Specialist Subject Groups of the Analytical Division Monday, July 18th Chromatography and Electrophoresis Group Particle Size Analysis Group Thermal Methods Group Radiochemical Methods Group Tuesday, July 19th Biological Methods Group Automatic Methods Group Microchemical Methods Group Thursday, July 21st Joint Pharmaceutical Analysis Group Electroanalytical Group Atomic Spectroscopy Group Workshop Sessions Tuesday, July 19th Teaching Aids. Education and Training Group. Black Boxes. Special Techniques Group. Thursday, July 21st Optoacoustic Spectrometry. G. F. Kirkbright. Microprocessors and Flow Injection Analysis. MECA (Molecular Emission Cavity Analysis). D. Betteridge, E. H . Hansen, J . Riz'ic'ka and K. K. Stewart. S. L. Bogdanski and A. Townshend. Social Programme and Scientific Visits In addition there is a Social Programme, including provisions for scientific visits, to which the whole of Wednesday, July 20th, will be devoted and from which a selection of the large range of alternatives can be made. A Ladies' Programme has been arranged. Registration Early registration is advised (there will be a late fee payable after June 3rd, 1977). Details and registration forms can be obtained from Miss P. E. Hutchinson, Secretary, Analytical Division, The Chemical Society, Burlington House, Piccadilly, London, W1V OBN.

ISSN:0306-1396    

DOI:10.1039/AD9771400118

出版商:RSC    

年代:1977

数据来源: RSC

摘要:

May, 1977 REVISED BRITISH STANDARD FOR GRADUATED PIPETTES 125 International Analytical Commission of the Comite International des Derives Tensio-actifs The International Analytical Commission (CIA) of the CID held its 20th meeting on November 4th and 5th, 1976, in Paris on the invitation of the Comitb Franqais de la Dbtergence. Repre- sentatives from various European countries took part in this meeting.A representative of IUPAC and two members of the ISO/TC-91 Committee were also present. The CIA’S work is carried out by scientists whose companies belong to the CID’s member committees. The questions studied by the commission have been approved by those companies. The CIA is, a t the present time, studying the following questions. Analysis of the inorganic constituents of washing powders.A gravimetric method for the determination of silicates in washing powders has been adopted (doc. CIA 100-22- 76). The working group is continuing its work on the determination of borate, inorganic sulphate, carbonate and available oxygen in the presence of sequestering agents. Several methods will be tested this year in collaborative analyses within the working group. A new collabor- ative analysis among 16 laboratories will be carried out in order to check the method for the determination of the average equivalent mass. Determination of inorganic sulphate an organic sulphates and sulphonates.A comparison be- tween three variants of a titrimetric method is being completed. The selected method will be circularised to the CIA members to be approved before it is forwarded to ISO.Analysis of alkylsulphonates. Polyethoxylated alkylphenols and alcohol sul- Phates. A collaborative analysis among 22 laboratories will deal with three determinations : total surface-active agent, non-ionic fraction and polyglycol sulphate. Determination of ethylene oxide and propylene oxide mixture by Pyrolysis chromatography. The method will be re-drafted to limit its field of application to the relative ethylene oxide to propylene oxide ratio.Analysis of ethoxylated fatty amines. The French commission will re-draft the method CIA 105-03-76 to take into account the remarks received. The new draft will be sent to I S 0 to become an international standard. Dioxan being a carcinogenic substance, an item “Secur- ity” will be added to the standard to indicate the risk incurred and precautionary measures to be taken.Quantitative determination of alkanolamides. Great Britain will carry on the preliminary work of selecting methods. When it has completed this selection, i t will circularise a report to the CIA members indicating more particularly the reasons why certain methods have been dis- missed.Following this preliminary investiga- tion, Czechoslovakia, France, Spain and the USSR will join Great Britain to study this question. Quantitative determination of hydrotropes. The working group on hydrotropes will meet a t the beginning of 1977 in order t o study the results of the collaborative analyses made during 1976 on the total active matter, the water con-126 TECHNICON SCHOLARSHIP Proc.AnaZyt. Div. Chew. SOC. tent and the inorganic matter. A report on the work completed up to now will be circularised among the CIA members. Analysis of alkylphosphates. Two methods for the determination of phosphated matter by ion exchange will be compared by the French and Swedish commissions. After a method has been selected a collaborative analysis will be carried on among 15 laboratories to test ethoxylated products.The French and Soviet commissions will compare their methods for the determination of mono- and dialkylphosphates in order to select one of them for a collabora- tive analysis. Technical sodium alkylbenzene sulphonates. -4 collaborative analysis among ten laboratories will be carried on to check the method presented by the Dutch commission (documents CIA This is a new subject on the CIA’S agenda. To begin with a Dutch - French working group will analyse the technical information to select from among the existing methods those likely to solve the problems raised by sequestering agents and will consider whether it is necessary to elaborate two methods, one for soaps and another for washing products. The CIA will hold its 21st meeting on October 6th and 7th, 1977. Interested parties can obtain CIA methods at the CID’s secretariat, 5 bd. de Latour-Maubourg, 75007 Paris, France. 112-02- to 112-04-76). Determination of sequestering agents.

ISSN:0306-1396    

DOI:10.1039/AD977140125b

出版商:RSC    

年代:1977

数据来源: RSC

摘要:

126 TECHNICON SCHOLARSHIP Proc. Analyt. Div. Chenz. SOC. Chemical Society Library The following publications of analytical interest have been added to the Library since the last list appeared in Proceedings (1977, 14, 43). Thermometric Titrations. J. Barthel. Wiley. 1975. Extraction Chromatography. T. Braun and G. Ghersini. Elsevier. 1975. The Chemistry of Phosphorus : Environ- mental, Organic, Inorganic, Biochemical and Spectroscopic Aspects.J. Emsley and D. Hall. Harper and Row. 1976. Resource Book on Chemical Education in the United Kingdom. M. J. Frazer and R. J. Sleet. Heyden. 1975. Solubility of Gases and Liquids: a Graphic Approach. Data, Causes, Prediction. W. Gerrard. Plenum. 1976. Handbook of Organic Reagents in Inorganic Analysis. 2. Holzbecher et al.Ellis Horwood. 1976. Structural Studies of Macromolecules by Spectroscopic Methods. Edited by K. J. Ivin. Wiley. 1976. Dynamic Nuclear Magnetic Resonance Spectroscopy. Edited by L. M. Jackman and F. A. Cotton. Academic Press. 1975. Microscale Manipulations in Chemistry. T. S. Ma and V. Horak. Wiley. 1976. Organic Functional Group Analysis by Gas Chromatography. T. S. Ma and A. S.Ladas. Academic Press. 1976. Membrane Separation Processes. P. Meares. Elsevier. 1976.May, 1977 CONFERENCES AND MEETINGS Characterization of Coatings: Physical Techniques. Part 2. Edited by R. R. Myers and J. S. Long. Dekker. 1976. Handbook of Analysis of Organic Solvents. V. Sedivec and J . Flek. Ellis Horwood. 1976. Detectors in Gas Chromatography. J. Sevcik. Elsevier. 1976. Chromatographic and Electrophoretic Techniques. 4th Edition. Volume 1. Paper and Thin-Layer Chromatography. Volume 2. Zone Electrophoresis. Edited by I. Smith and J. W. T. Seakins. Heinemann. 1976. Trace Analysis : Spectroscopic Methods for Elements. Edited by J . D. Winefordner. Wiley. 1976. Analytical Methods for Pesticides and Plant Growth Regulators. Volume 8. Govern- ment Regulations, Pheromone Analysis, Additional Pesticides. Edited by G. Zweig and J. Sherma. Academic Press. 1976. 127

ISSN:0306-1396    

DOI:10.1039/AD977140126b

出版商:RSC    

年代:1977

数据来源: RSC