iv SUMMARIES OF PAPERS I N THIS ISSUE August, 1983Summaries of Papers in thisCombination of Flow Injection Analysis with Flame Atomic-absorption Spectrophotometry : Determination of Trace Amountsof Heavy Metals in Polluted SeawaterA simple flow injection system, the FIAstar unit, was used to inject samplesof seawater into a flame atomic-absorption instrument allowing the deter-mination of cadmium, lead, copper and zinc a t the parts per million level a ta rate of 180-250 samples per hour. Further, on-line flow injection analysispre-concentration methods were developed using a microcolumn of Chelex- 100resin allowing the determination of lead a t concentrations as low as 10 partsper loB (p.p.b.) and 1 p.p.b. for cadmium and zinc. The sampling rate wasbetween 30 and 60 samples per hour and the readout was available within60-100 s after sample injection; the sampling frequency depended on thepre-concentration required.Keywords : Heavy metals determination ; flow injection analysis ; flameatomic-absorption spectrophotornetry ; trace awnlysis ; polluted seawaterSVEND OLSEN, LUIZ C.R. PESSENDA, JAROMIR RfikICKA andEL0 H. HANSENChemistry Department A, The Technical University of Denmark, Building 207,DK-2800 Lyngby, Denmark.Analyst, 1983, 108, 905-917.Determination of the Chemical Forms of Cadmium and Silver inSediments by Zeeman Effect Flame Atomic-absorptionSpectrometryA polarised Zeeman flame atomic-absorption spectrometer has been used forthe determination of cadmium and silver in chemical extracts of sedimentsusing a procedure designed to provide information on the potential availabilityof trace elements.The limit of determination for complex solution matriceswas found to be 1.1 pg 1-1 for both cadmium and silver. Minimum base-linenoise for the instrument afforded very good stability of the calibration con-ditions a t the 10 pg 1-1 level for the two elements. Accuracy tests performedwith standard reference materials showed good agreement for the determi-nations in the extracts. The analysis of suspended and bottom sediments isused to demonstrate the value of this instrumental technique.Keywords : Zeeman game atomic-absorption spectrometry ; chemical forms ;cadmium determination ; silver determination ; sedimentsKEN R.LUMEnvironmental Contaminants Division, National Water Research Institute, CCIW,P.O. Box 5050, Burlington, Ontario L7R 4A6, Canada.and DUART G. EDGARNissei Sangyo Canada Inc., 89 Galaxy Blvd., Suite 14, Rexdale, Ontario M9W 6A4,Canada.Analyst, 1983, 108, 918-924August, 1983 SUMMARIES OF PAPERS I N THIS ISSUE VDetermination of Caesium and Rubidium by Flame and FurnaceAtomic- absorption SpectrometryCaesium and rubidium have been determined by flame and furnace atomic-absorption spectrometry. It was found that both techniques are reasonablyfree from interferences and accurate enough for the routine analysis of varioustypes of samples.Keywords : Caesium determination ; rubidium determination ; atomic-absorptionspectrometry2. GROBENSKI, D.WEBER, B. WELZ and J. WOLFFBodenseewerk Perkin-Elmer & Co. GmbH, Postfach 1120, D-7770 Uberlingen,Federal Republic of Germany.Analyst, 1983, 108, 925-932.Pyridine-2-aldehyde 2-Furoylhydrazone as a Fluorogenic Reagentfor the Determination of Nanogram Amounts of GalliumThe synthesis, characteristics and analytical applications of pyridine-2-aldehyde 2-furoylhydrazone (PAFH) are described. This compound hasbeen examined to evaluate its usefulness as a selective and sensitive spectro-fluorimetric reagent for gallium. The method is applied in 0.8% ethanolicsolution a t pH 4.5. Under these conditions the fluorescent species haveexcitation and emission maxima a t 380 and 445 nm, respectively. Thedetection limit is 0.8 ng ml-l and the range of application is between 1 and50ngml-l.The method has been employed to determine gallium in syn-thetic mixtures and its recovery from human urine samples.Keywords: Gallium determination; pyridine-2-aldehyde 2-furoylhydrazonereagent ; spectrofluorimetryELOISA REQUENA, JOSR J. LASERNA, AURORA NAVAS andFRANCISCO GARCfA SANCHEZDepartment of Analytical Chemistry, Faculty of Sciences, University of MAlaga,MQlaga-4, Spain.Analyst, 1983, 108, 923-938.Spectrophotometric Determination of Arsenic in Biological Tissuesand Sediments After Digestion With Nitric, Sulphuric andPerchloric Acids and Pre- concentration by Zinc Column ArsineGeneration and TrappingA procedure for the determination of total arsenic in environmental extractsis described.Arsenic is converted into arsine using a zinc reductor column,the evolved arsine trapped in a potassium iodide - iodine solution and thearsenic determined spectrophotometrically as an arsenomolybdenum bluecomplex. The detection limit (based on four times the standard deviationof six blank measurements) is 0.024 p g and the coefficient of variation is 5.1 yoat the 0.1- pg level. The method is free from interferences by other elementsa t levels normally found in environmental samples.Keywords : Arsenic determination ; hydride generation and trapping ; mole-cular-absorption spectrophotometry ; environmental materialsW. A. MAHERDepartment of Oceanography, University of Southampton, Southampton, SO9 SNH.Analyst, 1983, 108, 939-943vi SUMMARIES OF PAPERS IN THIS ISSUESpectrophotometric Determination of Phosphorus and Arsenic inSteel by Solvent Extraction of their Heteropolyacids with Ethyl VioletAugust, 1983Under the same conditions, orthophosphate and ortlioarsenate react withmolybdate to form molybdophosphate and arsenomolybdate, which areextracted into a cyclohexane - 4-methylpentan-2-one mixture (1 + 3) withethyl violet.The absorption spectrum of each ion pair, extracted into theorganic phase, is almost the same in the visible region and the molar absorp-tivity of each ion pair in the organic phase is 2.8 x lo6 1 mol-l cm-l a t 602 nm.In determining phosphate, arsenate can be masked with thiosulphate andhydroxylamine. The arsenate concentration was obtained by subtractingthe phosphate concentration from the total concentration of phosphate andarsenate.Steel samples (less than 0.25 g in mass) were dissolved in aquaregia and the solution was diluted to 11 with distilled water. In the deter-mination of phosphorus (about 0.003y0) and arsenic (about 0.007~0) in steel,the relative standard deviations were 2.5 and 2.1 Yo, respectively. Fifteenstandard steel samples were analysed, and the results obtained for phosphorusand arsenic were in good agreement with their certified values. The resultsfor the recovery test were also good. The limit of detection for both phosphorusand arsenic is about O.OOlyo in steel.Keywords Phosphorus and arsenic determination ; solvent extraction ; hetero-polyacid; steel analysis ; ethyl violetSHOJI MOTOMIZU, TOSHIAKI WAKIMOTO and KYOJI TOE1Department of Chemistry, Faculty of Science, Okayama University, Tsushima-naka,Okayama-shi, JapanAnalyst, 1983, 108, 944-951.Extraction and Spectrophotometric Determination of Titanium( IV)with N- Phenyllaurohydroxamic Acid and PhenylfluoroneN-Phenyllaurohydroxamic acid reacts with titanium(1V) in 9-10 Mhydrochloric acid to give a coniplex that is completely extractable intosolvents such as hexane and chloroform.The chloroform extract of thetitanium complex, on second extraction from a dilute hydrochloric acidmedium (0.1-0.5 M), in the presence of phenylfluorone and isoaniyl alcohol,forms an intensely coloured complex possessing an absorption maximum at540 nm. Even though the molar absorptivity of the complex under optimumconditions at 540 nm is 2.33 x lo5 1 niol-l cm-l, the measurements are moreprecise at 560 nm with a molar absorptivity of 1.23 x lo5 1 mol-l cm-l.Thesystem obeys Beer’s law for up to 0.4 p.p.m. of titanium(1V). Considerableamounts of many cations and anions including a 350-fold molar excess ofiron(II1) can be tolerated. Interference from zirconium(1V) can be mitigatedor even eliminated by the addition of fluoride ions. The method can beapplied to the determination of titanium present at 10 parts per lo9.Keywords : Titanium(I V ) determination ; spectrophotometry ; N-phenyllauro-hydroxamic acid; Phenyljuorone ; liquid - liquid extractionH. DASARATHA GUNAWARDHANATrace Analysis Research Centre, Chemistry Department, Dalhousie University,Halifax, Nova Scotia, B3H 4 J 1, Canada.Analyst, 1983, 108, 952-958August, 1983 SUMMARIES OF PAPERS IN THIS ISSUESpectrophotometric Determination of Rhodium(II1) in Aqueousand Alcoholic Media Using 2- Thiobarbituric AcidA spectrophotometric study of the rhodium(II1) - 2-thiobarbituric acidsystem is presented.Rhodium(II1) forms 1 : 2 and 1 : 4 complexes with 2-thio-bartituric acid in water and 98% ethanol, respectively. Conformity toBeer’s law a t 327 nm was observed for up to 14 pg ml-l of rhodium in waterand for up to 12 p g ml-l in 98% ethanol and the detection limits were 0.24and 0.34 pg ml-l of rhodium, respectively. Molar absorptivities at 327 nmin aqueous and alcoholic media were 1.04 x lo4 and 1.08 x lo4 1 mol-l cm-land Sandell’s sensitivities were 0.009 8 and 0.099 5 pg cm-2, respectively.The tolerance of the system to platinum metals and other common cationsis reported, the method is evaluated and a comparison with the maincolorimetric methods for rhodium determination developed in recent years ispresented.Keywords : Rhodium determination ; 2-thiobarbituric acid ; spectrophotometryBASIL10 MORELLIUniversitk degli Studi di Bari, Dipartimento di Chimica, Via Amendola 173, 70126-Bari, Italy.Analyst, 1983, 108, 959-965.ViiRapid Spectrophotometric Determination of Saccharin in SoftDrinks and Pharmaceuticals Using Azure B as ReagentSaccharin reacts quantitatively with Azure B in disodium hydrogen ortho-phosphate - citric acid buffer forming a blue product that can be extractedinto chloroform.Beer’s law is valid over the concentration range 2-68 pg ml-lof saccharin and the molar absorptivity is 2.4 x lo3 1 mol-l cm-l. Reasonableamounts of ingredients that are likely to be present in soft drinks and pharma-ceuticals do not interfere. Recoveries of saccharin from soft drinks andpharmaceuticals were satisfactory.Keywords : Saccharin determination ; spectrophotometry ; soft drinks ; fiharma-ceuticals; Azure BP. G. RAMAPPA and ANANT N. NAYAKDepartment of Post-Graduate Studies and Research in Chemistry, University ofMysore, Manasa Gangotri, Mysore-570006, India.Analyst, 1983, 108, 966-970.Interfacing an Automatic Elemental Analyser with an Isotope RatioMass Spectrometer: the Potential for Fully Automated TotalNitrogen and Nitrogen- 15 AnalysisAn interface between an automatic nitrogen analyser and an isotope massspectrometer is described.The interface enables total nitrogen analyses andnitrogen isotope ratio measurements to be made semi-automatically, a t therate of 12 h-l. The precision of the measurements was a t the detection limitof the mass spectrometer (0.00026 atom-% 15N; &0.7O/oO). No significantcross-contamination between samples was observed (< 0.02% carry over).The potential for full automation and extension of the interface for otherstable isotope measurements is discussed.Keywords : Nitrogen- 15 isotope mass spectrometry ; automatic nitrogen analysis ;elemental gas chromatograph - mass spectrometer interfaceTHOMAS PRESTONScottish Universities Research and Reactor Centre, N.E.L. Estate, East Kilbride,Glasgow, G75 OQU.and NICHOLAS J.P. OWENSNatural Environment Research Council, Institute for Marine EnvironmentalResearch, Prospect Place, The Hoe, Plymouth, PL1 3DH.Analyst, 1983, 108, 971-977viii SUMMARIES OF PAPERS I N THIS ISSUEDetermination of Phosgene in Methylene Chloride AfterCgclisation With a 2-Hydroxyamine and Gas ChromatographyWith Nitrogen-selective DetectionAugust, 1983A convenient and simple method for the determination of phosgene inmethylene chloride has been developed. An aliquot of the sample is mixedwith a solution of metoprolol or 2-aminophenol, in an excess. After a reactiontime of 10 min the solution is taken to dryness and the cyclic derivativeanalysed by gas chromatography with nitrogen-selective detection.Theprecisions (relative standard deviation) a t the 40 and 10 ng nil-l levels were3.9 and 7.3% for metoprolol and 3.3 and 3.6% for 2-aminophenol, respec-tively. The absolute yields at the 40 ng ml-l level were 91 and 95%, respec-tively. The present limit of detection is approximately 1 ng ml-1. Phosgeneappeared in methylene chloride (> 2 ng ml-l) stabilised with 20 p.p.m. ofamylene within 3 d if stored in clear glass in the presence of daylight. After15 d the 100 ng ml-l level was reached.Keywords : Phosgene determination ; 2-hydroxyamines ; gas chromatography ;nitrogen-selective detection; methylene chlorideOLLE GYLLENHAALAnalytical Chemistry, AB Hassle, S-431 83 Molndal, Sweden.Analyst, 1983, 108, 978-983.Simultaneous Gas- chromatographic Analysis of Lower Fatty Acids,Phenols and Indoles in Faeces and Saliva Using a FusedSilica Glass Capillary ColumnThe simultaneous gas-chromatographic separation of a mixture of 14 lowerfatty acids, 11 phenols and 7 indoles was performed by using a fused silicaglass capillary column of Carbowax 20M (50 m x 0.2 mm i d ., Carbowax20M deactivated). Complete separation of the mixture was obtained, exceptfor the peaks of phenols and o-cresol, o-ethylphenol and 3,5-xylenol andpelargonic acid, 2,3-xylenol and lt2-dimethy1indole, whose peaks overlapped,and 2- and 3-methylindoles, which were poorly separated. The optimumconditions are as follows: column temperature, held for 1 min at 100 "C;column oven, heated at 4 "C min-1 from 100 to 220 "C, maintained at 220 "Cfor 9min for standard compounds or 29min for sample specimens, thencooled to 100 "C; and carrier gas (nitrogen) flow-rate, 0.97 ml min-l. Themethod was applied to the analysis of the lower fatty acids, phenols andindoles in cat and human faeces and non-smoker saliva.Keywords : Gas chromatography ; fused silica glass capillary column ; faecesanalysis ; lower fatty acids, phenols and indolesYASUYUKI HOSHIKA and NINZO MURAYAMADepartment of Hygiene, Shinshu University School of Medicine, 3-1-1, Asahi,Matsumoto-shi, Nagano, 390, Japan.Analyst, 1983, 108, 984-990