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Fast gradient high performance liquid chromatography (HPLC) has been combined with a commercially available Fourier transform ion cyclotron resonance (FTICR) mass spectrometer for the routine and high performance analysis of mixtures. With this combination we were able to separate and detect, under high mass accuracy conditions, a six‐component drug mixture in less than 5 minutes. The fast gradients described are now possible due to the development of mechanically robust, ultra pure silica packing materials, which allow relatively high flow rates (ca. 1 mL/min for a 2 mm diameter column). For the six compounds present in the model mixture, relative mass errors of less than 1 ppm were obtained (based on an external calibration) providing sufficient mass accuracy to make unequivocal assignments of empirical formulae. Preliminary results of fast gradient HPLC/FTICR‐MS/MS are also shown for the same six‐component mixture. Copyright © 2000 John Wiley & Sons, Ltd.

Immunohistochemistry was used to analyse 18- and 26-month-old transgenic mice overexpressing the human β-amyloid precursor protein under the platelet-derived growth factor-β promoter with regard to presence and distribution of neuropeptides. In addition, antisera/antibodies to tyrosine hydroxylase, acetylcholinesterase, amyloid peptide, glial fibrillary acidic protein and microglial marker OX42 were used. These mice have been reported to exhibit extensive amyloid plaques in the hippocampus and cortex [Masliah et al.(1996) J. Neurosci.16,5795–5811].

A potential drug candidate containing a multiplicity of sulphur atoms, and one unknown in vivo main metabolite, were analysed with an high performance liquid chromatograph time‐of‐flight mass spectrometer (LC/TOF‐MS). Sensitivity and resolution were compared with those obtained with a quadrupole instrument. The LC/TOF‐MS provided a more than 200‐fold advantage in sensitivity, higher resolving power for the isotopic envelopes of the molecular ions produced by electrospray, and simple procedures for the determination of elemental composition. The exact masses of the candidate and its main metabolite were determined to within 1.5 to 3 ppm, using a single lock mass correction. Copyright © 1999 John Wiley & Sons, Ltd.

Combined gas chromatography mass spectrometry, because of its ability to provide both high sensitivity and specificity, has become a vital technique for the identification and quantitation of natural and synthetic chemicals in a wide variety of areas. Unfortunately, a very large number of organic compounds are not directly amenable to gas chromatography since they are thermally labile and/or of low volatility. Chemical modification of compounds of interest can assist in some cases, but it is not universally applicable. High performance liquid chromatography has been increasingly utilized for studies of compounds of these types since heat is not usually involved in the analysis. Combined liquid chromatography mass spectrometry would lend a new dimension to these studies, enabling the separating ability of the liquid chromatograph to be combined with the sensitivity and specificity of the mass spectrometer. Approaches to liquid chromatography mass spectrometry are discussed. Using examples from our liquid chromatographic mass spectrometric studies of natural compounds, drugs and pesticides, the current abilities of such systems to identify and quantify natural and synthetic chemicals present in a complex matrix of other chemicals are described.

Using mono-, di-, tri- and tetrasaccharides, nucleosides, bile acids, riboflavin, gibberellin A3, aminoglycosides, flavanoid and cardenolide glycosides, the sodium salt of riboflavin phosphate and the quaternary ammonium drug propantheline bromide, the performance of a new moving belt interface for liquid chromatography mass spectrometry has been evaluated. It is shown to be superior to previous interfaces of this type in its ability to provide relative molecular mass information from thermally labile low volatility compounds. The spech a obtained are similar to those obtained by desorption chemical ionization.

Heterocyclic aromatic amines (HAAs) are formed in cooked meats through pyrolysis reactions of different amino acids in the presence or absence of creatine/creatinine and sugars. HAAs are mutagens, colon/mammary gland carcinogens in rodents, and are suspected in the etiology of human cancers. In this study, cooked meats containing incurred HAAs as well as control (microwave) meat, were spiked with four labeled HAA internal standards (MeIQx, IQ, AAC and PhIP) and extracted using a liquid/liquid cleanup procedure. Isotope dilution measurements were made using on‐line liquid chromatography atmosphere pressure chemical ionization tandem mass spectrometry with multiple reaction monitoring to provide the sensitivity and specificity needed for trace analysis in these complex matrices. The procedure was validated using control meat spiked with the four native HAAs at 0–50 ppb. The levels of HAAs found in cooked meats ranged from non‐detectable (limit of detection 0.1–1.0 ppb) in microwave‐cooked hamburger to 226 ppb PhIP and 104 ppb AAC in well‐done grilled chicken. This methodology has the potential to provide accurate data on the consumption of HAAs in the diet for use in human cancer risk assessment. © 1997 John Wiley & Sons, Ltd.

We outline simple methodology for the rapid and selective analysis of 2‐aminoacridone (2‐AMAC) derivatised oligosaccharides by matrix‐assited laser desorption/ionization mass spectrometry. This involves the addition of small amounts of lithium chloride to the matrix before evaporation of solvent and crystallization. Signals mainly attributed to proton, sodium and potassium adducts are suppressed to a great extent, and a single signal due to (M + Li)+is observed. This technique is rapid and is most useful for the direct analysis of complex glycan mixtures, after derivatization with 2‐aminoacridone and without separation of the individual components. © 1997 John Wiley & Sons, Ltd.

The occurrence inHotea gambia adults of a sexual dimorphism in the divided dorsal abdominal scent gland (dg 1)is reported. Counts made of ducted secretory units indicate that female dg 1 regresses at the end of larval development, unlike male dg 1 which undergoes no regression. Other dorsal abdominal scent glands (dg 2, dg 3) which function in the larvae cease to function during the imaginai moult. From gas chromatographic, mass spectrometric and [1H]NMR data, the identity of the secretion from male adult dg 1 was established as virtually pure (E)-2-hexenol (a 100-mg mature male adult contains 0.5–1 µl of secretion). 2-Hexenol was also found in the reduced female adult dg 1. In the sexually monomorphic metathoracic scent gland, (E)-2-alkenals (C6, C8) and (E)-4-oxohex-2-enal, together with monoterpenes (ß-pinene, limonene) but not 2-hexenol, were identified. The vapor of (E)-2-hexenol is repellent to both sexes ofHotea adults and toxic to blowfly (Calliphora) eggs.

Chemical defense in larvae of the plant bugHotea gambiae has been investigated. Results of analyses (GC, GC-MS) on the secretions from the three dorsally situated larval abdominal defense (scent) glands are reported. The secretion from the first abdominal gland consists of a mixture of C10 and C15 isoprenoids: (C10) a-pinene, ß-pinene, limonene, ß-phellandrene; (C15) ß-caryophyllene, caryophyllene oxide, a-humulene, and (the major component) humulene epoxide II. The secretions from the second and third abdominal glands are similar mixtures consisting of (E)-2-decenal, (E)-4-oxohex-2-enal, andn-tridecane together with lesser amounts of (E)-2-hexenal,n-dodecane, and other materials. Isoprenoid defense is now known from four species of plant bugs (Heteroptera) associated with Malvaceae.

Previous studies have shown that secondary alkylsulphohydrolases from certain detergent-degrading micro-organisms are unusual esterases in that they catalyse fission of the C-O bond of the alkyl sulphate ester linkage. The position of bond fission catalysed by a primary alkylsulphatase and an arylsulphohydrolase present in Pseudomonas C12B has now been investigated. The primary alkylsulphatase behaved like the secondary alkylsulphohydrolases in cleaving the C-O bond of potassium heptan-1-yl sulphate. In contrast, the arylsulphohydrolase, in common with other similar enzymes previously studied, catalysed the fission of the O-S bond of potassium p-nitrophenyl sulphate.

The electron impact mass spectra of a series of natural anthraquinone, anthrone, dianthrone aglycones and their ‘O’ and ‘C’ linked glycosides have been studied. Electron impact mass spectrometry failed to provide molecular weight information for the dianthrone aglycones and for the ‘O’ linked glycosides. Ammonia chemical ionization and field desorption mass spectra were studied as techniques to overcome this deficiency. A combination of electron impact and field desorption mass spectrometry proved to be most effective for structural studies of the dianthrone aglycones and the ‘O’ linked glycosides.

By gas chromatography-mass spectrometry, 1H NMR , and synthesis of authentic standards, the secretion from the abdominal dorsal scent gland of male adults of Sphaerocoris annulus has been found to contain a mixture of C9aliphatic aldehydes: nonanal (3%), (Z)-4-nonenal (13%), (E)-4,8-nonadienal (23%) and (Z)-4,8-nonadienal (56%). A further component was tentatively iden­tified as 8-nonenal (5%).

The high resolution field desorption mass spectra of a number of glycosides are described. In all cases the spectra enabled molecular weights and elemental formulae to be established, and the presence of fragment ions due to cleavage of the sugar groups provides considerable assistance in the identification of sugar and aglycone moieties. The [M + 23Na]+ion was the base peak in the spectrum of the sodium salt of testosterone glucuronide, and the presence [M + 39K]+, [M + 41K]+and [M + 23Na]+ions in the spectra of other glycosides are attributed to the presence of their sodium or potassium salts as impurities.

The field ionization and electron impact mass spectra of eleven coumarins have been compared. In the field ion spectra the molecular ions were the base peaks and structurally diagnostic fragment ions formed by direct cleavage were present, whereas the molecular ions were weak in the electron impact spectra and fragment ions formed by rearrangement were dominant. Crude coumarin mixtures obtained from natural sources have been successfully examined using field ionization and gas chromatography + field ionization mass spectrometry.

This paper shows the use of a quadrupole time‐of‐flight mass spectrometer combined with a liquid chromatograph for the identification of trace impurities in a drug substance. LC/MS/MS data obtained on trace impurities using this instrument compare favourably with those previously obtained on triple quadrupole mass spectrometers and in addition the high resoltuion capabilities of the ToF analyser allow accurate mass measurement of the fragment ions to better than 5 ppm in most cases. © 1997 John Wiley & Sons, Ltd.

Environmental Health Criteria, 43 Chlordecone, 44 Mirex, 45 Camphechlor. Geneva: World Health Organization, 1984. ISBN 92-4-154183-0, 92-4-154184-9, 92-4-154185-7.Rural Project Management: a handbook for students and practitioners. By V. Austin. London: Batsford Academic and Educational Ltd. 1985. pp. 280. ISBN 0-7134-4416-9. Price £14.95 (hardback).Social Anthropology and Development Policy. Edited by R. Grillo and A. Rew. London: Tavistock Publications, 1985. 208 pages incl. Index. ISBN: 0-422-79620-4. Price £7.95 paperback.Insect Pest Control, with Special Reference to African Agriculture. By R. Kumar. London: Edward Arnold (Publishers) Ltd, 1984, pp. 298. ISBN 0-7131-8083-8. Price £9.95.Annual Review of Phytopathology. Volume 23. Edited by R. James Cook et al. Palo Alto, California: Annual Reviews Inc., 1985. ISBN 0-8243-1323-2. Price $27.00 (U.S.A.), $30.00 (elsewhere).Vegetables in the Tropics. By H. D. Tindall. London: MacMillan, 1983. ISBN 0-333-24266-1. Price £35.00 hardback, ISBN 0-333-24266-8, £16 paperback.Pesticide Application: Principles and Practice. Edited by P. T. Haskell. Oxford: Clarendon Press, 1985, pp. 494. ISBN 0-19-854542-8. Price £50.00.Indigenous Agricultural Revolution. By Paul Richards, London: Hutchinson, 1985, pp. 192. ISBN 0-09-161320-5.Principles of Weed Control In California. Edited by E. A. Kurtz and F. O. Colbert. P.O. Box 9335, Fresno, California, CA 93791: Thomson Publications, 1985, pp. 474. ISBN 0-913702-32-3. Price: $29.95 (hardback).Handbook for Agricultural Pilots, 4th Edition. By H. R. Quantick. London: Collins, 1985, pp. xvii + 265. ISBN 0-00-383141-8. Price £12.95.Review of Biological Control of Pests in the Commonwealth Caribbean and Bermuda up to 1982. Editor M. J. W. Cock. Commonwealth Institute of Biological Control, Technical Communication No. 9. pp. 244. Slough: Commonwealth Agricultural Bureaux, July 1985. ISBN 0-85198-550-5. Price CAB member countries £35.00, non-member countries US$52.50.Economic Guidelines for Crop Pest Control. By K. H. Reichelderfer, G. A. Carlson and G. A. Norton. Rome: FAO, Plant Production and Protection Paper 58, 1984, pp. 93. ISBN 92-5-102109-0.The Pyrethroid Insecticides. Edited by J. P. Leahey. London: Taylor and Francis, 1985, pp. xi + 440. ISBN 0-85066-283-4. Price £45.00 (hardback).Handbook of Seed Technology for Genebanks. By R. H. Ellis, T. D. Hong and E. H. Roberts. Volume I. Principles and Methodology, pp. 210. ISBN 92-9043-118-0. Volume II. Compendium of Specific Germination Information and Test Recommendations, pp. 667. ISBN 91-9043-119-9. Rome: International Board for Plant Genetic Resources, 1985.Advances in Soil Science, Volumes 2 & 3. Edited by B. A. Stewart. Berlin: Springer-Verlag, 1985 a & b, pp. 235 + ix & 217 + ix. Vol. 2. ISBN 0-387-96114-3. Price £39.50 hardback. Vol. 3. ISBN 0-387-96116-X. Price £44.50, hardback.Boophilus microplus, the Common Cattle Tick. By J. L. Nunez, M. E. Munoz-Cobenas and H. L. Moltedo. Berlin: Springer-Verlag, 1985 (1982), pp. 204, 92 figs. Trans. H. Baillie, C. Michelsohn & C. Paris. ISBN 3-540-15146-X. Price DM 196.

A series of truncated Herpes simplex virion peptides studied by fast atom bombardment mass spectrometry under high and low energy collision induced dissociation conditions showed preferential fragmentation of the aspartyl‐proline amide bond, compared to other peptide bonds. Electrospray ionization investigation proved that this favoured fragmentation can not be attributed to only the known proline effect, as a change from Asp to Asn in the peptide yielded an Asn‐Pro bond which was found to be stable under the same ionization conditions. This mass spectrometric behaviour is in good agreement with the observation that DP bonds are sensitive to acidic conditions. © 1998 John Wiley & Sons, Ltd.

Chemical Methods for the Control of Arthropod Vectors and Pests of Public Health Importance. Geneva, World Health Organisation, 1984., pp. vi + 108 Price Sw Fr 14No Tillage Crop Production in the Tropics. Edited by I. O. Akobundu and A. E. Deutsch. Proceedings of WAWSS/IWSS Symposium, Monrovia, Liberia, August 1981. Corrallis: International Plant Protection Center, Oregon State University, Corrallis, OR 97331, USA, 1983. IPPC Document 46-B-83.Aviation in Crop Protection, Pollution and Insect Control. By H. R. Quantick, London: Collins Professional and Technical Books, Wm Collins & Sons, 1985, pp. 428 ISBN 0-00-383049-7. Price: £25.00.Plant Microbiology. By R. Campbell. Edward Arnold, 1985, pp. iv + 191. ISBN 0-7131-2892-5. Price £8.50.Guidelines for Drinking Water Quality. Volume 2. Health Criteria and Other Supporting Information.World Health Organisation Geneva, 1984. ISBN 92-4-154169-5Advances in Soil Science. Volume 1. Edited by B. A. Stewart, Berlin: Springer-Verlag, 1985., pp. ix + 300. ISBN 3-540-96027-9. Price D.M. 128 (hardback).The Biology of Gall Insects. Edited by T. N. Ananth-akrishnan. Edward Arnold, March 1985, pp. xii + 362, ISBN 0-7131-2906-9. Price £30.00.Field Problems of Tropical Rice. (Revised edition) International Rice Research Institute 1983 pp. 172, ISBN 971-104-080-8A Farmer's Primer on Growing Rice. By Benito S. Vergara., International Rice Research Institute, 1979, pp.221.Lever-Operated Knapsack Sprayers By H. H. Fisher and A. E. Deutsch. Corvallis: International Plant Protection Center, or IPPC Document 53-A-84, 1985. pp. 32 US Library of Congress No. 83-082988.Tropical Plant Diseases. By H. David Thurston. Minnesota, The American Phytopathological Society, 1984, pp. 208. ISBN 0-89054-063-2. Price $12Essential Malariology (2nd Edition). By Leonard J. Bruce-Chwatt. William Heinemann Medical Books Ltd., March 1985, ISBN 0-433-04521-3. Price £22.50 (ELBS edition £7.50).1984 Crop Protection Handbook—Grass and Clover Swards. Edited by R. D. Williams, British Crop Protection Council, 2a Kidderminster Road, Croydon CR0 2UE. pp. 105. ISBN 0-901436-70-4. £15 (UK), (£19, Overseas post free).Management and Evaluation of Intercropping Systems with Cassava. By D. E. Leihner, Centro Internacional de Agricultura Tropical, Colombia. December 1983, pp. 70. ISBN 84-89206-32-5. List price $10.00 (various price reductions for developing countries)Pesticide Residues in Food-1983. FAO Plant Production and Protection Paper 61. Rome, Food and Agriculture Organization of the United Nations, 1985. ISBN 92-5-102222-4.Pesticides, 6th edition. Strasbourg, Council of Europe, 1984, pp. 12. Price £5.45Insect Management for Food Storage and Processing. Edited by Fred J. Baur. St. Paul: American Association of Cereal Chemists, 1985, pp. xiv + 384. ISBN 0-913250-38-4. Price $65 (AACC Members $45).Training and Visit Extension. By Daniel Benor and Michael Baxter. Washington, D.C.: The World Bank, 1984, pp. xii + 202. ISBN 0-8213-0121-7 Price £17.50. ( + £1.15 p. & p.)Potatoes for the Developing World, a Collaborative Experience. Lima: International Potato Center, 1984, pp. x + 148.

The use of ‘shift reagents’ in the determination of n.m.r. spectra, and of reductive alkylation in combination with g.l.c.–mass spectrometry, facilitates assignment of the order of substituents in porphyrins, and the application of these new techniques to isocoproporphyrin is described.

The authors report a patient with Alzheimer disease (AD) without encephalitis who was immunized with AN-1792 (an adjuvanted formulation of A-42). There were no amyloid plaques in the frontal cortex and abundant A-immunoreactive macrophages, but tangles and amyloid angiopathy were present. The white matter appeared normal and minimal lymphocytic infiltration in the leptomeninges was observed. This case illustrates the effects of an A-based immunization on AD pathogenesis in the absence of overt meningoencephalitis and leukoencephalopathy.

From the ventral abdominal gland VII-VIII in male adult Leptoglossus australis, five volatiles have been identified by GC and MS data in comparison with authentic standard materials. Benzyl alcohol (31%) and 2-phenyl ethanol (42%) together accounted for over 70% of the total scent. The remaining materials identified were 2-octenyl propionate (19%), (E,E′)-2,4-hexadienyl acetate (6%) and (E)-2-hexenol (2%).

Gentamicin sulphate employed in therapeutics consists of a mixture of three major aminoglycoside components, the gentamicins C1, C1aand C2. In the electron impact mass spectra of these components weak parent ions may be observed but they are of no diagnostic value in the commercial mixture. Chemical ionization and field desorption spectra of individual gentamicin components and commercial mixtures are reported and discussed. Isobutane chemical ionization spectra exhibit some fragmentation, but under optimum field desorption conditions little glycosidic cleavage is observed and [M + H]+ions dominate the spectra.

The electron impact, chemical ionization and field desorption mass spectra of seven steroids showing varying stability to electron impact have been compared.

For Abstract see ChemInform Abstract in Full Text.

Combined high‐performance liquid chromatography and electrospray mass spectrometry (LC/ES‐MS) has been used for direct characterisation of the polar membrane lipids in total lipid extracts from Halobacterium salinarium, a species of halophilic archaebacterium. The principle phospholipids found were the diphytanyl archaeol phosphatidylglycerol and diphytanyl archaeol phosphatidylglycerolphosphate methyl ester. The application of LC/ES‐MS revealed the additional presence of diphytanyl archaeol phosphatidylglycerol sulphate The extracts also contained an archaeol glycolipid, initially detected in preliminary offline ES‐MS studies, which was further characterised by LC/ES‐MS and by product ion tandem mass spectrometry (MS/MS) as a sulphate ester of diglycosyl‐2,3‐di‐O‐phytanyl‐sn‐glycerol. Whilst archaeol phospho‐ and glycolipids containing a (C20‐C20)‐isopranyl glycerol ether core predominated, LC/ES‐MS of the extracts from Halobacterium salinariumindicated the presence of an analogue containing one double bond in its isoprenyl ether core as a minor component of the phosphatidylglycerolphosphate methyl ester fraction, providing a further example of the previously recognised existence of isoprenologues of diphytanyl archaeols which occur as minor components of archaebacterial membrane lipids. The value of these techniques in compositional analysis of archaebacterial lipid extracts is discussed. Copyright © 2000 John Wiley & Sons, Ltd.

Combined high-performance liquid chromatography and electrospray mass spectrometry (LC/ES-MS) has been used for direct characterisation of the polar membrane lipids in total lipid extracts from Halobacterium salinarium, a species of halophilic archaebacterium. The principle phospholipids found were the diphytanyl archaeol phosphatidylglycerol and diphytanyl archaeol phosphatidylglycerolphosphate methyl ester. The application of LC/ES-MS revealed the additional presence of diphytanyl archaeol phosphatidylglycerol sulphate The extracts also contained an archaeol glycolipid, initially detected in preliminary offline ES-MS studies, which was further characterised by LC/ES-MS and by product ion tandem mass spectrometry (MS/MS) as a sulphate ester of diglycosyl-2,3-di-O-phytanyl-sn-glycerol. Whilst archaeol phospho- and glycolipids containing a (C20-C20)-isopranyl glycerol ether core predominated, LC/ES-MS of the extracts from Halobacterium salinarium indicated the presence of an analogue containing one double bond in its isoprenyl ether core as a minor component of the phosphatidylglycerolphosphate methyl ester fraction, providing a further example of the previously recognised existence of isoprenologues of diphytanyl archaeols which occur as minor components of archaebacterial membrane lipids. The value of these techniques in compositional analysis of archaebacterial lipid extracts is discussed. Copyright © 2000 John Wiley & Sons, Ltd.

The shield bugs, Apodiphus amygdali (Germar), were collected in Iraq (Baghdad, Sept. 24, 1973) and brought to us by Mr. M. S. Abdul Rassoul, of the Iraq Natural History Museum, to whom we express our thanks. The collection included several live nymphs and adults. The scents from these were collected after dissection and either analyzed immediately by gas chromatography (GC) or accumulated in acetone in sealed glass tubes for subsequent analysis by gas chromatography-mass spectrometry (GC-MS) (Games and Staddon 1973a).

The subfamily Triatominae of the family Reduviidae is composed of blood-sucking bugs of which several are of economic importance as vectors of the etiological agent of Chagas' disease in the Neotropical region. In one member of the subfamily, Rhodnius prolixus Stål, the main if not the only component of the defensive scent from Brindley's scent glands has been identified. It is iso-butyric acid (Pattenden and Staddon 1972). We have since carried out analyses of the scent collected from the Brindley's glands of Triatoma phyllosoma (Burmeister) and Panstrongylus megistus (Burmeister). The liquid scent was collected after dissection and stored in acetone in a sealed glass tube for subsequent analysis by gas chromatography-mass spectrometry (Games and Staddon 1973). The solution was injected at a temperature of 60°C and the analysis concluded at a temperature of 200°C. Two separate accumulations of scent from T. phyllosoma and one from P. megistus were analyzed. The chromatographic trace obtained from each sample revealed one peak only and the several spectra obtained through the course of peak development and decay were indistinguishable from each other and from that of an authentic sample of iso-butyric acid obtained under the same conditions of analysis. Possibly the production of iso-butyric acid by Brindley's glands is a characteristic of the subfamily Triatominae.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.