Atmospheric pressure ionisation-mass

ATMOSPHERIC PRESSURE IONISATION MASS SPECTROMETRY—I. GENERAL ASPECTS... 

Whilst these methods are informative for the characterisation of synthetic mixtures, the information gained and the nature of these techniques precludes their use in routine quantitative analysis of environmental samples, which requires methods amenable to the direct introduction of aqueous samples and in particular selective and sensitive detection. Conventionally, online separation techniques coupled to mass spectrometric detection are used for this, namely gas (GC) and liquid chromatography (LC). As a technique for agrochemical and environmental analyses, high performance liquid chromatography (HPLC) coupled to atmospheric pressure ionisation-mass spectrometry (API-MS) is extremely attractive, with the ability to analyse relatively polar compounds and provide detection to very low levels. 

Atmospheric pressure ionisation-mass spectrometric characterisation of silicone surfactants... 

Quantitative analysis by atmospheric pressure ionisation-mass spectrometry... 

ATMOSPHERIC PRESSURE IONISATION MASS SPECTROMETRY—VI. NON-IONIC SURFACTANTS LC-MS OF OTHER NON-IONIC SURFACTANTS... 

Owing to the anionic character of LAS, an electrospray ionisation (ESI) interface operated in negative ion mode is particularly attractive for the mass spectrometric detection of this surfactant type. Consequently, a great part of the atmospheric pressure ionisation-mass spectrometry (API-MS) work on LAS is devoted to the application of (— )-ESI-MS. 

ATMOSPHERIC PRESSURE IONISATION MASS SPECTROMETRY—X. LC—MS OF AMPHOTERIC SURFACTANTS... 

White, S., Catterick, T., Fairman, B. and Webb, K. (1998) Speciation of organo-tin compounds using liquid chromatography atmospheric pressure ionisation mass spectrometry and liquid chromatography inductively coupled plasma mass spectrometry as complementary techniques./. Chromatogr. A, 794, 211-218. 

Sjoberg, J.R. Markides, K.E. Capillary Column Supercritical Fluid Chromatography-Atmospheric Pressure Ionisation Mass Spectrometry Interface Performance of Atmospheric Pressure Chemical Ionisation and Electrospray Ionisation,", 7. Chromatogr. A 855, 317-327 (1999). 

Sjoberg, P.J. and Markides, K.E., Capillary column supercritical fluid chromatography-atmospheric pressure ionisation mass spectrometry interface performance of atmospheric pressure chemical ionisation and electrospray ionisation, J. Chromatogr. A, 855(1), 317, 1999. 

Imoto et al. by high performance liquid chromatography combined with atmospheric pressure ionisation mass spectrometry (API-MS). The crude saponin isolated from the leaves was chromatographed on octadecyl silica column and eluted with an aqueous methanol solution containing ammonium acetate. The fractions thus separated were directly introduced into an atmospheric pressure ionisation mass spectrometer connected with the liquid chromatograph by an interface consisting of a nebulizer and a vaporizer through a PTFE tube (Hitachi, Japan). The vaporized sample and solvent molecules at 300°C were introduced into the ion source of the atmospheric pressure ionisation system. 

Zhou, S. and Hamburger, M. (1996) Application of liquid chromatography-atmospheric pressure ionisation mass spectrometry in natural product analysis, evaluation and optimization of electrospray and heated nebulizer interfaces. J Chromatogr. A 755, 189—204. 

Seubert, A. Schminke, G. Nowack, M. Ahter, W. Buchberger, W. Comparison of on-line couphng of ion-chromatography with atmosphere pressure ionisation mass spectrometry and with inductively coupled plasma mass spectrometry as tools for the ultra-trace analysis of bromate in surface water samples. J. Chromatogr. 2000,884, 191-196. EC contract SMT4-CT96-2134, EUR report, European Commission, No. 1960, ISBN 92-828-9401-0 Brussels. 2000. 

A final example of separation of dialkyldimethylammonium quaternaries on a column of 5 micron PLRP-S with a mobile phase of 5mM methanesulphonic acid in 70% acetonitrile is given in [34]. This example uses post-column ion suppression (see section 9.5.1) and atmospheric pressure ionisation mass spectrometry for component identification. Also described in this paper is the analysis of alkyl sulphates and alkane sulphonates. 

Ahrer, W. and Buchberger, W., Analysis of low-molecular-mass inorganic and organic anions by ion-chromatography-atmospheric pressure ionisation mass spectrometry, /. Chromatogr. A, 854, 275,1999. 

J Sunner, G Nicol, P Kebarle. Factors determining relative sensitivity of analytes in positive mode atmospheric pressure ionisation mass spectrometry. Anal Chem 60 1300-1307, 1988. 

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