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Chemical analysis for the characterisation of micro-organisms is rapidly evolving, after the recent advent of new ionisation methods in mass spectrometry: electrospray (ES) and matrix-assisted laser desorption/ionisation (MALDI). These methods allow quick characterisation of micro-organisms, either directly or after minimum sample preparation. This report provides a brief introduction to ES and MALDI mass spectrometry and a discussion of micro-organism characterisation capabilities. Some attention is devoted to the analysis of mixtures of proteins, lipids and other compounds, to the combination of polymerase chain reaction technology and mass spectrometry, and to the analysis of whole bacteria and their lysates. The review of results produced hitherto is concluded with an outlook on future developments.

The development of a procedure for the recording of reference mass spectra of trimethylsilyl (TMS) esters of alkyl and cycloalkyl methylphosphonates is described. The compounds are prepared in situ, on a small scale, from methylphosphonic difluoride and a selected alcohol dissolved in acetonitrile. Hydrolysis of the formed alkyl and cycloalkyl methylphosphonofluoridates to the corresponding methylphosphonates, evaporation to dryness and trimethylsilylation of the residue produces the TMS esters. The resultant reaction mixture is analysed by gas chromatography-mass spectrometry. In this way, electron impact mass spectra of TMS esters of 17 alkyl (ranging from butyl to nonyl) methylphosphonates and five cycloalkyl methylphosphonates were recorded. The mass spectra and a short description of the fragmentation processes of the TMS esters are presented., Text in English.