| Popis: |
Mass spectrometry, both stand alone and in conjunction with various separation science approaches, has been used for the qualitative and quantitative study of a number of systems of industrial interest. These systems include lubricant additives, organic acids, aliphatic amines and poly (ethylene) glycol oligomers. Organic acids and aliphatic amines are industrially important compounds. The acids in this study helped evaluate the capabilities and robustness of capillary electrophoresis (CE) with and without mass spectrometric detection. Transient capillary isotachophoresis (tCIP) was also examined as a pre-concentration technique. This allowed larger sample volumes to be injected on to the capillary and improved detection limits by a factor of 100. Production samples of organic acids were also successfully analysed by CE and CE-MS. Aliphatic amines, considered harmful, require trace level analysis due to regulatory legislation. CE and CE-MS methodologies were developed for them. The amines under analysis, not possessing UV active chromophores, were unamenable to conventional UV detection. Consequently an indirect-UV detection method was developed. Environmental samples from an amine plant were analysed by the methods developed. The quantitation of low mass poly (ethylene) glycol oligomers was examined by MALDI-TOF and APCI MS. The results were compared with those obtained by carbon-13 NMR. Attempts were made to obtain pure PEG200 and PEG300 oligomers by semi-preparative HPLC with fraction collection although subsequent characterisation gave mixed results. APCI-MS gave consistently lower average molecular weights than MALDI-TOF MS. |
