Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636063
Title: Development of a new interface for supercritical fluid chromatography/mass spectrometry and studies of photochromic compounds by supercritical fluid extraction, supercritical fluid chromatography and supercritical fluid chromatography/mass spectrometry
Author: Beaman, J. V.
Awarding Body: University College of Swansea
Current Institution: Swansea University
Date of Award: 1994
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Abstract:
The commercial applications and types of photochromic are many and varied. In this work spiroxazines, spiropyrans and fulgides, of the type used in optical lenses, were examined using a variety of analytic techniques. Initially the feasibility of using supercritical fluid extraction (SFE) for the extraction of photochromics, and some UV stabilisers, from lens matrices was investigated for the first time. Packed column supercritical fluid chromatography combined with mass spectrometry (pSFC/MS), using both a moving belt and a thermospray interface, was assessed as a method for the separation and analysis of standard photochromics, prior to analysis of unknown photochromic lens extracts. Standard mixtures of the photochromics were successfully separated by pSFC and the mass spectrometric fragmentation patterns were recorded. The unknown photochromics, extracted by SFE, were separated by pSFC and their structures were then suggested from the mass spectra. A preliminary investigation was also carried out into the use of electrospray/mass spectrometry for the analysis of standard photochromics and also a nickel quencher (UV stabiliser). The lens extracts were also analysed by GC/MS and GC/Fourier-transform infrared, which were found to be complementary analytical techniques to pSFC/MS. Part of the work in this thesis concerned the development of a liquid chromatography/mass spectrometry particle beam interface for use with pSFC/MS. After physical adjustment of the interface, the operating parameters and sensitivity of the technique were investigated. pSFC/MS with the particle beam interface was then successfully used for the first time for the separation and analysis of standard mixtures of tocopherols, estrogens and benzodiazepines. Timbo powder (Derris root) was then extracted by SFE and the resulting extract was analysed using the developed technique.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.636063  DOI: Not available
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