LC-MS methodology

He then joined the Central Research Establishment of the Home Office Forensic Science Service (as it then was) at Aldermaston where he developed thermogravimetry-MS, pyrolysis-MS, GC-MS and LC-MS methodologies for the identification of analytes associated with crime investigations. It was here that his interest in LC-MS began with the use of an early moving-belt interface. This interest continued during periods of employment with two manufacturers of LC-MS equipment, namely Kratos and subsequently Interion, the UK arm of the Vestec Corporation of Houston, Texas, the company set up by Marvin Vestal, the primary developer of the thermospray LC-MS interface. 

Fichtner and Giese [16] include plasticisers in their brief review of the application of LC-MS methodology to the identification of extractables from polymer materials. 

The refinement or creation of new approaches may result in the elimination of existing activities. For example, the structure confirmation of newly synthesized lead compounds traditionally involved an extensive use of nuclear magnetic resonance (NMR). Once reliable LC/MS methodologies became available and their performance was benchmarked, they were soon accepted as an exclusive method for the rapid structure confirmation of lead compounds at an earlier stage of the lead identification process. 

Kleintop, B. Volk, K. Hail, M. Sanders, M. Reddick, C. Bolgar, M. Warrack, B. Liu, X Detlefsen, D. Kerns, E. Lee, M. 1998. Predictive degradation profiling of biomolecules using LC/MS methodologies. Proc. 46th ASMS Conf. Mass Spectrom. and Allied Topics (Orlando, Florida), 240. 

Most of the published analytical methods for the determination of antidepressants were developed in plasma, serum, whole blood, and urine, which are the most useful matrices for clinical and toxicological analysis of these therapeutic compounds. However, albeit few, some LC-MS methodologies have also been described for the analysis of several antidepressants in hair [30-33], oral fluid [34, 35], breast milk [36], or typical forensic matrices such as gastric content, bile, vitreous humor, brain, liver, lung, and/or muscle [37 10],... 

Analytical methods for TDM should cover therapeutic ranges, and LLOQ requirements are not as low as those for pharmacokinetic applications. LC-MS methodologies for the determination of one specific antidepressant could also be applied in these cases. However, as previously stated in this chapter, multianalyte procedures are preferable because they are simpler, faster, cheaper, and allow for the determination of several analytes using the same sample aliquot. Moreover, multianalyte procedures are not only useful, but also required in clinical or forensic applications, where the target antidepressant is initially unknown, and several of them could be involved in the intoxication. 

It is anticipated that LC/MS methodology will eventually be used to the exclusion of all other techniques for the analysis of pharmaceuticals. 

Methods for Determining Biomarkers of Exposure and Effect. Few methods exist for monitoring exposure to RDX. Methods have been reported for detection of the analyte in plasma (Army 1981a Fine et al. 1984 Turley and Brewster 1987 Woody et al. 1986), urine (Turley and Brewster 1987 Woody et ai. 1986), cerebrospinal fluid (Woody et al. 1986), feces (Woody et al. 1986), and tissues (Army 1981a), as well as on hands (Douse 1982 Fine et al. 1984 Lloyd 1983). The available methods can detect levels in urine and plasma from exposure to concentrations below those that would be encountered in most manufacturing situations. In general, these methods are reliable and accurate however, the development of the LC-MS methodology could be useful as a definitive method to validate the specificity of the HPLC methods. The data are insufficient to permit correlation of RDX levels in the urine or blood with exposure levels (see Section 2.5.1). Therefore, the level of RDX in urine or blood cannot be used as a biomarker of exposure. 

Alvi, K. A., Peterson, J., and Hofman, B. (1995) Rapid identification of elaiophylin and geldanamycm in Streptomyces fermentation broths using CPC coupled with a photodiode array detector and LC-MS methodologies. J Ind. Microb. 15, 80-84. 

The testing procedure widely used is the MBA and, specifically, a modified version of that published by the American Public Health Association (APHA) in 1985 [35,36]. ELISA and LC-MS methodologies have been developed to detect a wide range of brevetoxins and identified as alternative candidates to replace bioassay once fuUy validated [10]. 

LC-MS methodologies applying TSP interfacing for unequivocal identification of isomers, oligomers and homologues of surfactants and their biodegradation intermediates in environmental samples at trace levels have been reviewed [28] very extensively [23, 40]. 

Chromatography—Mass Spectrometry (LC—MS) Methodology for Metabolite Identification... 

The LC-MS approach is currently the most popular approach for lipid analysis [55-57], although it may not be the best choice for global lipid analysis (i.e., lipidomics). The rationale behind the LC-MS approaches is to maximally exploit the LC separation technology with the most sensitive detection power of MS currently available. Three major factors are generally considered for successful development of LC-MS methodology in lipidomics, as well as understanding the principles of those developments. 

Salicylic acid, An electrospray LC-MS methodology for monitoring the serum... 

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