Comparative Evaluation of GC/MS (Gas Chromatography/Mass Spectrometry) Data Analysis Processing

摘要

Mass spectra obtained by fused silica capillary gas chromatography/mass spectrometry/data system (GC/MS/DS) analysis of mixtures of organic chemicals adsorbed on Tenax GC cartridges was subjected to manual and automated interpretative techniques. Synthetic mixtures (85 chemicals representing 15 chemical classes) were prepared to simulate the following design effects: (1) the occurrence of similar or dissimilar overlapping mass spectra from two or more constituents present in unresolved gas chromatographic peaks; (2) the occurrence of similar and dissimilar proportions (concentrations) of unresolved components in gas chromatographic peaks; and (3) the presence of different chemical classes in a mixture. Environmental samples from seven different geographical areas in the Continental U.S. were collected and analyzed. Using synthetic mixtures the interpretative methods evaluated for accuracy were: (1) manual (skilled interpretor); (2) Incos data software; (3) Mass Spectra Fourier Transformed/Search software; and (4) an RTI Mass Spectral Search System. A Rindfleisch deconvolution program was also applied to raw data prior to using the automated procedures. Only manual, Incos, and the RTI system were evaluated with environmental samples. The deconvolution program was also part of this evaluation.