Abstract

GC/HRSIR as a complementary technique to GC/ECNIMS

Author(s): William C.Brumley

Gas chromatography/electron capture negative ion mass spectrometry (GC/ECNIMS) is a highly selective and sensitive technique for the analysis of appropriate analytes in complex matrices. Its major drawback is often the lack of fragmentation indicative of structure that can be used to confirmthe identity of the analyte. Recourse to lowresolution EI selected ion recording (SIR) at low resolution can be tried to validate the methodology with additional specificity, but then the selectivity loss relative to ECNIMS and the presence of complex matrix interferences may require additional cleanup that was not needed for GC/ECNIMS. One solution is to use high resolution mass spectrometry as GC/HRSIR to provide the selectivity, sensitivity, and specificity needed to validate the GC/ECNIMS method that will be used for the bulk of the analyses by providing the needed specificity. Several examples are given as to howwell thisworks in practice.