Tandem Evolved Gas–Gas Chromatography–Mass Spectrometry

Evolved gas analysis–mass spectrometry (EGA-MS) and pyrolysis–gas chromatography–mass spectrometry (Py-GC-MS) are powerful and complementary analytical techniques for characterization of insoluble materials. A Frontier multishot pyrolyzer interfaced with a GC-MS allows for both EGA-MS and Py-GC-MS experimental modes with a single instrument. In addition, the small sample mass (micrograms) and highly reproducible pyrograms of the Frontier pyrolyzer makes it desirable instrumentation for product verification and forensic applications. Unfortunately, incompatibilities between EGA-MS and Py-GC-MS experimental setups require two separate experiments, which has several disadvantages: (1) significant instrument downtime when switching between modes, which is due to changing internal columns; (2) reduction of the column’s life span from repeated exposure to atmosphere and constant trimming of the column; (3) twice the amount of sample is required, and (4) potential disconnect between EGA-MS and Py-GC-MS results arising from sample-to-sample variability. This work details modifications to a Frontier multishot pyrolyzer and Agilent GC-MS instrumentation that allows for tandem EGA-MS and Py-GC-MS (EGGC-MS, “EGG”) analysis of a single sample and resolves the mentioned disadvantages.