Fig. 5.

ESI LC-MS/MS analysis of GSH conjugates of PEITC and PIC with precursor ions at m/z 455 generated by in the reconstituted system containing human CYP2E1. CYP2E1 was reconstituted with reductase and incubated with PEITC or PIC in the presence or absence of NADPH. GSH conjugates of PEITC were extracted and analyzed as described under Materials and Methods. (A) Extracted ion chromatogram at m/z 455 in the sample incubated with human CYP2E1 in the presence and absence of NADPH (top panel), and a chemical standard mixture of PIC and GSH in acetonitrile/water (bottom panel). (B) LC-MS/MS pattern of the ion with an m/z of 455 eluting at 14.9 minutes. (C) The proposed structure of the GSH conjugate of PIC.