Simultaneous determination of 1-chloro-2,4-dinitrobenzene, 2,4-dinitrophenyl-S-glutathione and its metabolites for human placental disposition studies by high-performance liquid chromatography

We developed and validated an HPLC method for determination of 1-chloro-2,4-dinitrobenzene (CDNB) and its glutathione conjugate 2,4-dinitrophenyl-S-glutathione (DNP-SG) to study the kinetics and mechanisms involved in DNP-SG formation and efflux, as a probe for human placental metabolism and transport. This method combines use of 3 μm solid phase, rapid mobile phase gradient with dual wavelength ultraviolet detection to permit determination of a lipophilic parent compound and its hydrophilic metabolites in a single short run. The selectivity, linearity, accuracy, precision, relative recovery and stability of the assay are sufficient for determining CDNB, DNP-SG and its metabolites from buffer and tissue samples to support placental drug metabolism and transport studies.