Simultaneous Quantitation of Methotrexate and its Metabolite 7-Hydroxymethotrexate in Human Plasma by LC/MS/MS Combined with Solid Phase Extraction

摘要

A LC-MS/MS method has been validated for the quantitation of methotrexate and 7-hydroxymethotrexate in lithium heparin human plasma from 1 to 500 ng/mL. The method is sensitive, selective, accurate, and reproducible. Methotrexate and 7-hydroxymethotrexate are stable for 20.5 hrs at room temperature, after 5 freeze/thaw cycles, and for at least 62 days at -20 deg C and -70 deg C.