ABSTRACT
OBJECTIVE: To establish an HPLC method for determing irinotecan (CPT-11) and its metabolite 7-ethyl-10 HCPT in rat liver microsome incubation system, and to optimize the incubation conditions. METHODS: CPT-11and SN-38 were determined by HPLC. Single factor design was used to optimize the incubation conditions. RESULTS: The linear range of CPT-11 and 7-ethyl-10 HCPT in rat liver microsome incubation system were 20-4000 ng · mL-1 and 2-400 ng · mL-1, respectively. The optimal incubation conditions were as follows: 10 μmol · L-1 CPT-11, 0.02 mg liver microsomes and incubation for 15 min. CONCLUSION: The HPLC method is accurate and suitable for the determination of CPT-11and 7-ethyl-10 HCPT in rat liver microsomes. The incubation condition can be applied in drug interaction studies of irinotecan.