Concentration Determination of Irinotecan and Its Active Metabolite in Human Plasma by HPLC-FLD / 中国药房

ABSTRACT

OBJECTIVE:To develop a method for simultaneous determination of irinotecan(CPT-11)and its active metabo-lite 7-ethyl-10-hydroxycamptothecin(SN-38)in human plasma.METHODS:After precipitated by acetonitrile and acidified with hy-drochloric acid,using camptothecin as internal standard,the plasma sample was determined by HPLC-FLD. The determination was performed on Waters Luna C18column with mobile phase consisted of 0.05 mol/L sodium dihydrogen phosphate-acetonitrile(7030, V/V,adjusted pH to 4.0 by phosphoric acid)at flow rate of 1 mL/min. The excitation wavelength was set at 380 nm;the emis-sion wavelengths of CPT-11 and SN-38 were set at 480 nm and 535 nm,respectively. The column temperature was 25 ℃ and the sample size was 20 μL. RESULTS:The linear ranges were 200-1 000 ng/mL for CPT-11(r=0.999 4,n=5)and 5-45 ng/mL for SN-38(r=0.999 2,n=5). RSDs of inter-day and intra-day were 1.68%-5.57%. The relative recoveries of CPT-11 and SN-38 were 90.12%-106.93%(RSD<8%,n=5)and 92.07%-102.56%(RSD<6%,n=5);the extraction recoveries of CPT-11 and SN-38 were 72.23%-86.56%(RSD<6%,n=5)and 71.98%-83.44%(RSD<7%,n=5),respectively. The plasma concentra-tions of CPT-11 and SN-38 in 5 patients with colon cancer were 431.13-617.19,13.97-31.89 ng/mL(1 h after intravenous drip-ping)and 398.14-584.43,11.61-29.94 ng/mL(2 h after intravenous dripping). CONCLUSIONS:The method is simple,rapid, sensitive,reproducible and suitable for the determination of plasma concentration and pharmacokinetic study of CPT-11 and its metabolite SN-38.