Establishment of HPLC method for determination of SN38-PA and SN38 in rat plasma / 国际药学研究杂志

ABSTRACT

Objective To develop an HPLC method for the simultaneous determination of 7-ethyl-10-hydroxycamptothecin-10-palmitic acid ester(SN38-PA)and its active metabolite 7-ethyl-10-hydroxycamptothecin(SN38)in rat plasma. Methods The inter standard was 10-hydroxycamptothecin. The protein in plasma was precipitated with methanol after acidification with formic acid. SN38-PA and SN38 were separated on Agilent C18 column(4.6 mm×250 mm,5μm) with gradient elution by using the mobile phase of methanol-0.2% formic acid solution. The flow rate was 1 ml/min. The detection wavelength was set at 372 nm. The column temperature was maintained at 30℃. Results The linear ranges for SN38-PA and SN38 were 0.25-62.5(r=0.9998) and 0.05-12.5 μg/ml (r=0.9997) respectively. The limits of quantification were 0.18 and 0.04 μg/ml, respectively. The average relative recovery of SN38-PA and SN38 were 95.89% and 97.03%. The average absolutely recovery of SN38-PA and SN38 were 99.54% and 99.84%. The RSD for intra-day and inter-day were both less than 3%. Conclusion The method is fast, convenient, accurate and sensitive, so it can be used for determination of SN38-PA and SN38 in vivo.