RP-HPLC in determination of plasma nonoxynol-9 level in New Zealand rabbit and its application in pharmacokinetic study

Abstract

Objective:To establish a RP-HPLC method for determining the plasma concentration of nonoxynol-9 and to apply the method in studying the pharmacokinetics of nonoxynol-9 in healthy female rabbits.Methods:A single dose of nonoxynol-9(64 mg to each animal) was given to 6 healthy female rabbits(weighing 2.0-2.2 kg) via vagina.The plasma samples were collected and the concentrations of nonoxynol-9 were determined by RP-HPLC method using DiamonsilTM ODS column(200 mm×4.6 mm,5 μm) and mobile phase of methanol-water(955) at a flow rate of 1.0 ml/min.The excitation and emission wavelengths were 226 nm and 300 nm,respectively.The column temperature was 30℃.The pharmacokinetic parameters were calculated.Results:The calibration curve of nonoxynol-9 showed good linearity over the range of 0.05-5.00 μg/ml;both the intra-and inter-day precisions were lower than 10%.The recovery rates at three concentrations(0.10,0.50,and 2.00 μg/ml) were(101.67±8.12)%,(100.84±5.42)%,and(100.29±3.81)%,respectively.The main pharmacokinetic parameters of nonoxynol-9 were as following:t1/2(3.75±0.87) h,tmax(3.2±0.4) h,Cmax(2.75±0.32) μg/ml,AUC0-12(12.72±2.14) μg·h·ml-1,AUC0-∞(15.05±2.84)μg·h·ml-1,and MRT(6.85±1.13) h.Conclusion:The established method is convenient,sensitive and specific,and can be used for determination of plasma nonoxynol-9 concentration and for its pharmacokinetic studies in rabbits.