[Study on pharmacokinetics of lansoprozole in concentration of blood plasma healthy volunteers intravenous infusion by improved HPLC].

This work aimed to set up a high performance liquid chromatography (HPLC) method to determine the concentration of lansoprazole in human plasma and study the pharmacokinetic characters of lansoprazole in Chinese healthy volunteers after intravenous (IV) infusion. In accordance with double 3 x 3 Latin square design with self-crossover design, 12 volunteers were randomly divided into six groups, with half males and half females. The volunteers were administered with single dose of 15, 30, 60 mg of lansoprazole by IV infusion at a constant speed respectively, to study the clinical pharmacokinetics of lansoprazole. The linear range of lansoprazole in human plasma was 0.020-4.970 microg/ml (r = 0.9999); The intra-day and inter-day RSD were less than 10%. After receiving single doses of 15, 30 and 60 mg of lansoprazole, t(1/2) were (1.663 +/- 0.405) h, (1.541 +/- 0.339)h and (1.747 +/- 0.156) h; Cmax were (1.065 +/- 0.094) microg/ml, (2.104 +/- 0.312) microg/ml and (3.786 +/- 0.356) microg/ml; AUC(0-infinity) were (2.376 +/- 0. 432) microg x h/ ml, (4.722 +/- 0.753) microg x h/ml and (10.495 +/- 2.129) microg x h/ml respectively. The improved HPLC method is simple, rapid and reproducible. It could be used for determination of the concentration of lansoprazole in human plasma. The pharmacokinetics of lansoprazole for injection was found to fit the linear dynamics in vivo within the dose range of 15 to 60 mg. In addition, the results suggested that gender had no statistic significant effect on the pharmacokinetic process of lansoprazole after IV infusion of single dose.