OBJECTIVE:To develop a rapid RP-HPLC quantitative determination of lamivudine(LAM) in mouse serum and tissue homogenates METHODS:0 1ml of serum of tissue homogenates and 0 5ml of methanol were vortexed in a plastic tube for 30s and the mixture was then centrifuged at 15 000r/min for 10min 20?l of the resulting supernatant was directly injected and LAM was chromatographed on a reversed-phase Kromasil C column(150mm?4 6mm,5?m) using a mixture of phosphate buffer(pH6 8)and methanol(91∶9,v/v)and monitored at 270nm RESULTS:The standard curves were linear over a range from 0 25?g/ml to 50?g/ml The minimal detectable drug concentration was 60ng/ml(S/N=3) The average extraction recovery of LAM was more than 88% The average methodological recoveries of LAM ranged from 97% to 100% The within-dayand between-day precisions were less than 10% CONCLUSION:The assay is economic,simple,rapid and specific