Abstract: AIM: To develop a high performance liquid chromatography method for the determination of ibuprofen in human plasma,and to evaluate the bioequivalence of two preparations of ibuprofen.METHODS: Twenty-four healthy male volunteers were given a single or multiple oral dose of 300 mg sustained-release capsule of each preparation in a randomized two-way,crossover study.Serial plasma samples were analyzed by a high performance liquid chromatography method. Pharmacokinetic parameters were calculated and compared statistically to evaluate the bioequivalence between the two preparations by DAS 2.0 program.RESULTS: After orally a single dose (300 mg),the major pharmacokinetic parameters of the test and reference preparations were as follows:C_max were(12.7±5.4)and(13.5±5.9) μg/mL,t_max were(5.5±1.4)and (5.1±1.0) h,AUC_0→24 were(96.8±50.2) and(95.7±45.4) μg·h·mL^-1. After orally a multiple dose(300 mg),the major pharmacokinetic parameters of the test and reference preparations were as follows:t_max were(4.8±1.0)and (4.6±0.9) h,C_max were(14.1±5.3)and (14.9±6.4) μg/mL,C_av were(8.3±3.4)and(8.6±4.3) μg/mL,and DF were(117.2±35.3)% and (131.7±35.1)%. Main pharmacokinetic parameters between the two formulations in both single and multiples dose studies showed no statistical difference(P>0.05).CONCLUSION: The method was proved to be suitable for the determination of ibuprofen in human plasma. The result of the statistical analysis showed that two formulations of ibuprofen were bioequivalent.

Key words: ibuprofen, high performance liquid chromatography, bioequivalence, sustained-release capsules