HPLC assay for determination of rebamipide in plasma and its pharmacokinetic investigation

OBJECTIVE: To establish a HPLC method for the determination of rebamipide in human plasma and investigate the pharmacokinetic characteristics of rebamipide in healthy volunteers after a singal oral dose. METHODS: The drug was extracted from plasma with ethyl acetate after acid purification, and then detected by UV detector at 230 nm with a mobile phase consisting of methanol:phosphate buffer (52:48). The data obtained were fitted with 3P87 program on computer. RESULT: A linear relationship was obtained between the peak height and the concentration of rebamipide from 20 μg·L-1 to 2200 μg·L-1 and the limit of detection was 10 μg·L-1. The average relative deviations (RSD) of within day and between day variation were 1.11~3.72% and 3.87~7.60% (n = 5) respectively. The recoveries of rebamipide were 99.48~100.20%. The results showed that the plasma concentration-time curve of the two preparations were all fitted to a one-compartment model with first order absorption and elimination. T peak of domestic and imported tablets were 1.95 ± 0.73 and 1.57 ± 0.55 h; c(max) were 510.8 ± 152.0 and 564.8 ± 187.7 μg·L-1; t(1/2) were 1.75 ± 0.63 and 1.66 ± 0.31 h; respectively. CONCLUSION: This experiment established a simple, highly sensitive and selective method for the determination of plasma rebamipide levels in humans. It provides a suitable analysis method for its pharmacokinetic studies.