Abstract: AIM: To establish an HPLC method for determination of metadoxine in human serum and to study the pharmacokinetics of metadoxine in healthy Chinese volunteers.METHODS: The volunteer serum samples were deproteinized and separated on a Diamonsil C₁₈ column (250 mm ×4.6 mm, 5 μm), eluted with the mobile phase of methanol-5 mmol·L ^-1 ammonium acetate (14:86, v/v) at a flow rate of 1.0 ml·min ^-1 and detected at 286 nm.RESULTS: The linear range of the calibration curve for metadoxine was 0.2 ～ 12 μg·ml ^-1, and the low limit of quantitation (LLOQ) was 0.2 μg·ml ^-1.The absolute and relative recoveries were 73.31 %～ 82.00 % and 91.08 %～ 95.69 % respectively.Within-day RSD and between-day RSD were less than 6.3 % and 4.3 %.CONCLUSION: The assay method is simple, sensitive, accurate, and reproducible and was successfully applied for the pharmacokinetic study of metadoxine in healthy volunteers.

Key words: metadoxine, HPLC, pharmacokinetics