High-performance liquid chromatography with electrochemical detection for analysis of gliclazide in plasma

A sensitive HPLC–electrochemical detection method was developed for the analysis of gliclazide (GL) in human plasma. After deproteination of 100 μL of plasma by acetonitrile, evaporation, and reconstitution, GL was separated on a C18 column (150 mm × 4.6 mm) by the mobile phase (70 mM disodium tetraborate, pH 7.5, containing 26.5% of acetonitrile). The regression equations were linear (r > 0.9990) over the range of 50 nM to 4.00 μM. The precision and accuracy of intra- and inter-day analysis were less than 5.3 and 0.93% for relative standard deviation and relative error, respectively. The limit of detection for plasma was 10 nM for GL (S/N = 3, 10 μL injection). This newly developed method was applied for monitoring blood levels with one healthy volunteer dosing with a GL tablet.