New high-performance liquid chromatographic method for determination of clopidogrel in coated tablets.

A new high-performance liquid chromatographic method was developed and validated for clopidogrel determination in pharmaceutical formulations. The system consisted of an ACE 5 octadecylsilane (C18; 150 x 4.6 mm id), 5.0 microm particle size column; methanol-0.1% triethylamine (75 + 25, v/v), pH 5.3, mobile phase at a flow rate of 1.2 mL/min; and a diode array detector set at 220 nm. Specificity, linearity, precision, accuracy, and robustness were the parameters evaluated. The retention time for clopidogrel was 6.8 min. To estimate specificity, an aqueous sample solution was subjected to degradation by ultraviolet light and by acid, alkaline, and oxidation media. The peaks of degradation products did not interfere with the compound signal, and there was no interference when a placebo solution was analyzed. Linearity over a concentration range of 10.0 to 90.0 microg/mL was shown (correlation coefficient = 0.9998). Low values of relative standard deviation indicated the adequate intraday and interday precision. The average recovery was found as 99.16%. In the robustness test, small modifications to the mobile phase composition did not affect the determination of clopidogrel. The proposed method proved to be simple, fast, and cost efficient for the intended use.