Differential pulse voltammetric simultaneous determination of four anti-inflammatory drugs by using soft modelling

An application of a partial least squares calibration method for the simultaneous voltammetric determination of indomethacin, acemethacin, piroxicam and tenoxicam is suggested. It was shown that it is possible to resolve complex mixtures of analytes even when they have strongly overlapped signals. In order to check the proposed method, statistical analysis of the results was performed by mean of hypothesis tests. The method developed was applied to the electrochemical reduction region of four anti-inflammatory drugs and allowed the drugs to be quantified at concentrations between 0.52 and 4.09 mug mL(-1) for acemethacin, 0.44 and 3.50 mug mL(-1) for indomethacin, 0.43 and 3.40 mug mL(-1) for piroxicam, and 0.42 and 3.30 mug mL(-1) for tenoxicam with good results. The average absolute value of relative errors was 2.25%, 4.31%, 1.68% and 2.49%, respectively.