A partial least-squares multivariate calibration method for the simultaneous spectrophotometric determination of spironolactone, canrenone and hydrochlorothiazide

An application of a partial least squares calibration method for the simultaneous spectrophotometric determination of spironolactone, canrenone and hydrochlorothiazide is suggested. The use of the PLS for the multicomponent spectrophotometric determination is demonstrated on the analysis of several synthetic mixtures. It was shown that is possible to resolve complex mixtures of analytes even when they have strongly overlapped signals. In order to check the proposed method a statistical analysis of the results was performed. The developed method was applied to the 232-370 nm region of the absorption spectra for the analytes and allowed the three substances to be quantified at concentrations between 2.0 and 15.0 mu g.ml(-1) with good results.