QUANTITATIVE MULTICOMPONENT ANALYSIS OF ASPIRIN AND SALICYLIC-ACID IN TABLETS WITHOUT SEPARATION OF EXCIPIENTS BY MEANS OF PRINCIPAL COMPONENT REGRESSION AND A CLASSICAL LEAST-SQUARES ALGORITHM

Two multicomponent UV spectrophotometric methods utilizing principal component regression (PCR)and a classical least squares algorithm (CLS) have been compared for the simultaneous analysis of aspirin (ASA) and salicylic acid (SA) in pharmaceutical tablet preparations. The UV spectra were recorded from turbid solutions without separation of interfering excipients. The methods were applied to laboratory mixtures and commercial tablet formulations containing ASA and SA. The multicomponent methods were equivalent for accuracy and precision. The results of both methods were comparable to those from a conventional high-performance liquid chromatographic method.