ABSTRACT:
The simultaneous analysis of pharmaceutical mixtures by classical spectrophotometric methods without prior separation is a challenge owing to the strong overlapping of their zero order spectra (low selectivity). Hence, several techniques have been developed for solving this problem, such as derivative spectrophotometry. The aim of this study was to develop a simple, fast, accurate, precise, economical, and eco-friendly derivative spectrophotometric method for the quantitative determination of a binary mixture of amoxicillin (Amox) and clavulanic acid (Clav) without prior separation steps. The developed method is based on the use of first derivative spectra resulting from derivatisation of zero order, with using these parameters (d??=4 and scaling factor=15). The measurements were achieved by using zero-crossing technique (??= 278.5nm for Amox and ??= 228.3nm for Clav), which eliminated the overlapping caused by two drugs and excipients of tablets. The method showed significant linearity in the range (5 45µg/ml with =0.9998) and (1 - 10µg/ml with =0.9986) for Amox and Clav, respectively. The developed technique was validated according to the ICH guidelines. The method was successfully utilized for the simultaneous determination of Amox and Clav in the formulation. The obtained results were statistically compared with the reported method (HPLC) by applying t-test and F-value at 95% confidence level. No significant difference was observed regarding accuracy and precision. Hence,the proposed procedure can be utilized for regular quality control studies as alternative to chromatographic techniques.