ABSTRACT
The spectrophotometric multi-component analysis involves spectrum recording and mathematical equations. However, spectral interference poses a major limitation when mixture samples are encountered. To overcome this derivative spectrophotometry (DS) has been introduced for the resolution of overlapping peaks. In this review modified methods like derivative quotient spectra, double divisor ratio spectra derivative method, double divisor means centering of ratio spectra method, derivative subtraction coupled with the constant multiplication method (DS-CM), amplitude subtraction (AS), modified amplitude subtraction (MAS), amplitude factor method (P-Factor), amplitude modulation method (AM), amplitude summation method (A-Sum), simultaneous derivative ratio spectrophotometry (S1DD), derivative compensation ratio via regression equation, differential dual wavelength (D1 DWL), differential derivative ratio (D1DR), successive derivative subtraction method (SDS) and derivative transformation (DT) of derivative spectrophotometry theories and applications are reviewed. These methods were applied to solve different complex pharmaceuticals mixtures. These developed methods were simple and cost-effective.
ABSTRACT
Four sensitive and precise spectrophotometric methods were developed and validated for the simultaneous determination of pioglitazone hydrochloride (PGZ) and glimepiride (GLM) in their pharmaceutical formulations. Among the methods adopted were direct absorbance, firstderivative (1D), second-derivative (2D) and first-derivative of ratio spectra (1DD). The selectivity of the proposed methods was checked using laboratory prepared mixtures. The proposed methods were successfully applied to the analysis of GLM and PGZ in their mixture and in pharmaceutical dosage forms without interference from other additives.