Spectrophotometric Determination of Pregabalin Using Gibb’s and MBTH reagent in Pharmaceutical Dosage Form
By K. Sowjanya, J.C. Thejaswini, B.M. Gurupadayya and M. Indupriya
Two simple, extractions free spectrophotometric methods (Method 1 and 2) for the quantitative estimation of Pregabalin (PGB) in bulk drugs and pharmaceutical formulations (capsules) have been developed. Method 1 is based on the formation of a colored oxidative coupling product between 2, 6-dichloroquinone chlorimide and the drug. Colored product at its λmax 400 nm shows linearity in the concentration range of 50-350µg/ml. Second method is based on reaction of oxidative coupling of Pregabalin with 3-methyl-2-benzthiazolinone hydrazone (MBTH) to form green colored product. Colored product of λmax 668 nm shows linearity in the concentration range of 50-350 µg/ml.The relative standard deviations for first method is 0.36% and for second method is 0.35% were obtained. Linear relationships with good correlation coefficients (0.998-0.999) were found between absorbance and the corresponding concentrations of the drug. The reliability and performance of the proposed methods was validated statistically. The percentage recovery ranged from 100.42% and 99.69% respectively.
Keywords: Spectrophotometric, Pregabalin, oxidative coupling, 2, 6-Dichloroquinone-4-chloroimide (gibb’s), 3-methyl-2-benzthiazolinone hydrazone (MBTH).