Abstract

EVALUATION OF LAWSONE AS AN ANALYTICAL REAGENT FOR COLORIMETRIC ESTIMATION OF ACTIVE PHARMACEUTICAL INGREDIENTS

Pooja D. Dhruv* and Dr. Parula B. Patel

ABSTRACT

The aim of the present work is to estimate various API having different functional groups using Lawsone as a derivatizing agent. As lawsone is used in various herbal formulations as a hair colouring agent, hence it can be established as a tool to develop the analytical methods for estimation of various drugs. Numerous formulations in the market are available with API’s having no absorbance in the visible region (400-800 nm). Estimation of some of them is made possible in visible region by reacting it with Lawsone in different experimental conditions. Hence, we can estimate the drugs that are devoid of chromophores using Lawsone reagent. Simple colorimetric method is used for estimation and the method is clear, precise and cheap. We applied lawsone as a derivatizing agent for derivatization of different pharmaceuticals, which was used for the estimation of them. Linearity was taken after derivatization with Lawsone and absorbance was measured at 482 nm for Sulphanilamide, 496 nm for Ramipril, 433 nm for Vanillin, 453 nm for Diclofenac, 455 nm for Glycine, 435 nm for Dextrose, 455 nm for L-Glutathione reduced, 454 nm for Metformin. Validation of developed methods was performed according to ICH Q2R1guideline.

Keywords: Active Pharmaceutical Ingredient (API), Lawsone, Derivatizing agent, Colorimetric method.