Novel Spectrophotometric Estimation of Olanzepine Using Hydrotropic Solubilizing Agents

Ultraviolet absorption spectrophotometric method for the estimation of poorly water soluble drug like Olanzepine in pharmaceutical formulations has been developed. Aqueous solubility of this selected model drug was to a great extent (6 to 98 fold) in 1 M sodium benzoate, 1 M sodium acetate, 1 M sodium bicarbonate, 1M sodium chloride, 1 M sodium gluconate, 1M thiourea, 1M trisodium citrate and 1 M urea solutions. The primary objective of the present investigation was to employ these hydrotropic solutions to extract the drug from dosage forms, precluding the use of costlier organic solvents. The selected λmax for Olanzepine was 329.5 nm. The hydrotropic solutions used did not show any absorbance above 306 nm, and therefore, no interference in the estimation was seen. The results of analysis have been validated statistically, and by recovery studies. The proposed methods are new, simple, economic, accurate, safe and precise.