Two simple and sensitive extractive visible spectrophotometric methods (M1 and M2) for the determination of tiaprofenic acid in pure and dosage forms based on the formation of colored chloroform soluble ion-association associates under specified experimental conditions are described. Two basic dyes namely methylene blue (MB, method M1) and safranin-O (SAF-O, method M2) are utilized. The extracts of the ion-associates exhibit absorption maxima at 650nm and 520nm for methods M1 and M2 respectively. Regression analysis of Beer-Lambert plots showed good correlation in the concentration ranges 8-24 µg/ml for method M1 and 8-40 µg/ml for method M2.The proposed methods are applied to commercial available tablets and the results are statistically compared with those obtained by the UV reference method and validated by recovery studies. The results are found satisfactory and reproducible. These methods are applied successfully for the estimation of the tiaprofenic acid in the presence of other ingredients that are usually present in dosage forms. These methods offer the advantages of rapidity, simplicity and sensitivity and normal cost and can be easily applied to resource-poor settings without the need for expensive instrumentation and reagents.
K. Raghubabu, Dr. Madhu Mohan N., Kalyanaramu, B., Rao, M. N., and Ramdas, C., “Simple and Economical Visible Spectrophotometric Methods Development for Determination of Tiaprofenic Acid From its Solid Dosage Forms Based on Ion Association Complex Formation”, Tablet, vol. 1, pp. 197–46, 2012.