Olorimetric determination of tiaprofenic acid using 2,4 dinitrophenylhydrazine

Three simple and sensitive spectrophotometric methods were described for the determination of tiaprofenic acid. The first depends on the reaction of tiaprofenic acid with 2, 4-dinitrophenylhydrazine and measuring the formed hydrazone spectrophotometrically at 391 nm in ethanolic solution. The second and third methods involved the treatment of the formed hydrazone with each of potassium cyanide and sodium hydroxide to give colored reaction products measurable at 409 and 509 nm, respectively. Optimization of the different experimental conditions was described and the developed methods were successfully applied to the analysis of tiaprofenic acid in dosage forms

Uv-derivative spectrophotometry in analysis of drug products containing rutin and ascorbic acid mixture

A simple and sensitive procedure for determining the binary mixture of rutin and ascorbic acid using first-derivative spectrophotometry is described. The procedure does not require any pre-separation step, and it is carried out in ethanolic aluminum chloride [1% w/v]. This procedure is valid in the range of 2.5 to 12.5 mug/ml of rutin and 5 to 25 mug/ml of ascorbic acid, the validity was checked by statistical analysis. The method has been applied in the determination of both drugs in commercially available pharmaceuticals [tablets and soft gelatin capsules]

Determination of indomethacin in the presence of its alkaline-induced degradation products using first-derivative spectrophotometry

A rapid and direct method for the determination of indomethacin in the presence of its alkaline induced degradation products using first- derivative spectrophotometry is presented. By measuring the absolute value of the first derivative curve at the zero contribution of the degradation products [1D 340 nm], the concentration of the intact drug can be calculated directly without interference of the degradation products. Beer's law was obeyed, for intact indomethacin, in range of 2-12 mg%. The method was proved using two sets of synthetic mixtures of the intact drug with its degradation products. The mean percentage recovery was 100.2 + ' 0.86 and 99.9 =0.74, respectively. The producer is simple, rapid and allows for accurate and precise results