Utility of certain spectrofluorimetric methods for analysis of two pharmaceutical binary mixtures

Abstract

Simple and very sensitive spectrofluorimetric methods were developed for determination of adrenaline (I) procaine hydrochloride (II) mixture and salbutamol sulfate (III) guaifenesin (IV) mixture. Adrenaline (I) in the first mixture was determined by coupling with 5-diazo-1,2,4-triazolo-3-carboxylic acid (DTCA) reagent in alkaline medium forming fluorigenic product which can be measured at 340 nm (λex. 245 nm), while procaine hydrochloride (II) gave no fluorescence. Salbutamol sulfate (III) was analyzed by reaction with ethyl acetoacetate (EAA) forming coumarin derivative, which can be measured at 320 nm (λex. 280 nm). Guaifenesin (IV), the second drug in mixture has a considerable native fluorescence in methanol was measured at 310 nm (λex. 230 nm). All variables affecting reaction conditions were optimized. Linear correlations were obtained over the range of 19-100, 37-400 and 22-150 ng/ml for (I), (III) and (IV), respectively. The proposed methods were successfully applied for the analysis of the studied drugs in their pure and commercial dosage forms and the obtained results were in good agreement with those obtained from the reported methods; no significant difference in the accuracy and precision as revealed by the accepted values of t- and F-tests, respectively.