DEVELOPMENT AND VALIDATION OF A SPECTROFLUORIMETRIC METHOD FOR THE DETERMINATION OF PHENIBUT IN TABLET DRUGS

Abstract

The developed method for the quantitative determination of phenibut in tablet drugs is based on the dansylation reaction in an alkaline medium (pH 9.18). The reaction results in the formation of a fluorescent derivative with λem=505 nm and λex=335 nm. Optimal conditions were selected to complete the reaction: temperature and time of thermostatting (40 °C and 15 min), molar ratio of phenibut and dansyl chloride (1:1.4). The method was validated in parameters of specificity, linearity, precision and accuracy. A plot of fluorescence intensity versus concentration of phenibut over the range of 800-1200 ng/ml is described by the regression equation y =0.1003x+1.4685 ( r =0.9999). The limit of detection and limit of quantification were 29.55 и 89.54 ng/ml respectively.

Keywords

• fluorescence spectroscopy
• dansyl chloride
• phenibut
• tablet drug
• validation