Determination of Diflunisal in Tablets Using Derivative UV Spectrophotometric Methods

In this study, derivative UV spectrophotometric methods were developed for the analysis of diflunisal, which is used as a nonsteroidal anti-inflammatory drug. Analysis wavelengths of diflunisal for the first and second order derivative UV spectrophotometric methods were obtained as 235.6 nm and 228.8 nm, respectively. The linearity ranges were found as 1.0-25.0 μg mL-1 for the first order and 1.0-20.0 μg mL-1 for the second order derivative UV spectrophotometric method. The detection limit was 0.1 μg mL-1 for both developed methods. Derivative UV spectrophotometric methods were also applied to the synthetic samples and tablets containing diflunisal. The results of tablet analysis, which were obtained by derivative UV spectrophotometric methods, were compared with spectrofluorimetric method in the literature. No statistically significant difference was found between diflunisal concentrations obtained from the three methods. The mean percentage recoveries and mean relative standard deviations were found to be 100.00% and 0.27% for the first order and 99.94% and 0.26% for the second order derivative UV spectrophotometry. The precision and accuracy of the methods were found to be lower than 2% by statistical evaluation.