ABSTRACT
Two spectrophotometric methods were used to determine two substances simultaneously in a binary mix whichare diosmin (DSM) and hesperidin (HSP). First, we used the derivative spectrophotometry by the zero-crossingmeasurements based on the elaboration of the linear calibration graphs of first derivative values, which are plottedat 269 nm for HSP and 262.5 nm for DSM. Then, for the second method, we opted for the calculation of the peakabsorbance ratio λmax of both drug substances (DSM-HSP) in a binary mixture, and the percentage of drugs wasdetermined. Two different ratios were selected.The two methods presented are simple, selective, and reliable, providing satisfactory accuracy. The recoveriesobtained in both cases are good and agreed well with the reported values. The results confirmed that the methodscan be considered as a good alternative to other costly techniques, in particular, chromatographic techniques. Thesemethods can be used easily and effectively for simultaneous dosing of two active ingredients mixed in pharmaceuticalforms with precision. Furthermore, we can use them for monitoring the synthesis of DSM from HSP. Considering thetime saved by these methods presented in the brief period of the analysis, we can use them for daily quality assurance.