Determination of thiamine, riboflavin and pyridoxine in pharmaceuticals by synchronous fluorescence spectrometry in organized media

Synchronous fluorescence possibilities for the determination of three water-soluble vitamins, thiamine, pyridoxine and riboflavin, in presence of bis-2-ethylhexysulfosuccinate sodium salt (AOT) micelles, were studied. Synchronous fluorescence was chosen due to the good analytical characteristics found. Repeatability, expressed as %R.S.D. was smaller than 1.4, sensitivity calculated as the slope of the straight line was of the order of 1010lmol-1cm-1 in all the cases and detection limits were 12µgl-1 for thiamine, 10µgl-1 for pyridoxine and 9µgl-1 for riboflavin. Synchronous fluorescence was applied to carry out the analysis of the three vitamins in pharmaceuticals.