Spectrophotometric Determination of Acidity Constants of Thiamine in Water, Water-Triton X-100 Micellar Media Solutions

In this work the acidity constants of Thiamine in water and water-Triton X-100 micelle media solutions, at 25 degrees C, have been determined spectrophotometrically. To evaluate the pH-absorbance data, a resolution based on the combination of soft-and hard-modeling is applied. The acidity constants of all related equilibria are estimated using the whole spectral fitting of the collected data to an established factor analysis model. DATAN program was applied for determination of acidity constants. Results showed that the pKa values of Thiamine were influenced as the percentages of a nonionic surfactant, such as triton X-100, added to the solution of this reagent increased. Effect of surfactant on acidity constants and pure spectrum of each component are also discussed.