Determination of Thiamine hydrochloride in its pure form and in its pharmaceutical formulation by oxidative coupling method

Abstract

Developed a new and accurate spectrophotometric method for the determination of thiamine hydrochloride (VitB1) in its pure form and in its pharmaceutical formulation. The method is based on adding increasing concentrations ranging from 20-100 µg/mL of VitB1 solution to a series of volumetric flask with a capacity of 10 ml, then adding 2 ml of the oxidizing agent potassium ferricyanide K₃Fe (CN) ₆ at a concentration of 1000 µg/mL The solution was heated to the boiling point, and then 2 ml of 4-Aminoantipyrene (4-AAP) reagent was added at a concentration of 1000 µg / ml and the volume was perfected to the brand distilled, and the absorbance was measured for the length of each solution against the Planck solution at 634 nm. The optimal conditions for product formation (type and volume of reagent, temperature, effect of pH, sequence of additives) were studied. The linearity of the method for the compound ranged from (20-100) µg/mL, The molar absorption coefficient was 1011.9 L / mol.cm, the Sandell significance was 0.33 µg / cm², the detection limit was 0.099 µg/mL, and the quantitative limit was 2.93066 µg/mL. The recovery percentage ranged between (97.944 - 100.50) % The relative deviation rate RSD% in the range of 0.639 - 4.894% for five readings (n = 5) and for all concentrations of the calibration curve in one day, while the values of the RSD% ranged in more than one day Between 0.965 - 4.958%. The method was successful for the determination of VitB1 in its pharmaceutical preparation by the direct method and the retrospective study method.