Polarographic Methods for Determination of Ascorbic Acid in Pharmacetical Preparations

Abstract

 Abstract—Ascorbic acid is determined polarographically present in various types of medicinal samples by internal standard addition method. Potassium hydrogen phthalate buffer (pH 4.0) containing 0.25% oxalic acid and 0.008 % gelatin solution used as supporting electrolytes and maxima suppressor. Presence of colouring matters does not interfere, and sample handling and solution preparation for analysis can be carried out sufficiently fast to prevent appreciable oxidation. Polarographic determination of ascorbic acid can be carried out even in presence of comparable amounts of other ingredients such as Vitamins A, B, C, D, and E. Results of estimation of ascorbic acid present in different multivitamin medicinal samples by internal standard addition method obtained are in good agreement with the quoted values. The method is precise as indicated by low values of standard deviation. Comparative study of ascorbic acid estimation by polarographic internal standard addition method with respect to their manufacturing company was also done.