Croatica Chemica Acta, Vol. 88 No. 1, 2015.
Original scientific paper
https://doi.org/10.5562/cca2551
Spectrophotometric Determination of L-Ascorbic Acid in Pharmaceuticals Based on Its Oxidation by Potassium Peroxymonosulfate and Hydrogen Peroxide
Mirsad Salkić
orcid.org/0000-0002-2540-3784
; Department of Analytical Chemistry, Faculty of Technology, University of Tuzla, 75000 Tuzla, Bosnia and Herzegovina
Amra Selimović
; Department of Analytical Chemistry, Faculty of Technology, University of Tuzla, 75000 Tuzla, Bosnia and Herzegovina
Abstract
Two new, accurate, precise, and sensitive spectrophotometric methods were developed for
the assay of L-ascorbic acid in pharmaceutical preparations. The determination of L-ascorbic acid was
based on its oxidation by potassium peroxymonosulfate (method A) and hydrogen peroxide in the
presence of Cu(II) as a catalyst (method B). The molar absorptivities were found to be 1.48×104 and
1.06×104 L mol–1 cm–1 for methods A and B, respectively. Beer's law was obeyed in the concentration
range of 0.65–11.20 μg mL–1 for method A and 0.51–16.00 μg mL–1 for method B. Other compounds
commonly found in vitamin C and multivitamin products did not interfere with the determination of
L-ascorbic acid.. The proposed methods were successfully applied for the determination of L-ascorbic acid
in pharmaceutical formulations. The results obtained with the proposed methods showed good agreement
with those given by the titrimetric method using iodine.
Keywords
L-Ascorbic acid; peroxymonosulfate; hydrogen peroxide; spectrophotometry; pharmaceutical preparations
Hrčak ID:
139132
URI
Publication date:
27.3.2015.
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