Colorimetric Determination of Cefadroxil and Ceftriazone in Pharmaceutical Dosage Forms

Purpose: To develop a simple, rapid and selective method for the spectrophotometric determination of cefadroxil and ceftriaxone using 1, 2- napthaquinone-4- sulfonic acid sodium.Methods: The method was based on the derivatization of cefadroxil and ceftriaxone with 1, 2-naphthaquinone-4- sulfonic acid sodium in alkaline medium to yield orange-colored products.Results: The reaction products of cefadroxil and ceftriaxone at their respective max of 475 and 480 nm showed linearity in the concentration range of 10 - 100 and 25 - 175 ìg/ml, respectively. Relative standard deviations of 0.82 % for cefadroxil and 0.95 % for ceftriaxone were obtained. Recoveries of cefadroxil tablets and ceftriaxone injection were in the range of 100.66 ± 0.98 and 99.38 ± 0.84 %, respectively.Conclusion: Recovery studies gave satisfactory results indicating that none of the major additives/excipients interfered with the assay method. Therefore, the proposed method is simple, rapid, precise and convenient for the assay of cefadroxil and ceftriaxone in commercial preparations