Utility of Tartrazine Dye in the Indirect Spectrophotometric Determination of Ceftriaxone and Cefotaxime

Abstract

The antibiotics ceftriaxone and cefotaxime, both in their pure forms and in pharmaceutical formulations, were determined spectrophotometrically using tartrazine dye. The method is based on the bromination of these drugs by a known excess of N-bromosuccinimide (NBS) in an acidic medium. The remaining NBS bleaches the lemon-yellow azo dye color of tartrazine, which was measured at 426 nm. The decolorization of the dye is proportional to the residual amount of NBS, which is, in turn, proportional to the concentration of the drugs. Lineovery percentages of 100.13 and 99.18%, molar absorptivity values of 1.07 × 10⁵ and 8.2 × 10⁴ L/(mol cm), and relative standard deviation of ≤1.789% for ceftriaxone and cefotaxime, respectively. The method is sensitive, simple, precise, accurate, and free from excipients. The developed method was successfully applied to determine these drugs in their pharmaceutical formulations, and the reaction mechanism was proposed.