TLC-densitometric and first derivative spectrophotometric methods for determination of cefoxitin-sodium in presence of its alkali-induced degradation product

Abstract

Two simple and accurate methods were developed for quantitative estimation of cefoxitin sodium in presence of its open ring alkali-induced degradation product. The first method was based on TLC separation of the drug from its alkali-induced degradation product followed by densitometric measurement of the intact drug at 254 nm. The proposed method obeys Beer’s law in range (1–20 µg/band). The second method was first derivative (1D) spectrophotometric method; was based on measurement of amplitude of first order spectra of cefoxitin sodium (in the range of 4–36 µg mL−1) at 282 nm which showed zero crossing point of its degradation product. The two methods were validated according to ICH guideline for accuracy, precision and were successfully applied for the determination of the drug in pure form and pharmaceutical preparation in presence of its alkali-induced degradation product. Keywords: Cefoxitin sodium, Stability indicating methods, Thin layer chromatography (TLC)-densitometry, First derivative (1D) spectrophotometric method