Validated capillary electrophoresis method for the simultaneous determination of formic acid and acetic acid in Cephalosporin drug substances using indirect UV detection

摘要

A rapid and sensitive capillary electrophoresis (CE) method was developed for the determination of formic acid and acetic acid content in Cephalosporin drugs using a background electrolyte (solution containing 5 mM Potassium hydrogen phthalate and 0.25 mM cetyltrimethyl ammonium bromide as a flow modifier adjusted to pH 7.2) along with an applied electric field of 20kV for 0.4 min. A 40cm fused silica capillary was used as a stationary phase. Indirect UV detection mode was employed for the determination of analyte at a wavelength of 210nm. Linearity and accuracy were performed in the concentration range of 5-50 μg mL-1 and 0.1-0.75 % w/w respectively for formic acid and 2-40 μg mL-1 and 0.04-0.75 %w/w respectively for acetic acid. The method was validated with respect to specificity, linearity, accuracy, precision, ruggedness, robustness, and stability in analytical solution. The limit of quantification and detection for formic acid was 2.516 μg mL-1 and 0.775 μg/mL respectively while for acetic acid was 1.820 μg mL-1 and 0.546 μg mL-1 respectively.