1ST AND 2ND DERIVATIVE SPECTROPHOTOMETRIC DETERMINATION OF CEFOPERAZONE AND SULBACTAM IN INJECTIONS

A simple, spectrophotometric assay to measure the concentrations of ce foperazone and sulbactam in injectable formulations is described. Sinc e zero-order spectra are subject to interference, derivative spectroph otometry was used to enhance the spectral details. A linear relationsh ip between derivative amplitudes and the concentrations of the compoun ds was found. Beer's law is obeyed up to 75 and 80 mug ml-1 of cefoper azone in the first and second derivative modes, respectively. and up t o 75 mug ml-1 of sulbactam in the second derivative mode. Detection li mits were 0.64 and 0.88 mug ml-1, respectively for cefoperazone in the first and second derivative modes and 0.30 mug ml-1 for sulbactam in the second derivative mode. The method is rapid, simple, does not requ ire a separation step and has successfully been applied to the assay o f commercial injections containing cefoperazone and sulbactam.