Utility of tetrazolium blue for the spectrophotometric determination of azlocillin and ceftriaxone

A simple and sensitive spectrophotometric method was described for the assay of azlocillin and ceftriaxone in injections. The method was based on the reduction of tetrazolium blue in alkaline medium by the two drugs, giving a highly colored formazan measurable at 524 nm. The optimization of the different experimental conditions was described. The method proved to be accurate and reproducible as indicated by a relative st and ard deviation of less than 2%