Rapid determination of sulbactam and tazobactam in human serum by high-performance liquid chromatography

A simple and rapid HPLC method for the determination of tazobactam and sulbactam, two beta-lactamase inhibitors, in serum for the therapeutic follow-up of patients is described. The effect of the pH of the aqueous mobile phase and column temperature on column efficiency and retention were examined and equations for their dependences were derived. The use of a chromatographic response function showed that methanol-buffer (5:95, v/v) (pH 6.3) as the mobile phase and a 45 degrees C column temperature were optimum values for chromatographic separation. The analytical method was linear from 10 to 200 micrograms/ml. This assay limit range is sufficient for the analysis of human serum. The limit of detection was 10 micrograms/ml for sulbactam and 5 micrograms/ml for tazobactam. The coefficient of variation was less than 5%. The speed at which this assay can be performed makes it especially useful for estimating the levels of these drugs in human serum.