High-pressure liquid chromatographic assay of sulbactam in plasma, urine, and tissue.

A reverse-phase high-pressure liquid chromatography method for the quantitation of sulbactam in plasma, urine, and tissue is described. The assay used the formation of an imidazole derivative followed by extraction with acetonitrile and dichloromethane and used UV absorbance for detection. The mobile phase consisted of acetonitrile, tetrabutylammonium hydroxide, and phosphate buffer. The assay was linear from 100 micrograms/ml (g of tissue) to 1 microgram/ml (g). Within- and between-batch recovery was greater than 90%. The coefficient of variation was generally less than 15%. There were no interfering peaks in the quantitation of sulbactam.