Liquid Chromatographic Assay of Cefuroxime in Serum

We describe a procedure for determining cefuroxime concentrations in serum by using high-performance liquid chromatography. The drug is extracted from serum with dimethylformamide and separated from other substances in the extract by reversed-phase chromatography. The ultraviolet (280-nm) absorption of the effluent was moni-tored and quantitated based on the height of the cefuroxime peak. Intra- and inter-assay imprecision (cv) was less than 3. 1 and 4.3 % , respectively. Serum concentrations as low as 1.0 mg/liter could be accurately measured. No inter-ference from various other drugs and antibiotics was found. A biological half-life of 52 mm in serum was observed after intravenous injection of the drug into a human volun-teer. High-performance liquid chromatography (HPLC), used to determine various antibiotics in biological fluids (1-7), has shown definite advantages over routine microbiological assays with regard to rapidity, precision, specificity, and sufficient sensitivity for clinical use. This report describes such a pro-cedure for determining cefuroxime (a new cephalosporin de-rivative with high stability to 9-lactamases) in serum. Briefly, the assay involves extraction of drug from samples with di-methylformamide, reversed-phase partition HPLC, and de-tection by on-line monitoring of the effluent absorption at 280 nm