Abstract
A rapid and accurate high performance liquid chromatographic (HPLC) method for the determination of cephalexin in the human serum and urine has been developed. As internal standard, cephaloglycin and o-acetoanisidide are added to the serum and urine specimens, respectively. The serum specimens are deproteinized with trichloroacetic acid and the excess of trichloroacetic acid is removed by extraction with ether. After these pretreatments, cephalexin in the biological fluid is separated with Unisil 10 C 18 column and detected by UV-detector. It is confirmed that the serum and urine concentrations of cephalexin determined by this method agree well with those by bioassay. This method may be used more available for a clinical pharmacokinetic study and a bioavailability study of cephalexin.