[High-performance liquid chromatographic micro-assay for cefradine in biological fluids (author's transl)]

Recently, cephalosporins have been developed progressively that the clinical experiences in new cephalosporins have been reported one after another; some of them are widely used in daily medicine. The microbiological studies and other metabolic studies; i.e. absorption, distribution, and excretion, have undertaken simultaneously during the clinical trials of new antibiotics. On the other hand, the necessity of the optimum dose regimen for not only antibiotics but also other drugs has been emphasized to achieve the maximum pharmacological effects with minimal dosage or to prevent the side-effects and sequelae. In such cases, the monitoring of the blood level is essential and the drug concentration is necessary to be measured as soon as possible. The chemical assay has an advantage in this point over the bioassay, and has become available for the routine analysis recently. With cephalosporins, the blood and urine levels of cephalothin (CET), cefoxitin (CFX), cephalexin (CEX)(2,3), cefazolin (CEZ)(4), cefuroxime (CXM)(5), cephaloridine (CER)(6) and cefradine (CED)(7) determined by high-performance liquid chromatography (HPLC) have been reported. The author describes a new HPLC method using a reversed phase column which found to be applicable to the routine analysis of CED in serum and urine comparing with bioassay.