Flow Injection Chemiluminescence Determination of Cephalosporin Antibiotics by Their Enhancing Effects on Luminol-Potassium Periodate System

It was found that the chemiluminescence arising from the reaction of luminol with KIO₄ in alkaline solution could be strongly enhanced by cephalosporin antibiotics. Based on these observations, a new flow injection chemiluminescence method is proposed for the determination of four cephalosporin antibiotics: cefalexin, cefaclor, cefradine, and cefadroxil. The detection limits of the method are 0.9 ng mL^-1 cefalexin, 0.4 ng mL^-1 cefaclor, 10 ng mL^-1 cefradine, and 10 ng mL ^-1 cefadroxil. The method was successfully applied to the determination of four cephalosprin antibiotics in pharmaceutical preparations.