Chemiluminescence of β-lactam antibiotics based on the luminol reaction Original Research Article

The chemiluminescence of luminol with β-lactam antibiotics was examined by flow injection analysis. It was found that chemiluminescence was directly produced by the reaction of β-lactam antibiotics with luminol in the presence of a catalyst in an alkaline solution without hydrogen peroxide. Hexacyanoferrate(III) and hexacyanoferrate(II) were used as catalyst for the reaction. To explain the mechanism of the chemiluminescence of luminol with β-lactam antibiotics, electron spin resonance (ESR) measurements were performed. ESR showed that hydroxy and superoxide radicals were generated from β-lactam antibiotics in the alkaline solution by using 5,5′-dimethyl-1-pyrroline N-oxide as a spin trap agent. Detection limits (S/N=3) of aztreonam, penicillin G, cephalothin, 6-aminopenicillanic acid, 7-aminocephalosporanic acid, panipenem, latamoxef and faropenem were 100, 60, 40, 20, 4, 2, 1 and 1 ng per injection, respectively.