The extra-weak chemiluminescence generated during oxidation of some tetracycline antibiotics. 1. Autoxidation.

Chemiluminescence (CL) appearing during autoxidation of tetracycline (TC) antibiotics has been studied. The CL spectrum consists of four emission bands with maxima at 520, 585, 640 and 700 nm. The bands at 585, 640 and 700 nm are similar to those observed for singlet molecular oxygen (1O2). The effect of 1O2 quenchers and free radical reaction inhibitors on the light emission is also reported. The data support the concept that, during the autoxidation of TCs, cytotoxic oxygen species such as HO., O2.-, H2O2 and 1O2 are formed.