Photocatalytic degradation of outdated antibiotics by nano-crystalline ZnO

Photocatalytic oxidation of an outdated sample of Cefixime, a beta-lactam antibiotic, was carried in the presence of nanocrystalline ZnO catalyst prepared in-house and by using UV-light source. The degradation of cefixime was studied spectrophotometrically by measuring absorbance at λ_max of 287.5 nm. Comparison with the photodegradation of the sample in the presence of a bulk ZnO sample proved that the process of degradation was accomplished much faster (almost within half the duration) only in the presence of the in-house prepared nano-crystalline ZnO at ambient temperatures. Kinetic study revealed that the process follows a first order dependence on cefixime concentration. Nano-crystalline catalyst of ZnO has promising potential to effectively degrade antibiotic samples within short durations.