Jornal de Química Analítica Ambiental

Photo-Degradation of Amoxicillin, Streptomycin, Erythromycin and Ciprofloxacin by UV and UV/TiO2 Processes. Evaluation of Toxicity Changes Using a Respirometric Biosensor

Abstract

Raffaella Palmisano, Luigi Campanella and Barbara Ambrosetti

Current research aims to conserve natural resources, especially water. Our study focuses on developing water purification to remove contaminating antibiotics using heterogeneous photo-catalysis. We compare photolysis with and without TiO2 catalysis, testing the photo-stability of four representative antibiotics: Amoxicillin, streptomycin, erythromycin and ciprofloxacin by HPLC using a Perkin Elmer 2000 chromatograph, BIO-RAD Bio-sil ODS-5S L 250 mm × 4 mm ID C18 reversed phase column and Perkin Elmer LC-90 UV detector. Both obeyed first order reaction kinetics, usually following the Lagmuir-Hinshelwood model. A respirometric biosensor was employed to assess the toxicity of drug solutions and photo-degradation products. We demonstrate that catalysis consistently decreases toxicity more effectively in all cases. The photo-degradation of ciprofloxacin and amoxicillin took longer.