Photocatalytic degradation of ofloxacin and evaluation of the residual antimicrobial activity

Author(s)

Peres, M. S. ^[1] ; Maniero, M. G. ^[1] ; Guimaraes, J. R. ^[1]

Affiliation

^[1] Univ Estadual Campinas, FEC DSA, Campinas, SP - Brazil

• Document type: Journal article
• Source: PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES; v. 14, n. 3, p. 556-562, MAR 1 2015.
• Web of Science Citations: 26

Abstract

Ofloxacin is an antimicrobial agent frequently found in significant concentrations in wastewater and surface water. Its continuous introduction into the environment is a potential risk to non-target organisms or to human health. In this study, ofloxacin degradation by UV/TiO2 and UV/TiO2/H2O2, antimicrobial activity (E. coli) of samples subjected to these processes, and by-products formed were evaluated. For UV/TiO2, the degradation efficiency was 89.3% in 60 min of reaction when 128 mg L-1 TiO2 were used. The addition of 1.68 mmol L-1 hydrogen peroxide increased degradation to 97.8%. For UV/TiO2, increasing the catalyst concentration from 4 to 128 mg L-1 led to an increase in degradation efficiency. For both processes, the antimicrobial activity was considerably reduced throughout the reaction time. The structures of two by-products are presented: m/z 291 (9-fluoro-3-methyl-10-(methyleneamino)-7-oxo-2,3-dihydro-7H-{[}1,4]oxazi no{[}2,3,4-ij]quinoline-6-carboxylic acid) and m/z 157 ((Z)-2-formyl-3-((2-oxoethyl)imino)propanoicacid). (AU)

• FAPESP's process: 13/07817-2 - Degradation of sulfonamides and tetraciclines by UV/H2O2 and O3: evaluation of antimicrobial activity and toxicity
• Grantee: Milena Guedes Maniero Ferreira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/09543-7 - Residues of veterinary drugs in the environment
• Grantee: Susanne Rath
• Support Opportunities: Research Projects - Thematic Grants