title: Reaction of antibiotic sulfadiazine with manganese dioxide in aqueous phase: Kinetics, pathways and toxicity assessment.
abstract: Sulfonamide antibiotics are often detected in terrestrial and aquatic environment, but little is known about abiotic degradation of these antibiotics. In the present study, the degradation of the sulfonamide antibiotic sulfadiazine by a synthesized δ-MnO2was investigated. The initial reaction rate of sulfadiazine oxidized by manganese dioxide increased as the solution pH decreased by weakening electrostatic attraction between sulfadiazine and MnO2and enhancing the reduction potential of MnO2. The presence of metal ions (Mn2+, Na+and Ca2+), especially Mn2+, decreased the initial reaction rate by competitively adsorbing and reacting with MnO2. Two different products were identified during the reaction of sulfadiazine with MnO2and the transformation of parent compound started with the formation of sulfadiazine radicals. Furthermore, toxicity assay results showed that the toxicity of products produced by bacteria decreased with elapse of reaction time. Results from the present study indicate that manganese dioxides in environmental matrix could be helpful in dissipation of sulfadiazine released into the environment.
authors: a State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha , China.|b Chemistry and Chemical Engineering College, Hunan University of Arts and Science , Changde , China.|c State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou , China.
authors: Ji-Feng
authors: JF
authors: Yang
authors: a State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha , China.
authors: Li-Ming
authors: LM
authors: Yang
authors: c State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou , China.
authors: Guang-Guo
authors: GG
authors: Ying
authors: a State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha , China.
authors: Cheng-Bin
authors: CB
authors: Liu
authors: b Chemistry and Chemical Engineering College, Hunan University of Arts and Science , Changde , China.
authors: Li-Ying
authors: LY
authors: Zheng
authors: a State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University , Changsha , China.
authors: Sheng-Lian
authors: SL
authors: Luo
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000633:toxicity; D004926:Escherichia coli / Q000187:drug effects; D006801:Humans; D007700:Kinetics; D017895:Manganese Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D013411:Sulfadiazine / Q000737:chemistry* / Q000633:toxicity; D018675:Toxicity Tests; D014873:Water Pollutants / Q000737:chemistry* / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D017895:Manganese Compounds; D010087:Oxides; D014873:Water Pollutants; D014874:Water Pollutants, Chemical; D013411:Sulfadiazine; C016552:manganese dioxide
keywords: Kinetics; MnO2; oxidation; pathways; sulfadiazine; toxicity assessment