Photochemical properties and toxicity of fluoroquinolone antibiotics impacted by complexation with metal ions in different pH solutions  

作　　者：Shengkai Cao Peng Zhang Heming Song Linke Ge Junfeng Niu 

机构地区：[1]School of Environmental Science and Engineering,Shaanxi University of Science&Technology,Xi’an 710021,China [2]Lancaster Environment Centre,Lancaster University,Lancaster LA14YQ,United Kingdom [3]College of Environmental Science and Engineering,North China Electric Power University,Beijing 102206,China

出　　处：《Journal of Environmental Sciences》2025年第4期149-158,共10页环境科学学报(英文版)

基　　金：supported by the National Natural Science Foundation of China(Nos.21976045 and 22076112);China Scholarship Council(CSC)Scholarship(Nos.202208610125 and 202308610123);Shaanxi Key Laboratory of Environmental Monitoring and Forewarning of Trace Pollutants(No.SHJKFJJ202318);the Key Research and Development Program of Shaanxi Province(No.2024SF-YBXM-567).

摘　　要：Acid-base dissociable antibiotic-metal complexes are known to be emerging contaminants in the aquatic environments.However,little information is available on the photochemical properties and toxicity of these complex forms.This study investigated the spectral properties of three fluoroquinolones(FQs)with and without metal ions Fe(III),Cu(II),and Al(III)in solutions under different pH conditions,as well as evaluated the changes in toxicity due to the complex with thesemetal ions using luminescent bacteria(vibrio fischeri).FQs showed a higher tendency to coordinate metal ions under alkaline conditions compared to neutral and acidic conditions,and the formation of complexes weakened the ultravioletabsorbing ability of FQs.At pH=7.0,Cu(II)quenched the fluorescence intensity of FQs.Moreover,their Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy were explored,revealing that the coordination sites of Cu(II)in three FQs were situated in a bidentate manner through the oxygen atom of the deprotonated carboxyl group and cyclic carbonyl oxygen atom.This conclusion was further verified by the theory of molecular surface electrostatic potential.In addition,except for complexes of ciprofloxacin-metals,enhanced toxicity of FQs upon coordination with Fe(III)was observed,while reduced toxicity was found for coordination with Cu(II)and Al(III).These results are important for accurately evaluating the photochemical behavior and risk of these antibiotics in aquatic environments contaminated with metal ions.

关 键 词：FLUOROQUINOLONE Photochemical properties Metal coordination Spectral analysis TOXICITY 

分 类 号：O62[理学—有机化学]