Dynamic nano-Ag colloids cytotoxicity to and accumulation by Escherichia coli:Effects of Fe^3+,ionic strength and humic acid

作     者：Weicheng Zhang Bingyu Ning Caiyun Sun Ke Song Xin Xu Tao Fang Lunguang Yao Weicheng Zhang;Bingyu Ning;Caiyun Sun;Ke Song;Xin Xu;Tao Fang;Lunguang Yao

作者机构：Collaborative Innovation Center of Water Security for Water Source Region of Mid-line of South-to-North Diversion Project of Henan ProvinceNanyang Normal UniversityNanyang 473061China Henan Key Laboratory of Ecological Security for Water Source Region of Mid-line of South-to-North Diversion ProjectNanyang Normal UniversityNanyang 473061China State Key Laboratory of Motor Vehicle Biofuel TechnologyNanyang 473000China Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of SciencesBeijing 100049China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2020年第32卷第3期

页      面：180-193页

核心收录：

学科分类：07[理学] 09[农学] 0903[农学-农业资源与环境] 0713[理学-生态学] 

基　　金：supported by the Joint Funds of the National Natural Science Foundation of China (No.U1804109) the State Key Laboratory of Motor Vehicle Biofuel Technology (No.KFKT2018006) the Scientific Research and Service Platform Fund of Henan Province (No.2016151) the Key Scientific and Technological Research Projects in Henan Province (No. 192102310305) the Foundation of Henan Educational Committee (No.19A330003) the Foundation of Nanyang Normal University (No.2018ZX023) 

主　　题：Cytotoxicity mechanism Accumulation Nano-Ag colloids Escherichia coli Environmental factors 

摘      要：Released Ag ions or/and Ag particles are believed to contribute to the cytotoxicity of Ag nanomaterials,and thus,the cytotoxicity and mechanism of Ag nanomaterials should be dynamic in water due to unfixed Ag particle:Ag+ *** recent research found that the cytotoxicity of PVP-Ag nanoparticles is attributable to Ag particles alone in 3 hr bioassays,and shifts to both Ag particles and released Ag^+ in 48 hr ***,as a continued study,the cytotoxicity and accumulation of 50 and 100 nm Ag colloids in Escherichia coli were determined *** cytotoxicity and mechanisms of nanoAg colloids are dynamic throughout exposure and are derived from both Ag ions and *** accumulation by *** is derived mainly from extracellular Ag particles during the initial 12 hr of exposure,and thereafter mainly from intracellular Ag ***^3+ accelerates the oxidative dissolution of nano-Ag colloids,which results In decreasing amounts of Ag particles and particle-related ***^+ stabilizes nano-Ag colloids,thereby decreasing the bioavailability of Ag particles and particle-related *** acid(HA) binds Ag^+ to form Ag^+-HA,decreasing ion-related toxicity and binding to the *** surface,decreasing particle-related *** in complex conditions showed a stronger relative contribution to toxicity and accumulation than Na^+ or Fe^3+.The results highlighted the cytotoxicity and mechanism of nano-Ag colloids are dynamic and affected by environmental factors,and therefore exposure duration and water chemistry should be seriously considered in environmental and health risk assessments.