Fe^(3+)选择性吸附碳量子点抑制细菌生长和细菌生物膜生成  

Fe^(3+)Selective Adsorption of Carbon Dots to Inhibit Bacterial Growth and Biofilm Formation

作　　者：郎丰亭 钟睦琪 孙泽鑫 李康 郝智慧[2] LANG Feng-ting;ZHONG Mu-qi;SUN Ze-xin;LI Kang;HAO Zhi-hui(College of Chemistry and Pharmacy,Qingdao Agricultural University,Qingdao 266109,China;College of Veterinary Medicine,China Agricultural University,Beijing 100193,China)

机构地区：[1]青岛农业大学化学与药学院,山东青岛266109 [2]中国农业大学动物医学院,北京海淀100193

出　　处：《中国兽医杂志》2023年第5期31-35,共5页Chinese Journal of Veterinary Medicine

基　　金：山东省重点研发计划(2019GSF107073)。

摘　　要：为了有效抑制细菌感染,寻找新的抗生素增效作用剂协助抗生素治疗,本试验通过一步水热法,以柠檬酸和聚赖氨酸制备了碳量子点(CDs),使用紫外-可见分光光度计和成像仪对CDs进行表征,采用微量肉汤稀释法、棋盘法和结晶紫染色法检测CDs对细菌生长和细菌生物膜生成的影响,通过细胞毒性和溶血活性试验评估CDs的体外生物相容性。结果显示,CDs在345 nm处可观察到明亮蓝色荧光,可选择性吸附作为生物膜必要元素之一的Fe^(3+),对Fe^(3+)的响应浓度为1 mmol/L,且CDs在日光条件下的10 h内保持荧光稳定;CDs对耐甲氧西林金黄色葡萄球菌(MRSA)、革兰阳性菌(金黄色葡萄球菌,S.aureus)和革兰阴性菌(大肠埃希菌,E.coli)的最小抑菌浓度(MIC)分别是256、128和256μg/mL;CDs联合头孢噻肟可有效抑制革兰阴性菌生长[分级抑菌浓度(FIC)=0.07];CDs(62.5μg/mL)对MRSA和E.coli的生物膜抑制率分别为64.4%和57.4%;且CDs(1000μg/mL)没有细胞毒性(细胞活性>100%)和溶血活性(<1%)。结果表明,CDs具有作为抗生素增效剂的潜力,可与抗生素联合使用治疗革兰阴性菌引起的感染。For effective inhibition of bacteria and search for new antibiotic potentiating agents to enhance antibiotics in the treatment of infections,in this study,carbon dots(CDs)were prepared by one-step hydrothermal method with citric acid and polylysine,and characterized using UV-Vis spectrophotometer and imager;their inhibition on bacterial growth and biofilm formation were assessed by micro-broth dilution method,checkerboard method and crystalline violet staining;and their cytotoxicity and hemolytic activity were evaluated in vitro.The results showed that CDs fluoresced bright blue at 345 nm,selectively adsorbed Fe^(3+),one of the essential elements for biofilms,and responded to Fe^(3+)at a concentration of 1 mmol/L;CDs remained fluorescently stable within 10 h under daylight conditions;the minimum inhibitory concentration(MIC)of CDs against methicillin-resistant Staphylococcus aureus(MRSA),Gram-positive bacteria(Staphylococcus aureus,S.aureus)and Gram-negative bacteria(Escherichia coli,E.coli)were 2560x0E䥺SymbolmA@0x0Fg/mL,1280x0E䥺SymbolmA@0x0Fg/mL,and 2560x0E䥺SymbolmA@0x0Fg/mL,respectively;CDs combined with cefotaxime effectively inhibited the growth of Gram-negative bacteria[fractional inhibitory concentration(FIC)=0.07];the biofilm inhibition rates of CDs(62.50x0E䥺SymbolmA@0x0Fg/mL)for MRSA and E.coli were 64.4%and 57.4%,respectively;CDs(10000x0E䥺SymbolmA@0x0Fg/mL)had no cytotoxicity(cell viability>100%)and hemolytic activity(<1%).Thus,CDs have the potential to act as a synergistic agent of antibiotics,and can be used in combination with antibiotics to treat infections with Gram-negative bacteria.

关 键 词：碳量子点 Fe^(3+)吸附 生物膜 增效作用 生物相容性 

分 类 号：S859.5[农业科学—临床兽医学]