Capture-SELEX for Chloramphenicol Binding Aptamers for Labeled and Label-Free Fluorescence Sensing  

作　　者：Yichen Zhao Albert Zehan Li Juewen Liu 

机构地区：[1]Department of Chemistry,Waterloo Institute for Nanotechnology,Water Institute,University of Waterloo,Waterloo,Ontario N2L 3G1,Canada

出　　处：《Environment & Health》2023年第2期102-109,共8页环境与健康（英文）

基　　金：Funding for this work was from the Natural Sciences and Engineering Research Council of Canada(NSERC)and a Strathclyde/Waterloo Joint Transatlantic Funding。

摘　　要：Chloramphenicol(CAP)is a potent antibiotic.Due to its side effects,CAP is currently banned in most countries,but it is still found in many food products and in the environment.Developing aptamer-based biosensors for the detection of CAP has interested many researchers.While both RNA and DNA aptamers were previously reported for CAP,they were all obtained by immobilization of the CAP base,which omitted the two chlorine atoms.In this work,DNA aptamers were selected using the libraryimmobilized method and free unmodified CAP.Three families of aptamers were obtained,and the best one named CAP1 showed a dissociation constant(K_(d))of 9.8μM using isothermal titration calorimetry(ITC).A fluorescent strand-displacement sensor showed a limit of detection(LOD)of 14μM CAP.Thioflavin T(ThT)staining allowed label-free detection of CAP with a LOD of 1μM in buffer,1.8μM in Lake Ontario water,and 3.6μM in a wastewater sample.Comparisons were made with previously reported aptamers,and ITC failed to show binding of a previously reported 80-mer aptamer.Due to the small size and well-defined secondary structures of CAP1,this aptamer will find analytical applications for environmental and food monitoring.

关 键 词：aptamers biosensors SELEX CHLORAMPHENICOL ANTIBIOTICS fluorescence 

分 类 号：TP212.3[自动化与计算机技术—检测技术与自动化装置]