Quantum Dot Nanobeads-Labelled Lateral Flow Immunoassay Strip for Rapid and Sensitive Detection of Salmonella Typhimurium Based on Strand Displacement Loop-Mediated Isothermal Amplification  

作　　者：Yuting Shang Shuzhen Cai Qinghua Ye Qingping Wu Yanna Shao Xiaoying Qu Xinran Xiang Baoqing Zhou Yu Ding Moutong Chen Liang Xue Honghui Zhu Jumei Zhang 

机构地区：[1]Guangdong Provincial Key Laboratory of Microbial Safety and Health&State Key Laboratory of Applied Microbiology Southern China&Institute of Microbiology,Guangdong Academy of Sciences,Guangzhou 510070,China [2]State Key Laboratory of Food Science and Technology&National Engineering Research Center for Functional Foods&Synergetic Innovation Center of Food Safety&Joint International Research Laboratory on Food Safety,School of Food Science and Technology,Jiangnan University,Wuxi 214122,China

出　　处：《Engineering》2022年第12期62-70,共9页工程（英文）

基　　金：This work was supported by the National Key Research and Development Program of China(2019YFC1606300);the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01S174);the Guangdong Academy of Sciences Special Project of Implementing Innovation-Driven Development Capacity Building(2018GDASCX-0401).

摘　　要：Rapid,sensitive,point-of-care detection of pathogenic bacteria is important for food safety.In this study,we developed a novel quantum dot nanobeads-labelled lateral flow immunoassay strip(QBs-labelled LFIAS)combined with strand displacement loop-mediated isothermal amplification(SD-LAMP)for quantitative Salmonella Typhimurium(ST)detection.Quantum dot nanobeads(QBs)served as fluorescence reporters,providing good detection efficiency.The customizable strand displacement(SD)probe was used in LAMP to improve the specificity of the method and prevent by-product capture.Detection was based on a sandwich immunoassay.A fluorescence strip reader measured the fluorescence intensity(FI)of the test(T)line and control(C)line.The linear detection range of the strip was 10^(2)–10^(8) colony forming units(CFU)·mL^(-1).The visual limit of detection was 10^(3) CFU·mL^(-1),indicating that the system was ten-fold more sensitive than AuNPs-labelled test strips.ST specificity was analyzed in accordance with agarose gel outputs of polymerase chain reaction(PCR)and SD-LAMP.We detected ST in foods with an acceptable recovery of 85%–110%.The method is rapid,simple,almost equipment-free,and suitable for bacterial detection in foods and for clinical diagnosis.

关 键 词：Salmonella Typhimurium Quantum dot nanobeads Lateral flow immunoassay strip Loop-mediated isothermal amplification Strand displacement probe 

分 类 号：TS207.4[轻工技术与工程—食品科学]