Ultrasensitive detection of micro RNA-21 in human serum based on the confinement effect enhanced chemical etching of gold nanorods  

作　　者：Min Huang Ru Cheng Shuai Wen Liangtong Li Jie Gao Xiaohui Zhao Chunmei Li Hongyan Zou Jian Wang 

机构地区：[1]Key Laboratory of Luminescence Analysis and Molecular Sensing(Southwest University),Ministry of Education,College of Pharmaceutical Sciences,Southwest University,Chongqing 400715,China [2]Department of Biological and Chemical Engineering,Chongqing University of Education,Chongqing 400067,China [3]The Ninth People’s Hospital of Chongqing,Chongqing 400700,China

出　　处：《Chinese Chemical Letters》2024年第9期382-386,共5页中国化学快报（英文版）

基　　金：financial supported from the National Natural Science Foundation of China(No.22174115);the Graduate Education and Teaching Reform Research Project of Chongqing(No.yjg223038);the Fundamental Research Funds for the Central Universities(No.SWU-XDJH202321)。

摘　　要：Natural enzymes,such as horseradish peroxidase(HRP),are a class of important biocatalysts with the high specificity,but their catalytic efficiency is usually unsatisfactory.Thus,the higher catalytic efficiency induced by the confinement effect is promising in optical sensing systems.In this work,a dark-field light scattering sensing platform was fabricated by the confinement effect of HRP from hybridization chain reaction(HCR)and then released to solution by the toehold-mediated strand displacement reaction(TSDR).Then,HRP catalyzed the 3,3,5,5-tetramethylbenzidine(TMB)to TMB^(2+)with the assistance of hydrogen peroxide,which etched the gold nanorods(Au NRs)with the weakened light scattering.The single-particle assay was established based on the decreased light scattering intensity of AuNRs under dark-field microscope.The proposed assay revealed excellent analytical performance within a linear range from 25 pmol/L to 600 pmol/L,and a low limit of detection of 3.12 pmol/L.Additionally,it also manifested satisfactory recovery of mi RNA-21 in human serum samples.The high sensitivity,excellent specificity,and universal applicability make this sensing platform promising for disease diagnosis.

关 键 词：Confinement effect Hybridization chain reaction Toehold-mediated strand displacement REACTION MICRORNA-21 Gold nanorods Dark-field microscope 

分 类 号：R446.1[医药卫生—诊断学] TB383.1[医药卫生—临床医学] O657[一般工业技术—材料科学与工程]