个人信息Personal Information
教授
博士生导师
硕士生导师
主要任职:化学学院副院长
其他任职:辽宁省教学名师,宝钢优秀教师特等奖提名奖,中国分析测试学会青年学术委员会委员
性别:女
毕业院校:南京大学
学位:博士
所在单位:化学学院
学科:分析化学. 生物化学与分子生物学
办公地点:化工综合楼C305
电子邮箱:wushuo@dlut.edu.cn
Ultrasensitive enzyme-free electrochemical immunosensor based on hybridization chain reaction triggered double strand DNA@Au nanoparticle tag
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论文类型:期刊论文
发表时间:2014-03-01
发表刊物:TALANTA
收录刊物:SCIE、EI、PubMed
卷号:120
页面范围:218-223
ISSN号:0039-9140
关键字:Electrochemical immunosensor; Signal amplification; Hybridization chain reaction; Carcinoembryonic antigen; Hexaammineruthenium
摘要:An ultrasensitive enzyme-free electrochemical immunoassay was developed for detection of the fg/mL level carcinoembryonic antigen (CEA) by using a double strand DNA@Au nanoparticle (dsDNA@AuNP) tag and hexaammineruthenium(III) chloride (RuHex) as the electroactive indicator. The dsDNA@AuNP was synthesized by one-pot hybrid polymerization of dsDNA on initiator DNA modified AuNPs via hybridization chain reaction. The immunosensor was prepared by covalently cross-linking capture antibody on chitosan/AuNP nanocomposite modified glass carbon electrode. The AuNPs accelerated the electron transfer and led to high detection sensitivity. With a sandwich-type immunoreaction and a biotin-streptavidin affinity reaction, the dsDNA@AuNP tag was conjugated on the immunocomplex to bring a high amount of RuHex to the electrode surface via electrostatic interaction, resulting in an amplified electrochemical signal. Under optimal conditions, the proposed sensing platform showed a wide linear detection range from 10 fg/mL to 10 ng/mL along with a detection limit of 3.2 fg/mL for CEA. The immunosensor exhibited high sensitivity and good stability, showing a promising application in early cancer diagnosis and could be extended to sensitive electrochemical biosensing of other analytes. (C) 2013 Elsevier B.V. All rights reserved.