Acta Chimica Sinica ›› 2004, Vol. 62 ›› Issue (20): 2081-2088. Previous Articles     Next Articles

功能化纳米金增强的DNA电化学检测和序列分析

李金花, 胡劲波   

  1. 北京师范大学化学系, 北京, 100875
  • 投稿日期:2003-08-23 修回日期:2004-05-24 发布日期:2014-02-17
  • 通讯作者: 胡劲波,E-mail:hujingbo@bnu.edu.cn E-mail:hujingbo@bnu.edu.cn
  • 基金资助:
    国家自然科学基金会(No.20275007)资助项目.

Functional Gold Nanoparticle-enhanced Electrochemical Determination of DNA Hybridization and Sequence-specific Analysis

LI Jin-Hua, HU Jing-Bo   

  1. Department of Chemistry, Beijing Normal University, Beijing 100875
  • Received:2003-08-23 Revised:2004-05-24 Published:2014-02-17

An electrochemical determination method for the analyzing sequence-specific DNA using ferrocene-capped gold nanoparticles/streptavidin conjugates has been developed in this work. Thiolated DNA probes were covalently immobilized on a gold electrode with hexanethiol (HT) forming mixed self-assembled monolayer and hybridized with target DNA, containing a complementary sequence. Duplex (Double-stranded) DNA was formed on the gold surface. Then functional gold nanoparticles were introduced via strong interaction effect between biotin and streptavidin. Binding events were monitored by electrochemical signal of ferrocene covering on the gold nanoparticles by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The signal differences permitted to distinguish the match of two perfectly complementary DNA strands from the near-perfect match where just one base pair was wrong. The sensitivity of this electrochemical DNA biosensor has been detected and an excellent linearity of 0.001~10 nmol/L for 17-mer target concentration with the oxidation peak current and the limit of detection of 0.75×10-12 mol/L were also achieved.

Key words: DNA, functional gold nanoparticles, ferrocene, hybridization, base mutant