高等学校化学学报 ›› 2005, Vol. 26 ›› Issue (8): 1432.

• 研究论文 • 上一篇    下一篇

功能化纳米金放大的DNA电化学传感器研究

李金花, 胡劲波, 丁小勤, 李启隆   

  1. 北京师范大学化学系, 北京100875
  • 收稿日期:2004-06-15 出版日期:2005-08-10 发布日期:2005-08-10
  • 通讯作者: 胡劲波(1965年出生),女,副教授,主要从事生物电分析研究.E-mail:hujingbo@bnu.edu.cn E-mail:hujingbo@bnu.edu.cn
  • 基金资助:

    国家自然科学基金(批准号:20275007)资助.

DNA Electrochemical Biosensor Based on Functional Gold Nanoparticles-amplification

LI Jin-Hua, HU Jing-Bo, DING Xiao-Qin, LI Qi-Long   

  1. Department of Chemistry, Beijing Normal University, Beijing 100875, China
  • Received:2004-06-15 Online:2005-08-10 Published:2005-08-10

摘要: 研究了DNA夹心杂交和直接杂交体系,将功能化纳米金引入到标记有生物素的杂交双链上,制成具有电化学活性和纳米金放大作用的DNA电化学传感器,采用循环伏安法测试.在夹心杂交体系中,靶点DNA浓度与阳极峰电流关系曲线的相对标准偏差为3.0%~13.0%,在浓度为6.9×10-3~0.14nmol/L范围内得到良好的线性关系,检测限达到2.0×10-3nmol/L,实现了对单碱基突变的高灵敏检测和序列识别.直接杂交检测限为2.5×10-4mol/L,分别在2.5×10-4~5.0×10-3nmol/L和5.0×10-3~10nmol/L范围内得到峰电量与浓度的良好线性关系.并比较这两种体系.

关键词: DNA, 功能化纳米金, 二茂铁, 循环伏安

Abstract: Ferrocene(Fc)-capped gold nanoparticle/streptavidin conjugates were attached onto the electrodes covered with either biotinylated or sandwich oligodeoxynucleotides(ODNs) duplexes. The binding events were monitored by electrochemical signal of ferrocene. 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 mutant. The effects of the DNA probe and target strand lengths on the voltammetric behavior of the Fc groups were studied. It was found that shorter duplexes would lead to a more reversible voltammetric wave and a higher detection level. For the analysis of 30-mer biotinylated target DNA, a concentration level as low as 2.5×10-4 nmol/L could be detected while for 39-mer target of sandwich duplexes, the limit of detection was 2.0×10-3 nmol/L. The capabilities of the method for trace analysis of DNA can be attributed to the enhanced voltammetric detection by the large number of Fc moieties present in each conjugate.

Key words: DNA, Functional gold nanoparticles, Ferrocene, Cyclic voltammetry

中图分类号: 

TrendMD: