化学学报 ›› 2009, Vol. 67 ›› Issue (18): 2144-2148. 上一篇    下一篇

研究论文

基于纳米金探针和基因芯片的DNA检测新方法

包 华a,b 贾春平*,b 周忠良a 金庆辉b 赵建龙b   

  1. (a华东师范大学生命科学学院 上海 200062)
    (b中国科学院上海微系统与信息技术研究所 上海 200050)
  • 投稿日期:2008-11-26 修回日期:2009-03-19 发布日期:2009-12-31
  • 通讯作者: 贾春平

A Novel DNA Detection Method Based on Gold Nanoparticle Probes and Gene Chips

Bao, Hua a,b Jia, Chunping *,b Zhou, Zhongliang a Jin, Qinghui b Zhao, Jianlong b   

  1. (a School of Life Science, East China Normal University, Shanghai 200062)
    (b Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050)
  • Received:2008-11-26 Revised:2009-03-19 Published:2009-12-31
  • Contact: Jia, Chunping

运用荧光纳米金探针和基因芯片杂交建立一种新的DNA检测方法. 荧光纳米金探针表面标记有两种DNA探针: 一种为带有Cy5荧光分子的信号探针BP1, 起信号放大作用; 另一种为与靶DNA一部分互补的检测探针P532, 两种探针比例为5∶1. 当靶DNA存在时, 芯片上捕捉探针(与靶DNA的另一部分互补)通过碱基互补配对结合靶DNA, 将靶DNA固定于芯片上; 荧光纳米金探针通过检测探针与靶DNA及芯片结合, 在芯片上形成“三明治”复合结构, 最后通过检测信号探针上荧光分子的信号强度来确定靶DNA的量. 新方法检测灵敏度高, 可以检测浓度为1 pmol/L的靶DNA, 操作简单, 检测时间短. 通过改进纳米金探针的标记和优化杂交条件, 可进一步提高核酸检测的灵敏度, 这将在核酸检测方面具有重要的应用价值.

关键词: 纳米金探针, 荧光探针, 基因芯片, 杂交, DNA检测

A new DNA detection method based on fluorescent gold nanoparticle (AuNP) probes and DNA chips was introduced here. Firstly, chips were modified with amine-oligonucleotide probe complementary to target DNA (capture probe). Gold nanoparticles were modified with two types of probes, one was another thiolated-oligonucleotide probe complementary to target DNA (detecting probe) and the other was thiolated-oligonucleotide probe without homologous sequence to detected samples (signal probe). The end of signal probe opposite the gold nanoparticles was modified with Cy5. The ratio of them is 1∶5. Through hybridization, the sandwich structures (DNA chip-target DNA-AuNP probes) were formed. Excess samples and AuNP probes were removed by washing for several times. And the amount of target DNA was determined by detecting the fluorescent signal of the AuNP probes. Low to 1 pmol/L target DNA could be detected with this method. Because the signal DNA probe with fluorescence rather than the target DNA was identified in this approach, the different proportions of detecting probe and signal probe could affect the detection signal significantly. Effect of different proportions of probes on detecting signal would be studied at a ratio of 1∶30, 1∶60, 1∶100 and higher sensitivity would be achieved. So, this will be one of the most important DNA detection methods.

Key words: gold nanoparticle probe, fluorescent probe, DNA chip, hybridization, DNA detection