G-Quadruplex DNAzyme-Based Chemiluminescence Biosensing Strategy for Ultrasensitive DNA Detection: Combination of Exonuclease III-Assisted Signal Amplification and Carbon Nanotubes-Assisted Background Reducing
G-Quadruplex DNAzyme-Based Chemiluminescence Biosensing Strategy for Ultrasensitive DNA Detection: Combination of Exonuclease III-Assisted Signal Amplification and Carbon Nanotubes-Assisted Background Reducing
复制标题
基于 G-四链 DNAzyme 的超灵敏 DNA 检测化学发光生物传感策略：核酸外切酶 III 辅助信号放大和碳纳米管辅助背景降低的组合
DOI：
10.1021/ac402728d
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发表时间：
2013-12-03
影响因子：
7.4
通讯作者：
Li, Baoxin
中科院分区：
文献类型：
--
作者：
Gao, Yuan;Li, Baoxin
超低浓度特定核酸序列的检测对于基因相关疾病的早期诊断和生物防御应用具有重要意义。在此，我们报道了一种用于超灵敏 DNA 检测的放大化学发光 (CL) 生物传感平台。它基于核酸外切酶III辅助靶标循环扩增和G-四链体血红素DNAzyme的催化作用，在H2O2和鲁米诺存在下刺激CL的生成。此外，通过将多余的氯化血红素吸附在单壁碳纳米管表面，然后通过离心去除，可以有效解决过量氯化血红素本身引起的高背景问题。因此，我们提出的生物传感对目标 DNA 表现出高灵敏度，检测限为 12 fM，比基于 DNAzyme 的 CL 传感器（无需 Exo III 辅助扩增进行 DNA 检测）低约 100 倍。该传感平台为 DNA 的灵敏检测提供了一种无标记且经济高效的方法。
Detection of ultralow concentration of specific nucleic acid sequences is important in early diagnosis of gene-related diseases and biodefense application. Herein, we report an amplified chemiluminescence (CL) biosensing platform for ultrasensitive DNA detection. It is based on the exonuclease III-assisted target recycling amplification and catalytic effect of G-quadruplex hemin DNAzyme to stimulate the generation of CL in the presence of H2O2 and luminol. Moreover, the typical problem of high background induced by excess hemin itself can be effectively addressed through the absorbing of superfluous hemin on the surface of single-walled carbon nanotubes and then removing though centrifugation. Therefore, our proposed biosensing exhibited a high sensitivity toward target DNA with a detection limit of 12 fM, which was about 100-fold lower than that of the DNAzyme-based CL sensor for DNA detection without Exo III-assisted amplification. This sensing platform provides a label-free and cost-effective approach for sensitive detection of DNA.