• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biosensors & Bioelectronics: The International Journal for the Professional Involved with Research, Technology and Applications of Biosensers and Related Devices >Electrochemical DNA biosensor based on proximity-dependent DNA ligation assays with DNAzyme amplification of hairpin substrate signal
【24h】

Electrochemical DNA biosensor based on proximity-dependent DNA ligation assays with DNAzyme amplification of hairpin substrate signal

机译：电化学DNA生物传感器，基于接近依赖性DNA连接测定和发夹底物信号的DNAzyme扩增

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

This paper describes a novel electrochemical DNA sensor for the simple, sensitive and specific detection of nucleic acids based on proximity-dependent DNA ligation assays with the DNAzyme amplification of hairpin substrate signal. A long DNA strand contains the catalytic motif of Mg~(2+)-dependent 10-23 DNAzyme, acting as the recognition probe. When the target DNA was introduced into the system, part of it was complementary to 5'-end of the recognition probe, resulting in the ligation of a stable duplex, the unbinded part of the target DNA was acted as one binding arm for the DNAzyme. This duplex containing a complete 10-23 DNAzyme structure could cleave the purine-pyrimidine cleavage site of the hairpin substrate, which resulted in the fragmentation of the hairpin structure and the release of two single-stranded nucleic acids, one of which was biotinylated and acted as the signal probe. An immobilized thiolated capture probe could bind with the signal probe, using biotin as a tracer in the signal probe, and streptavidin-alkaline phosphatase (SA-ALP) as reporter molecule. The activity of the immobilized enzyme was voltammetrically determined by measuring the amount of 1-naphthol generated after 5min of enzymatic dephosphorylation of 1-naphthyl phosphate. The results revealed that the sensor showed a sensitive response to complementary target sequences of H. pylori in a concentration range from 100fM to 1nM, with a detection limit of 50fM. In addition, the sensing system could discriminate the complementary sequence from mismatched sequences, with high sensitivity and reusability.
机译：本文介绍了一种新型的电化学DNA传感器，该传感器可基于具有发夹结构底物信号的DNAzyme扩增的邻近依赖性DNA连接测定法，对核酸进行简单，灵敏和特异的检测。一条长DNA链包含Mg〜（2+）依赖性的10-23 DNAzyme的催化基序，作为识别探针。将靶DNA引入系统后，其一部分与识别探针的5'端互补，导致稳定的双链体连接，靶DNA的未结合部分充当了DNA酶的一个结合臂。 。这种包含完整的10-23 DNAzyme结构的双链体可以裂解发夹底物的嘌呤-嘧啶裂解位点，从而导致发夹结构断裂并释放出两个单链核酸，其中一个被生物素化并发挥了作用作为信号探针。使用生物素作为信号探针中的示踪剂，而链霉亲和素碱性磷酸酶（SA-ALP）作为报告分子，固定化的硫醇化捕获探针可以与信号探针结合。通过测量磷酸1-萘酯的酶促去磷酸化5分钟后产生的1-萘酚的量，通过伏安法测定固定化酶的活性。结果表明，该传感器在100fM至1nM的浓度范围内对幽门螺杆菌的互补靶序列表现出敏感的反应，检测极限为50fM。另外，传感系统可以以高灵敏度和可重用性来区分互补序列和错配序列。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号