基于叉指微电极阵列和ATRP的肺癌microRNA高灵敏电检测

MicroRNA与肺癌发生和发展密切相关，因此可以作为诊断的生物标志物，但对其高灵敏定量检测仍是一个瓶颈问题。本项目拟构建一个简单快捷的微电极阵列平台，以实现对肺癌microRNA的高灵敏定量检测。在叉指微电极阵列器件上固定肽核酸为特异性探针，捕获样品中的肺癌microRNA，利用原子转移自由基聚合反应的信号放大作用在叉指微电极阵列表面原位聚合引入大量客体分子，然后通过主客体识别将大量主体分子功能化的金纳米粒子引入到器件表面，使得叉指电极间的电导率显著上升，根据电导率的变化，实现对痕量肺癌microRNA的高灵敏、高选择性电检测。另外，探讨该过程反应体系中分子间的相互作用和机理，研究不同因素对反应的影响并优化条件。该研究对于基于微电极阵列的电检测新方法的建立具有重要理论意义，而且在临床上对于肺癌microRNA的高灵敏检测提供一种可靠的方法，具有极大的应用价值。

MicroRNA has a close association with the occurrence and development of lung cancer, thus microRNA can be used as a kind of biomarker for its prediction and diagnosis. Unfortunately, to achieve highly sensitive quantitative detection of lung cancer is still a great challenge and bottleneck. The aim of this proposal is to build a quick and simple microelectrode array device platform for highly sensitive and quantitative detection of lung cancer microRNA. Peptide nucleic acid (PNA) acting as specific probes is immobilized onto interdigitated microelectrodes array to capture lung cancer microRNA in sample, then a great number of guest molecules will be introduced onto the surface of microelectrodes array via in-situ atom transfer radical polymerization (ATRP); and accordingly a large number of gold nanoparticles (AuNPs) functionalized with host molecules are imported to the sensing surface of interdigitated microelectrodes array through host-guest recognition, which results in a significant increase in conductivity between a pair of interdigitated array microelectrodes. According to the change of conductivity, trace microRNA can be detected with high sensitivity and specificity. Meanwhile, the molecular interaction and mechanism of this reaction system would be explored, and the influence of different factors on the reaction and optimal conditions would be studied. This proposal would be of great importance for the development of a novel electrical detection via microelectrode array; and provides an original approach to detect microRNA of lung cancer in clinical samples also, which will have great potential for practical application.