基于“动力学竞争”的普适型适配体比率传感新方法及分子作用机理研究

当前适配体传感器发展迅猛，但多数RNA适配体传感器的设计仍存在一定难度。其原因归咎于冗长的序列使其在优化和改进后很难再具备能够特异性识别其靶分子的二级结构。为此，申请人首次报道了普适的“动力学竞争”机制下的适配体传感新方法，不依赖于任何构象变化和反应平衡，解决了RNA适配体传感器设计难度高的问题。比率传感是近年来新型传感方法研究中的一个热点，能够避免传统检测法因外界因素而出现的假阳性结果。本课题拟将 “比率计”传感技术与“动力学竞争”模式下的传感体系有机结合，将生物毒素蓖麻毒素A链及其长链RNA适配体视为主要研究对象，创新构建多种基于“动力学竞争”普适型核酸适配体比率检测新技术。本研究主要致力于设计和优化“动力学竞争”体系的传感元素，借助“有酶”qPCR和“无酶”CHA反应等信号放大平台，提高检测的灵敏度，建立和完善“动力学竞争”体系的理论模型，为该机制的深入研发提供理论依据和应用基础。

Difficulty in design of most RNA aptasensors still exists despite the rapid development of aptasensors. The reason can be attributed to the secondary structure after optimization that is hard to bind the target specifically. Herein, the applicant, for the first time, reports a novel sensing strategy that works under “kinetic competition” mechanism, independent on conformation change or reaction equilibrium, simplifying the design of RNA aptasensor. Ratiometric sensing has been one of the hotspots in study of new sensing strategies because it can obliterate the false positive results brought by external factors in traditional sensing. Typically, ricin A chain and its long RNA aptamer are proposed to be our object of study for constructing various of general ratiometric sensors based on the novel “kinetic competition” mechanism. This proposal plans to design and optimize the sensing elements in “kinetic competition” system with the aid of qPCR and CHA amplification, enhancing the sensitivity of detection. The research will provide both theoretical basis and application foundation for further development of “kinetic competition” system by building and perfecting the theoretical model.