Coupling liquid crystal phase transitions with aptamer selectivity for biomolecular sensing

主要研究者：Tu，Raymond提案编号：1605904目标是使用具有特殊性质的生物材料来创建一种廉价且灵活的生物传感器，用于快速识别有害毒素和癌症生物标志物。 液晶与电视和手表中的结构相同，可用作超灵敏开关，用于将传感现象可视化。 综上所述，预计将创建一种新的设备，用于快速检测多种疾病生物标志物。这项工作将研究一种低成本的无标记传感技术，该技术专注于可以快速诊断贫困人群中流行的疾病和毒素的分析物。 研究人员的目标是通过将液晶的合作相变与基于适体的分析物结合的灵活性相结合来实现这一目标。 基于液晶的生物传感器便宜且灵敏，但是垂直于平面的相变的无标记应用需要改变介晶的界面堆积，从而将应用限制于窄范围的目标。 相比之下，适体具有选择性结合广泛的分析物的能力，并且使用指数式配体系统进化（SELEX）富集快速进化新靶标的能力使得核酸识别元件成为传感界的热门话题。 然而，挑战仍然是将这种容易进化的选择性转化为廉价的无标记“适体传感器”。“这项工作的目标是研究基本的界面科学和适体序列空间，这些空间需要将液晶-水界面与适体的选择性和灵敏度牢固地结合起来。 我们的方法，创造一个“generalizable”适体液晶系统调查在拟议的工作，四个基本方面的传感系统。 (1)发展一种定量的方法来评估竞争性吸附的液晶-水界面。 (2)当液体响应表面活性剂、未结合的适体和结合的适体时，测量表面能的变化并建模。 (3)确定实际传感器设计的速率限制步骤，其中相变动力学不应需要延长扩散或吸附时间。 (4)开发用于适体选择性以及适体与液晶和表面活性剂相互作用的演变的工具。

PI: Tu, Raymond Proposal Number: 1605904The goal is to create an inexpensive and flexible biosensor using biological materials of special properties for the rapid recognition of harmful toxins and cancer biomarkers. Liquid crystals, the same structures that are in TVs and watches, can be used as an ultra-sensitive switch for visualizing the sensing phenomena. Taken together, a new device is expected to be created for the rapid detection of numerous disease biomarkers.This work will investigate a low-cost label-free sensing technology that focuses on analytes that can quickly diagnose illnesses and toxins prevalent in impoverished populations. The researchers aim to accomplish this by combining the cooperative phase transitions of liquid crystals with the flexibility of aptamer-based analyte binding. Liquid crystal based biosensors are inexpensive and sensitive, but the label-free application of the homeotropic to planar phase change requires a change in the interfacial packing of the nematic mesogen, restricting applications to a narrow range of targets. In contrast, aptamers possess the ability to selectively bind to a wide range of analytes, and the ability to quickly evolve new targets using Systematic Evolution of Ligands by EXponential (SELEX) enrichment has made the nucleic acid recognition elements a popular topic in the sensing community. Still, the challenge remains to translate this easily evolvable selectivity into an inexpensive label-free "aptasensor." The goal of this work is to examine the fundamental interfacial science and aptamer sequence space needed to robustly couple the nematic liquid crystal-aqueous interface with aptamer selectivity and sensitivity. Our approach for creating a "generalizable" aptamer-liquid crystal system investigates in the proposed work, four fundamental aspects of the sensing system. (1) Develop a quantitative methodology for the evaluation of competitive adsorption to the nematic liquid crystal-aqueous interface. (2) Measure and model the change in surface energy as the liquid responds to surfactants, unbound aptamers and bound aptamers. (3) Determine the rate limiting steps for realistic sensor design, where the kinetics of the phase transition should not require protracted diffusive or adsorption times. (4) Develop tools for the evolution of both the aptamer selectivity as well as the aptamer interaction with the liquid crystal and surfactants.