液晶传感分析检测技术用于有机磷农药残留实时检测的研究

Real-time detection of organophosphorus pesticides (OPs) residues has attracted great attentions, because OPs are highly toxic and the easy left over results in serious food safety and health problems. Currently, the available real-time detections of OPs are commonly based on the enzyme inhibition (mainly acetylcholinesterase). This requires the detections occurring at the specific conditions such as at the specific temperature, that limits their applications. Therefore, there is a strong demand for a reliable and portable method of monitoring and reporting the appearance of OPs residues. Liquid crystals (LCs), having the properties of both solids and liquids, can report the chemical and biomolecular binding events through orientational behaviors and corresponding optical textures of LCs. Because it is easy to build up and the readout is observative by naked eyes, LC-based sensing shows great potentials in many applications. This project is, therefore, to develop LC-based analytical techniques and methods to detect OPs residues in a sensitive, reliable and portable way. Here, employing the principle of competitive coordination of LCs and OPs with metal salts, we will fist optimize the recognition probes for different OPs such as P=O and P=S through the computational chemistry. Furthermore, we will try to design a series of sensing units for different OPs, and to build up a LC-based assay of OPs detection with high sensitivity and selectivity, and in a simultaneous way. Also, we will further explore the quantitative method of LC-based sensing for OPs through microfabrication and microfluidics. Thus, a LC-based assay for OPs analysis will be developed through this project. The theoretical and experimental strategies explored here will provide insights for the design of LC-based detection for other organic pollutants. These are useful in food safety, environmental monitoring and other fields.

有机磷农药（Organophosphorus pesticides, OPs）残留造成了严重的食品污染和大众健康问题。开发实时便携的OPs残留检测技术意义重大。而当前的快速检测受严苛的酶抑制等生物反应条件限制。兼具液-固两相特性的液晶（Liquid Crystals, LCs），能放大化学/生物结合事件并将其转换成光学信号，是一类新兴的传感技术。本项目，旨在探索发展快速、便携、无能耗、结果目视可测的液晶分析检测技术用于OPs残留的实时检测。本项目拟结合LCs、OPs与金属离子发生竞争配合反应的机理，首先应用计算化学，优化出不同OPs的识别探针；进而，设计出一系列高灵敏的OPs检测敏感膜，实现同时高选择性分析不同OPs；并进一步结合微制造技术，探索OPs的量化分析方法。从而设计出像温度计一样准确、便携的OPs液晶分析检测装置。该项目研究也将为用液晶分析检测其它污染物提供有价值的指导。

研究开发快速便携的有机磷农药残留检测技术具有重要的意义。本项目的研究内容包括：以不同金属阳离子为探针的液晶、金属盐和有机磷分子间识别规律的研究；依据建立的识别规律，设计有机磷高灵敏度检测敏感元件及高通量液晶检测芯片的研究；以及对液晶分析检测量化方法的探索研究。在顺利完成了上述研究计划的基础上，项目负责人还以本项目发展建立的探针在功能化基底表面的固定技术为基础，开展了基于这种表面功能化修饰方法在纳米颗粒上的修饰及生物分子固定用于纳米佐剂的开发研究。本项目的研究为新型、高灵敏的液晶传感器构建提供新的理论基础和科学依据，为其在农药残留等污染物或毒素的快速检测技术开发提供有价值的指导，对促进上述分子的快速检测在食品安全和环境监测中的应用奠定了科学基础。