基于核酸适配体/纳米金粒子修饰石英毛细管的在线循环流动式管内固相微萃取技术及其应用研究

本项目拟将亲合力高、特异性强的核酸适配体生物识别体系应用于样品前处理技术，在一段长的空心石英毛细管内壁修饰纳米金粒子，通过巯金键将核酸适配体键合至纳米金粒子表面，增强键合强度及密度，提高适配体键合量及萃取容量；该毛细管连接蠕动泵、样品池及闭合管路实现循环流动式管内固相微萃取，提高样品萃取效率；同时通过六通阀搭建管内固相微萃取在线样品前处理装置，与高效液相色谱联用，实现在线萃取、解吸、进样及清洗，加快分析速度，提高工作效率，从而建立基于核酸适配体/纳米金粒子修饰石英毛细管的在线循环流动式管内固相微萃取技术，并应用于复杂生物样品中痕量、超痕量腺苷、三磷酸腺苷、茶碱等核苷酸或生物碱类物质快速、高效、高选择性分离富集与检测。

In this project, nucleic acid aptamer with high affinity and specificity would be adopted in sample pretreatment technique. A long hollow quartz capillary tube is modified with gold nanoparticles on the inner wall, and then aptamer is coated on the gold nanoparticle surface through Au-S chemical bonding to enhance the bonding strength and density. Consequently, the amount of bonded aptamer and the extraction capacity would be improved. Subsequently, the tube would be connected with a peristaltic pump, a sample cell and a closed circuit to perform the circulation flow in-tube solid-phase microextraction, and the sample extraction efficiency could be enhanced remarkably. Simultaneously, an on-line in-tube solid-phase microextraction device is set up with six-way valves and linked with liquid chromatography, so on-line extraction, desorption, sample injection and washing could be achieved, and fast analysis is realized and sample pretreatment efficiency could be enhanced. The on-line circulation flow in-tube solid-phase microextraction technique, based on nucleic acid aptamer/gold nanoparticle modified quartz capillary tube, would be established and applied to the fast, highly efficient and selective separation, enrichment, and detection of trace or ultra-trace nucleotides such as adenosine and adenosine triphosphatase and alkaloids such as theophylline in complex biological samples.