新型多功能量热式生物传感器系统研究与开发

Research and development of a new versatile thermal biosensor

通过新型结构与流路设计,开发了量热式生物传感器,是由恒流泵、切换阀、恒温器、锥形注入阀、反应室和参比室、热电堆、信号采集模块和微机等组成的流动注射分析系统,能够工作在单向和循环模式。恒温器在0～70℃内有效控温,精度为±0.1℃;锥型注入阀实现绝热状态的同步进样;设置参比室有效消除非特异性热;片状热电堆的灵敏度约4 mV/K,并布置在反应室和参比室间,及时感知热信号变化;微弱信号采集模块具备24位分辨率和64倍增益,并利用虚拟仪器技术通过微机进行数据的动态显示、处理和存储;系统能够优化反应室尺寸、载流流速、反应温度和试剂注入量等关键参数。性能测试和多种反应模式研究表明,系统基线稳定、重现性好,并实现了酶分析、底物测试和重金属检测等功能,该系统尤其适用于抑制条件下的多试样、多组合的现场和在线富集、检测。

A versatile thermal biosensor is developed based on an improved design. This biosensor is a flow injection analysis system, which consists of a peristaltic pump, two switching valves, a thermostat, a cone-shaped injection valve, a reaction chamber, a reference chamber, a thermopile, a data acquisition module and a PC （Personal Computer）. The thermostat has an adjustable range of 0 -70℃ and precision of ＋0.1℃, the injection valve works under adiabatic condition, the thermopile has a sensitivity of 4mV/K and is placed between the reaction chamber and reference chamber for responding heat timely, an identical reference chamber is used for eliminating the unspecific heat, the data acquisition module for weak signal has 24 bit resolution and a gain of 64, and the PC integrated with virtual instrument can automatically display, process and store data in real time. The system can optimize the key parameters, such as sizes of reaction chamber and reference chamber, flux, reaction temperature and sample size. Performance tests demonstrate the advantages of the system, such as stable baseline, good repeatability, meanwhile realize the functions of enzyme assay, analyte determination and heavy metal detection. This biosensor is suitable for multi-sample or multi-component detection under inhibition condition in the fields of on-line and on-site monitoring.