基于胱氨自组装膜的压电免疫传感器检测抗凝血酶Ⅲ  

Studies on a Piezoelectric Immunosensor Based on Self-assembled Monolayer of Cystaminc Dihydrochloride for Anti-thromin Ⅲ

作　　者：王存嫦[1,2] 王桦[1] 吴朝阳[1] 沈国励[1] 俞汝勤[1] 

机构地区：[1]湖南大学化学生物传感与计量学国家重点实验室,化学化工学院,长沙410082 [2]郴州师范高等专科学校,郴州423000

出　　处：《分析化学》2002年第9期1030-1034,共5页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金资助课题 (No .2 9975 0 0 6;2 0 0 75 0 0 6 )

摘　　要：提出了一种基于胱氨自组装膜和采用聚电解质吸附法固定活性物质的压电免疫传感器 ,用于检测人血浆中抗凝血酶Ⅲ (AT Ⅲ )。先在压电石英晶振的金电极表面自组装一层带巯基的胱氨单分子膜 ,再在膜上组装一层聚电解质褐藻酸钠 (AAS ) ,通过静电吸附作用 ,将AT Ⅲ抗体固定于石英晶体表面 ,在含有3 5 %聚乙二醇 (PEG )的缓冲溶液中检测AT Ⅲ。比较了传感器分别采用AAS吸附法和戊二醛键合法固定AT Ⅲ抗体的响应性能 ,发现前者固定的抗体的活性较高 ,反应响应的频移值较大 ,检测的线性范围也较宽。实验采用PEG作免疫反应的促进剂 ,进一步改善了传感器的检测灵敏度和检测限。采用Piranha试剂作洗脱液可实现传感器的反复再生。干扰与回收率实验结果表明 ,该传感系统可用于人血浆中AT Ⅲ的临床检测。A piezoelectric immunosensor based on a self-assembled monolayer of cystamine and polyelectrolyte adsorption technique has been developed for the determination of anti-thromin Ⅲ(AT-Ⅲ) in human plasma. The surface of quartz crystal microbalance (QCM) was firstly prepared with monomolecular films of cystaminc and then covered with a soluble polyelectrolyte alginic acid sodium ( AAS ) by self-assembling. Through strong electrostatic attraction, the opposite-charged antibody of AT-Ⅲ was incubated on the QCM by controlling the pH value lower than its isoelectric point. Subsequently, the determination of AT-Ⅲ was carried out in the buffer solution with 3 5% polyethylene glycol (PEG). Comparing to those by glutaraldehyde binding approach, AT-Ⅲ antibodies immobilized by AAS absorption method present more advantages of higher antibody activity, frequency response and linear range. In addition, a further improvement both in sensitivity and detection limit can be achieved by applying PEG as an immunoreaction-promoting solvent. Furthermore, the application of the Piranha solvent to repeatedly renew the contaminated crystal demonstrates satisfactory results. The tests of control and recovery imply that this immunosensor is a practical tool for detecting AT-Ⅲ in plasma in clinical diagnosis.

关 键 词：胱氨自组装膜 单分子自组装膜 聚电解质 压电免疫传感器 抗凝血酶Ⅲ 血浆 临床检测 

分 类 号：O657.1[理学—分析化学]