压电免疫传感器两种抗体固定方法的比较研究

Two Antibody Immobilization Methods onto the Surfaces of Piezoelectric Quartz Immunosensor: A Comparative Study

目的 比较压电免疫传感器两种抗体固定方法的优劣 ,选择压电免疫传感器抗体敏感膜固定的最佳方法。方法 分别采用巯基化方法和蛋白 A(SPA )固定法将抗人胰岛素单克隆抗体固定在压电免疫传感器金膜电极表面 ,比较不同抗体工作浓度、不同浓度标准溶液反应条件下抗体固定量、一致性以及传感器响应能力如频率变化、反应时间、检测线性范围以及反应非特异性等。结果 两种固定方法制备的压电免疫传感器其检测灵敏度、反应时间相当 ,但巯基化固定方法抗体固定量大、一致性好、检测线性范围较宽、非特异反应低。结论 抗体巯基化法制备的压电免疫传感器具有检测范围宽、非特异反应低等优点 ,是免疫传感器抗体敏感膜制备的理想方法。

OBJECTIVETo make comparison between the two methods for immobilizing antibody onto the surfaces of piezoelectric quartz immunosensor and select the best one for the antibody membrane of piezoelectric quartz immunosensor. METHODSHuman insulin monoclonal antibody was immobilized onto the gold surfaces of piezoelectric quartz immunosensor with thiol method and protein A (SPA) method, respectively. The amount and coherence of immobilized antibody, the changes in frequency, time-cost and nonspecific reactions were compared in reactions with different concentrations of insulin and other antigens. RESULTS The sensitivity and time-cost were comparative. The thiol method immobilized more antibody, the immobilized antibody was conforming and hence the immunosensor could detect wide range of insulin concentrations, nonspecific reactivity was lower than that by SPA method. CONCLUSIONS The piezoelectric quartz immunosensor prepared by thiol method has the features of wide detection range and low nonspecific reaction. Therefore, thiol method is a good one for immobilizing antibody onto the surfaces of piezoelectric quartz immunosensors.