压电石英晶体甲胎蛋白免疫传感器的实验研究

Experimental study of alpha fetoprotein piezoelectric quartz crystal immunosensor

目的 构建一种新型压电甲胎蛋白 (AFP)免疫传感器。方法 AT切向、基频 10MHz的石英晶体用金属夹具和乳胶套圈固定组成检测池 ,抗人AFP单克隆抗体采用巯基化方法固定在金膜电极表面制成抗体敏感膜 ,构成压电AFP免疫传感器。结果 构建的压电AFP免疫传感器对AFP的响应特性良好 ,其线性检测范围为 2 0～ 10 0 0ng ml ,癌胚抗原(CEA)、前列腺特异抗原 (PSA)、人绒毛膜促性腺激素 (hCG)等对AFP的检测基本无干扰 ;传感器可再生后重复使用 5次 ;68例临床标本检测结果与放射免疫检测法符合 ,两种方法的相关系数为 0 92 ,P <0 0 1。结论 研制的压电AFP免疫传感器是一种灵敏度高、特异性好、不需标记、操作简单、省时、能重复使用和实时在线检测AFP的新方法 ,对比实验表明其检测结果准确 ,能用于临床实验诊断 ,具有临床推广价值。

Objective To construct a new type of alpha fetoprotein(AFP) piezoelectric quartz immunosensor for the determination of human AFP Methods The sensor detection pools consisted of plastic cycles and the crystals of 10 MHz quartz AT cut with gold coated electrodes The immobilization of the monoclonal antibody of AFP onto the gold electrode surface of the crystal was accomplished via Thiol method The immunosensors were used in clinical laboratory Results Experimental results showed that the piezoelectric immunosensor had good response to AFP The frequency shifts were linearly dependent on AFP concentration in the range of 20-1 000 ng/ml Other antigens such as carcino emrynic antigen(CEA), prostate specific antigen(PSA), human chorionic gonadotrophin(hCG) did not interfere with the sensor's response The analytical results given by this approach were in satisfactory agreement with those given by radiometric immunoassay The correlation coefficient was 0 92 Conclusion Piezoelectric immunosensor for determination of AFP is of high sensitivity, high specificity, unnecessary labelling, simple operation, high analysis speed, low cost, real time detection and repeated use, etc It may be suitable for the detection of AFP of serum in clinical laboratory