基于压电谐振检测技术的癌胚抗原免疫传感器的实验研究

Experimental Studies of Carcino-embryonic Antigen Immunosensor Based on Piezoelectric Resonante Technology of Quartz Crystal

为了建立一种新型压电石英晶体癌胚抗原（CEA）免疫传感器，传感器检测池用AT切向、基频10MHz的石英晶体通过金属夹具和乳胶套圈固定组成，采用巯基化方法把抗人CEA单克隆抗体固定在金膜电极表面制成抗体敏感膜，构成的压电CEA免疫传感器应用于临床检测。实验结果显示：构建的压电CEA免疫传感器对CEA的响应特性良好，其线性检测范围为1．56～50．00ng／ml，甲胎蛋白（AFP）、前列腺特异抗原（PSA）、人绒毛膜促性腺激素（hCG）等对CEA的检测基本无干扰；传感器可再生后重复使用5次；50例临床标本检测结果与放射免疫检测法符合（P〉0．05），两种方法的相关系数为0．90。研制的压电CEA免疫传感器具有灵敏度高、特异性好、不需标记、操作简单、省时、能实时在线检测和重复使用等优点，对比分析表明其检测结果准确、可靠，可用于临床检验。

In order to construct a new type of piezoelectric quartz immunosensor for the determination of carcino-embryonic antigen （CEA）, the sensor detection pools were consisted of plastic loops and crystals that were 10 MHz quartz AT-cut with gold coated electrodes and the immobilization of the monoclonal antibody against CEA onto gold electrode surface of the quartz crystal was accomplished via Thiol method. Then the immunosensors were used in clinical laboratory. The experimental results showed that the piezoelectric immunosensor had good response to CEA, the frequency shifts were linearly dependent on CEA concentration in the range of 1.56- 50.00 ng/ml, other antigens such as alpha fetoprotein （AFP）, prostate specific antigen （PSA）, human chorionic gonadotropin （hCG） did not interfere with the sensor＇s response. The results obtained from this method were in satisfactory accordance with those obtained by radio immunoassay（P〉0.05）,The correlation coefficient was 0.90. Piezoelectric immunosensor for determination of CEA has the advanfage of high sensitivity, high specificity, unnecessary labeling, simple performing, rapid analysis, low cost, real-time detection and repeated use, etc. It can be used for detecting serum CEA in clinical laboratory.