基于功能化溶胶-凝胶膜的乳腺癌抗原免疫传感器

结合溶胶-凝胶(sol-gel)和交联技术,将乳腺癌抗体固定在铂盘电极表面的氨基化sol-gel功能膜上,制备出用于检测乳腺癌抗原(CA15-3)的免疫传感器.用红外光谱验证了该传感器功能膜的形成过程和组成结构,采用循环伏安法对传感器逐层修饰过程进行了表征,并对传感器功能膜的作用机理进行了探讨.该法检测CA15-3的线性范围为8～240U/mL,线性回归方程为ΔE=75.75lgc-56.36,r=0.998.结果表明,该方法很好地保持了被固定抗体的活性,增强了传感器的稳定性,所制备的传感器于4℃干态保存30d,其响应信号基本不变.且该传感器响应迅速、灵敏度高、选择性好,血清中常见抗原不干扰测定.

Breast Cancer Antigen Immunosensor Based on the Functional Sol-gel Film

A new type of non labeled immunosensor for the determination of breast cancer antigen(CA15 3) was made by combining sol gel with cross link techniques and utilizing glutaraldehyde(GA) to link CA15 3 antibody(Ab) on the functional sol gel film, so the sol gel/GA/Ab layer was immobilized on the surface of platinum disk electrode. Infrared spectrum(IR) and cyclic voltammetry(CV) were employed to investigate the structure and the electrochemical characteristics of the immunosensor, respectively. The linearity of CA15 3 in the range of 8—240 U/mL with a detection limit of 5 U/mL and the correlation coefficient of 0 998 are obtained. The experimental results show that the activity of the immobilized CA15 3 antibody is maintained better by this method, and the stability of the immunosensor is improved. The dependences of the potential response on pH, incubation time, sensitivity and reproducibility were studied, and the stability of the sensor was also evaluated. The immunosensor was found to be stable for about 30 days when stored in a dry state at 4 ℃. Satisfactory determination results of CA15 3 in serum samples were obtained by this method.