| 摘要: |
| 目的 设计一种基于AgI模拟酶纳米材料的阻抗型免疫传感器，对血清样品中的癌胚抗原（CEA）进行高灵敏检测。方法 合成一种壳聚糖修饰的碘化银（CS-AgI）纳米材料，利用透射电镜（TEM）和傅里叶红外光谱（FTIR）法对合成的CS-AgI 进行表征，以CS-AgI为信号标记物修饰CEA抗体，采用夹心式免疫分析法在金电极表面制备一种高效、灵敏的电化学免疫传感器，采用电化学工作站定量分析检测所构建免疫传感器的电化学性能。结果 成功合成CS-AgI纳米颗粒，颗粒呈球形，粒径约为100 nm。以CS-AgI纳米颗粒为信号标记物构建的免疫传感器在pH 7.0的磷酸盐缓冲液中检测CEA时表现出良好的电化学性能，其交流阻抗响应值与样品中的CEA浓度的对数呈线性增加趋势，并在 CEA浓度为0.1~80 ng/mL范围内展现出良好的线性关系（r=0.996），检测限达到0.05 ng/mL。结论 基于AgI模拟酶纳米材料构建的阻抗型免疫传感器可以高灵敏检测CEA，同时具有较好的精确性、重现性和选择性，为癌症的早期诊断和早期治疗提供了实验依据。 |
| 关键词: 生物传感技术 电化学免疫传感器 电阻抗 模拟酶 纳米粒子 壳聚糖 碘化银 癌胚抗原 |
| DOI：10.16781/j.0258-879x.2016.12.1533 |
| 投稿时间：2016-10-06修订日期：2016-12-07 |
| 基金项目:国家自然科学基金（50872086）. |
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| A novel impedimetric immunosensor based on AgI mimic enzyme nanomaterial for detecting carcinoembryonic antigen |
| ZHAO Yan-ling1\2,ZHANG Hui2,WANG Xiao-chun2,XIE Xian-mei1* |
(1. College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China;
2. Department of Medical Imaging, Shanxi Medical University, Taiyuan 030001, Shanxi, China
* Corresponding author) |
| Abstract: |
| Objective To design a novel impedimetric immunosensor based on AgI mimic enzyme nanomaterial for detecting carcinoembryonic antigen (CEA) in serum with high sensitivity. Methods A novel chitosan modified AgI (CS-AgI) nanomaterial was synthesized and was characterized by transmission electron microscope (TEM) and Fourier transform infrared spectroscopy (FTIR). Then by utilizing CS-AgI labeled CEA antibody as tags, we prepared a novel impedimetric immunosensor on the gold electrode using the sandwich-type immunoassay. The electrochemical properties of the prepared impedimetric immunosensor were observed by electrochemical workstation and the concentration of CEA in sample was quantitatively analyzed. Results The synthesized CS-AgI nanoparticles were spherical in shape, with the particle size being 100 nm; the particles were employed to construct immunosensor as signal markers. The immunosensor had an excellent electrochemical performance in detection of CEA under PBS base solution of pH=7, and its AC impedance response increased with the increase of the logarithm of CEA concentration, exhibiting a good linear relationship in the range of 0.1 ng/mL to 80 ng/mL (r=0.996), with a detection limit of 0.05 ng/mL. Conclusion Based on AgI mimic enzyme nanomaterial, the impedance immunosensor prepared in this study shows a high sensitivity in detecting CEA; meanwhile, it has acceptable selectivity, repeatability and stability, providing an experimental evidence for early diagnosis and treatment of cancer. |
| Key words: biosensing techniques electrochemical immunosensor electric impedance mimic enzyme nanoparticles chitosan silver iodide carcinoembryonic antigen |
