新型半导体纳米晶复合材料在高灵敏电致化学发光肿瘤细胞检测中的应用研究

Cancer is a global medical problem. It originates from genetic abnormalities that usually cause the affected cells to behave differently at molecular level. The best way to cure cancer is early diagnosis and early treatment. Therefore, the development of novel detecting methods of cancer diseases with high sensitivity and specificity has a great significance. This study is carried out to build a novel highly-sensitive semiconductor nanocrystals (SNCs) electrochemiluminescence (ECL) biosensor and study its application in cancer cells detection. Combining the advantages of low cost, wide range of analytes, low background signal and high sensitivity of SNCs ECL, with the merits of high target affinity and specificity of cell aptamers, the SNCs-ECL biosensors are expected to show excellent performances in assay of cancer diseases. The main work could be divided into the following three aspects: (1)the study of new, high-quality SNCs-composite with ECL activity and the development of higher sensitive ECL biosensor using above SNC as a probe for cancer analysis; (2) the study of the ECL enhancement by the ECL-induced surface plasmon resonance of Au NPs. Optimizing the key experimental parameters, the greatest enhanced SNCs-ECL biosensors could be obtained under the optimal experimental conditions; (3) combined the selective recognition of cell aptamers, with the isothermal amplification technology of DNA enzymes, cancer cells are smartly assayed via signal-amplified DNA detection. The strategy of signal amplification avoids false positive detection results as well as improves the detecting sensitivity.

癌症是全球性医学难题，防治癌症的最好办法是早期诊断、早期治疗，因此，发展新型的高灵敏特异性的肿瘤检测方法对于癌症的早期发现及治疗具有重大的实际意义。本研究将半导体纳米晶（SNCs）电致化学发光（ECL）的灵敏度高、不需要外加激发光源、背景信号低、可进行原位现场分析、动态范围宽等优点与细胞适配体高亲和性、高特异性特点相结合，拟开展构建新型高灵敏SNCs-ECL生物传感器并将其用于肿瘤细胞的检测研究。主要工作分为以下几个方面：（1）开发制备新型的、具有ECL活性的高性能SNCs复合材料作为ECL信号探针以提高ECL生物传感分析的灵敏度；（2）研究金纳米粒子增强SNCs-ECL的决定因素，优化实验条件，提高对ECL的增强；（3）结合细胞适配体的选择识别作用与工具酶的等温循环放大技术，将对肿瘤细胞的检测转化为DNA的信号放大检测，既避免检测中的假阳性现象，又提高了检测的灵敏度。

癌症是全球性医学难题，防治癌症的最好办法是早期诊断、早期治疗，因此，发展新型的高灵敏特异性的肿瘤检测方法对于癌症的早期发现及治疗具有重大的实际意义。本项目以癌症早期诊断为导向，针对目前癌症早期诊断技术存在的问题，通过构建高灵敏、高特异性的纳米识别探针，发展光电肿瘤标志物检测新体系，结合工具酶循环放大作用，建立特异性好、灵敏度高的肿瘤标志物放大检测传感新方法和新技术，实现复杂生物体系中微量或痕量的肿瘤标志物的检测，克服了常规生物传感分析交叉干扰的影响，对于癌症的早期诊断和治疗具有非常重要的科学意义和临床价值。