兼具电位分辨和空间分辨的电化学发光纳米生物传感新方法构建及分析应用研究

Electrochemiluminescent (ECL) bioanalysis has attracted great attentions due to its merits such as high sensitivity and wide linear range. However, the traditional ECL methods based on the change in a single detection signal, which may cause false-positive or false-negative results, especially in complex biological matrix. In addition, the single signal detection mode also limited the multiplexed detection. The objective of this project is to construct ECL biosensing platform with both potential and spatial-resolved features for accuracy and sensitive detection of bioactive molecules (e.g. PSA, CEA, miRNA-21). The platform is based on the excellent optical, electrical and catalytic properties of nonmaterials and highly specificity of aptamer and antibody. The main contents of this project are as follows: (1) the synthesis and characerization of layered transition-metal dichalcogenides and their composite materials with high loading capacity and fast electron transfer efficiency. (2) the synthesis, functionalization of the ECL emitters; the screening of the potential-resolved ECL system. (3) the design and assembly of microdevice with potential and spatial-resoved features and the fabrication of the developed sensing platform. (4) the methodology study and the application of the proposed method in real world samples analsysis, such as human serum and urine. The proposed method would be developed into a novel, accuracy, sensitive and multiplex methods for bioactive molecules analysis in complex biological systems and expected to apply in the early disease clinial diagonosis(e.g. prostate cancer).

电化学发光（ECL）具有灵敏度高、线性范围宽等优点而备受青睐。但目前的ECL方法主要基于单一信号强度进行分析，还存在两大局限：一是对于复杂体系，易产生假阳性或阴性错误；二是多元分析受到限制。本项目拟将电位分辨技术和空间分辨技术相结合，利用纳米材料优良的光、电和催化性能，发挥适配体、抗体的特异性识别作用，构建兼具电位分辨和空间分辨性能的ECL传感新平台及准确、灵敏、多元检测新技术。主要内容包括：（1）高负载、高电子传递效率的过渡金属二硫化合物纳米材料及其复合纳米材料的合成及表征；（2）新型ECL发光剂的合成、功能化修饰以及电位分辨型ECL体系的筛选；（3）兼具电位分辨和空间分辨性能的微器件设计、组装及传感平台构建；（4）开展方法学及人血清、尿样等分析应用研究。本项目将为复杂生物体系中活性分子（如PSA、CEA、miRNA-21）准确、灵敏、多元检测以及1-2种重大疾病早期诊断提供新方法。

高灵敏和选择性检测疾病标志物在疾病早期诊断中具有重要意义。电化学发光具有无需激发光源、背景信号低、灵敏度高、线性范围宽、可控性强等优点而受到重视，但目前的电化学发光检测方法主要基于单一信号强度进行分析，对于复杂体系，还存在易产生假阳性或阴性错误以及多元分析受到限制等的局限。近年来，纳米科学的快速发展为生物分子的灵敏检测开辟了新的途径，也为生物传感带来了新的机遇。本项目围绕兼具电位分辨和空间分辨的电化学发光纳米生物传感新方法构建及分析应用研究这一课题，合成了新型的电化学发光剂、高负载高电子传递效率的过渡金属二硫化合物纳米材料及其复合纳米材料，对纳米探针进行了功能化修饰，筛选了电位分辨型电化学发光体系，构建了兼具电位分辨和空间分辨性能的微器件及传感平台。结合适配体和抗原/抗体的特异性，借助共振能量转移、阴极和阳极的协同作用、电子供体生成/消耗等方法进行信号放大，发展了包括比率法在内的系列电化学发光检测单一或多种疾病标志物（如，前列腺特异性抗原PSA、癌胚抗原CEA、心肌梗死标志物心肌肌钙蛋白cTnI和肌红蛋白Myo）的高灵敏、高选择性新方法，检出限达超灵敏分析的pg/mL量级。此外，也提出了LNCaP细胞表面PSA的双极电极成像分析新技术，为肿瘤标志物及癌细胞的可视化检测提供了新方法。项目进展过程中，根据研究工作实际有所拓展，将光电化学检测巧妙融入有关体系中，发展了光电化学生物传感检测疾病标志物的新技术。与信阳市中心医院一道，将发展的新方法新技术成功应用于相关病人（如前列腺癌患者）早期诊断，结果与医院一致。项目的实施为疾病标志物的灵敏准确检测提供了电化学发光纳米生物传感分析新方法和新技术。