摘要：将血红素通过轴向配位非共价组装在氮掺杂石墨烯上，与信号抗体共价相连而赋予该纳米复合物特异性识别功能，获得模拟酶特性的仿生催化探针。氮掺杂石墨烯大量负载的血红素提高了电催化活性。通过在玻碳电极表面修饰双齿螯合CdTe量子点(QDs)和捕获抗体，构建了电致化学发光(ECL)免疫传感器。由于双抗夹心免疫复合物的形成，氮掺杂石墨烯支持的血红素经四电子途径高效电催化还原溶解氧，抑制了共反应剂H2O2的产生，从而猝灭ECL发光。猝灭的ECL强度可用于癌胚抗原的免疫检测，其线性范围为0.1 pg mL−1~10 ng mL−1，检测限为24.0 fg mL−1，该思路使低水平生物标志物的检测成为可能。64139

毕业论文关键词：电致化学发光；免疫分析；量子点；石墨烯；电催化氧还原；血红素铁卟啉

毕业设计说明书(论文)外文摘要

Title: Preparation of Porphyrin@Graphene as Biomimetic Nanoprobe for Quantum Dot-Based Electrochemiluminescent immunoassay

Abstract:

A novel oxygen reduction catalyst was designed via the noncovalent assembly of hemin on nitrogen-doped graphene. The as-prepared catalyst led to sensitive electrochemiluminescent (ECL) quenching of quantum dots (QDs) due to the annihilation of dissolved oxygen, the ECL coreactant, by its electrocatalytic reduction. Using the mimic with high loading of hemin as a signal tag of the secondary antibody, a novel ultrasensitive immunoassay method for biomarker detection was proposed. In air-saturated pH 8.0 buffer, the immunosensor constructed by a stepwise immobilization of bidentate-chelated CdTe QDs and capture antibody showed an intensive cathodic ECL irradiation, which could be scavenged upon the formation of the catalyst bound sandwich immunocomplex. Using carcinoembryonic antigen as a model analyte, the immunoassay method showed a linear range from 0.1 pg mL−1 to 10 ng mL−1 and a detection limit of 24 fg mL−1. The immunosensor exhibited good stability, acceptable fabrication reproducibility and practicability. The electrocatalytic reduction-based ECL quenching strategy provided a powerful avenue for design of ultrasensitive detection method, showing great promise for clinical application.

Keywords:

Electrochemiluminescence; Immunoassay; Quantum dots; Graphene; Electrocatalytic reduction; Hemin

目    录

第一章 绪论 01

1.1背景 01

1.2关于电致化学发光及量子点 01

1.2.1电致化学发光简介 01

1.2.2电致化学发光的原理过程 02

1.2.3量子点简介 02

1.3课题研究的发展成果 02

1.4课题研究内容及研究手段 03

1.4.1主要研究内容 03

1.4.2研究手段 03

第二章 卟啉@石墨烯仿生纳米探针的制备及其量子点电致化学发光免疫分析应用 04

2.1引言 04

2.2实验部分 06

2.2.1材料和试剂 06

2.2.2仪器设备 06

2.2.3量子点的合成 07

2.2.4血红素@氮掺杂石墨烯纳米复合物的制备 07

2.2.5血红素@氮掺杂石墨烯标记信号抗体的制备 07

2.2.6 ECL免疫传感器的构建和测量步骤