论文总字数：31436字

摘 要

癌症是威胁人类生命健康的重大疾病，肿瘤的早期检出具有重要意义，尽早得到确诊有助于癌症患者后续的成功治疗，肿瘤标志物高灵敏检测是肿瘤早期检测是一种重要的手段。丝网印刷技术是目前一种成熟的发展技术，基于丝网印刷技术的生物传感器，由于其制备方法简单，容易实现批量化生产，同时检测方法检测、灵敏度高，被广泛应用于各种生物样本的高灵敏检测。因此，制备用于肿瘤标志物检测的丝网印刷生物传感器，可以为肿瘤早期检测提供了新的发展方向。

本论文主要的研究内容有：含有三维多孔石墨烯气凝胶结构柔性电极的可控制备方法研究、基于柔性电极的特异性检测传感器可控制备方法研究、柔性电极的电化学信号对特定生物分子响应特性的研究。

（1）提出一种适用于电化学检测的柔性电极的设计思路与制备方法，并研究该柔性电极的电学性能。使用了三电极体系，采用PET膜作为芯片基底，在工作电极表面采用原位化学法还原氧化石墨烯(GO)制备三维石墨烯气凝胶(3D GA)，并修饰抗体作为检测电极。通过扫描电镜（SEM）观察可以发现GA膜表面丰富交错的褶皱结构与空隙结构。这一三维结构赋予电极极大的比表面积以及非常小的阻抗。

（2）在电极修饰上不同的成分（如GA、抗体等），使其变为可检测肿瘤标志物的柔性电极，并研究其电学性能。使用电化学阻抗法（EIS）对一种典型的肿瘤标志物(AFP)进行检测与分析，结果证明该芯片检测灵敏度优异，检测性较低、线性响应区间较大。检测过程中，选定的目标抗原通过抗原抗体特异性反应与工作电极表面的抗体反应结合，这一过程增大了工作电极的阻抗效应。根据交流阻抗的变化，可以推断出待测物中抗原的浓度。

关键词：丝网印刷电极，三维石墨烯，电化学阻抗法，癌症早期诊断

Abstract

Cancer is a major disease that threatens the health of human life. The early detection of tumor is of great significance. Early diagnosis is helpful for successful follow-up treatment of cancer patients. High sensitivity detection of tumor markers is an important means for early detection of tumors. Screen printing technology is a mature development technology. The biosensor based on screen printing technology is widely used in various biological samples because of its simple preparation method and easy mass production. Highly sensitive detection. Therefore, the preparation of screen-printed biosensors for tumor marker detection can provide a new development direction for early detection of tumors.

The main research contents of this thesis are: the controllable preparation method of flexible electrode with three-dimensional porous graphene aerogel structure, the control method of specific detection sensor based on flexible electrode, and the electrochemical signal of flexible electrode to specific biomolecule Research on response characteristics.

(1) A design idea and preparation method of a flexible electrode suitable for electrochemical detection are proposed, and the electrical properties of the flexible electrode are studied. A three-electrode system was used, and a PET film was used as a chip substrate. Three-dimensional graphene aerogel (3D GA) was prepared by in situ chemical reduction of graphene oxide (GO) on the surface of the working electrode, and the antibody was modified as a detection electrode. Scanning electron microscopy (SEM) observation revealed that the surface of the GA film was rich in staggered fold structure and void structure. This three-dimensional structure gives the electrode a very large specific surface area and a very small impedance.

(2) Different components (such as GA, antibody, etc.) in electrode modification, making it a flexible electrode capable of detecting tumor markers, and studying its electrical properties. The detection and analysis of a typical tumor marker (AFP) by electrochemical impedance spectroscopy (EIS) showed that the chip has excellent detection sensitivity, low detection and large linear response range. During the detection process, the selected target antigen is combined with the antibody reaction on the surface of the working electrode by an antigen-antibody specific reaction, which increases the impedance effect of the working electrode. Based on the change in the AC impedance, the concentration of the antigen in the analyte can be inferred.

KEY WORDS: screen-printed electrodes, three-dimensional graphene, electrochemical impedance spectroscopy, early diagnosis of cancer

目 录

摘 要 Ⅰ

Abstract Ⅱ

第一章 绪论 1

1.1 课题背景及研究的目的和意义 1

1.2 癌症早期检测诊断技术的发展概况 1

1.3肿瘤标志物在癌症早期检测诊断中的应用与发展 2

1.4丝网印刷电极在生物传感器上的应用 4

1.5石墨烯材料在癌症诊断中的应用 5

1.5.1基于二维石墨烯及其复合材料的生物检测 5

1.5.2基于三维石墨烯及其复合材料的电化学检测 6

1.6 本课题主要研究内容 7

第二章 丝网印刷电极的总体设计与制备 10

2.1丝网印刷电极的总体方案设计 10

2.1.1基底的选择 10

2.1.2电极结构的设计 10

2.1.3油墨的选择 12

2.2 SPE的制备 12

2.2.1 实验材料 12

.2.2实验设备： 13

2.2.3 SPE的制作步骤 13

2.2.4实验结果分析 14

2.3电极上三维石墨烯气凝胶的修饰 14

2.3.1实验材料 15

2.3.2实验设备 15

2.3.3石墨烯气凝胶修饰步骤 15

2.3.4实验分析 17

2.4抗体的修饰 17

2.4.1实验材料 17

2.4.2实验设备 17

2.4.3抗体修饰步骤 17

2.4.4实验分析 18

第三章 柔性电极的制备与表征 19

3.1实验材料与设备 19

3.1.1实验材料 19

3.1.2实验设备 19

3.2石墨烯修饰电极可行性检测 19

3.3 电极的电化学阻抗响应 20

3.3.1 EIS检测机理简介 20

3.3.2电极的初始阻抗响应 21

3.3.3石墨烯气凝胶修饰前后电极的阻抗响应对比 22

第四章 柔性电极对抗原的检测 24

4.1抗体孵育时间的探究 24

4.2抗体浓度的优化 24

4.3抗原抗体的特异反应 25

4.4对血液样本中的AFP进行检测 26

第五章 总结与展望 28

4.1工作总结 28

4.2工作展望 28

参考文献 30

致 谢 32