National Center for International Research of Biological Targeting Diagnosis and Therapy, Guangxi Key Laboratory of Biological Targeting Diagnosis and Therapy Research, Collaborative Innovation Center for Targeting Tumor Diagnosis and Therapy, Guangxi Medical University, Nanning, Guangxi 530021, China; School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, Guangxi 541004, China.
National Center for International Research of Biological Targeting Diagnosis and Therapy, Guangxi Key Laboratory of Biological Targeting Diagnosis and Therapy Research, Collaborative Innovation Center for Targeting Tumor Diagnosis and Therapy, Guangxi Medical University, Nanning, Guangxi 530021, China.
Biosens Bioelectron. 2018 Apr 15;102:560-567. doi: 10.1016/j.bios.2017.11.037. Epub 2017 Nov 11.
Cholesterol is an essential ingredient in mammals, and serum cholesterol is a major component of atherosclerotic plaques. The level of cholesterol in human serum has become an important index for clinical diagnosis and prevention of cardiovascular disease. In this paper, a simple and ultrasensitive cholesterol biosensor based on graphene oxide (GO) and gold nanoparticles (Au NPs) co-mediated enzymatic silver deposition was designed by immobilizing cholesterol oxidase (CHOD), cholesterol esterase (CHER) and GO onto the surface of Au NPs modified screen-printed carbon electrode (SPE). Under the synergistic effect of CHER, CHOD and GO, the cholesterol was hydrolyzed to generate hydrogen peroxide, which can reduce the silver (Ag) ions in the solution to metallic Ag which deposited on the surface of Au NPs modified SPE. The ultrasensitive detection of cholesterol was achieved by anodic stripping voltammetry measurement of the enzymatically deposited Ag. Under optimal conditions, the anodic stripping peak current of Ag increased with the increasing cholesterol concentration in the range from 0.01μg/mL to 5000μg/mL with a limit of detection of 0.001μg/mL (S/N = 3). In addition, the ultrasensitive cholesterol biosensor exhibited higher specificity, acceptable reproducibility and excellent recoveries for cholesterol detection.
胆固醇是哺乳动物体内必需的成分，血清胆固醇是动脉粥样硬化斑块的主要组成部分。人体血清中的胆固醇水平已成为临床诊断和预防心血管疾病的重要指标。本文设计了一种基于氧化石墨烯（GO）和金纳米粒子（Au NPs）协同酶促银沉积的简单、超灵敏胆固醇生物传感器，通过将胆固醇氧化酶（CHOD）、胆固醇酯酶（CHER）和 GO 固定在 Au NPs 修饰的丝网印刷碳电极（SPE）表面来实现。在 CHER、CHOD 和 GO 的协同作用下，胆固醇被水解生成过氧化氢，后者可以将溶液中的银（Ag）离子还原为沉积在 Au NPs 修饰 SPE 表面的金属 Ag。通过对酶促沉积的 Ag 的阳极溶出伏安法测量来实现胆固醇的超灵敏检测。在最佳条件下，Ag 的阳极溶出峰电流随着胆固醇浓度在 0.01μg/mL 至 5000μg/mL 范围内的增加而增加，检测限为 0.001μg/mL（S/N = 3）。此外，该超灵敏胆固醇生物传感器在胆固醇检测方面表现出较高的特异性、可接受的重现性和优异的回收率。
