Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Biosens Bioelectron. 2012 Feb 15;32(1):288-92. doi: 10.1016/j.bios.2011.12.008. Epub 2011 Dec 13.
A novel cholesterol biosensor was prepared based on gold nanoparticles-catalyzed luminol electrogenerated chemiluminescence (ECL). Firstly, l-cysteine-reduced graphene oxide composites were modified on the surface of a glassy carbon electrode. Then, gold nanoparticles (AuNPs) were self-assembled on it. Subsequently, cholesterol oxidase (ChOx) was adsorbed on the surface of AuNPs to construct a cholesterol biosensor. The stepwise fabrication processes were characterized with cyclic voltammetry and atomic force microscopy. The ECL behaviors of the biosensor were also investigated. It was found that AuNPs not only provided larger surface area for higher ChOx loading but also formed the nano-structured interface on the electrode surface to improve the analytical performance of the ECL biosensor for cholesterol. Besides, based on the efficient catalytic ability of AuNPs to luminol ECL, the response of the biosensor to cholesterol was linear range from 3.3 μM to 1.0 mM with a detection limit of 1.1 μM (S/N=3). In addition, the prepared ECL biosensor exhibited satisfying reproducibility, stability and selectivity. Taking into account the advantages of ECL, we confidently expect that ECL would have potential applications in biotechnology and clinical diagnosis.
基于金纳米粒子催化鲁米诺电致化学发光（ECL），制备了一种新型胆固醇生物传感器。首先，在玻碳电极表面修饰 l-半胱氨酸还原氧化石墨烯复合材料。然后，金纳米粒子（AuNPs）自组装在其表面。随后，将胆固醇氧化酶（ChOx）吸附在 AuNPs 表面上构建胆固醇生物传感器。通过循环伏安法和原子力显微镜对逐步制备过程进行了表征。还研究了生物传感器的 ECL 行为。结果发现，AuNPs 不仅提供了更大的表面积以实现更高的 ChOx 负载量，而且还在电极表面上形成了纳米结构界面，从而提高了胆固醇的 ECL 生物传感器的分析性能。此外，基于 AuNPs 对鲁米诺 ECL 的高效催化能力，该生物传感器对胆固醇的响应呈现出从 3.3 μM 到 1.0 mM 的线性范围，检测限为 1.1 μM（S/N=3）。此外，所制备的 ECL 生物传感器表现出令人满意的重现性、稳定性和选择性。考虑到 ECL 的优势，我们有信心预计 ECL 将在生物技术和临床诊断中有潜在的应用。
