Wu Shuyao, Jiang Meijiao, Mao Hui, Zhao Nan, He Dongqing, Chen Qinan, Liu Daliang, Zhang Wei, Song Xi-Ming
Liaoning Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials, College of Chemistry, Liaoning University, Shenyang, 110036, China.
Anal Bioanal Chem. 2022 May;414(12):3593-3603. doi: 10.1007/s00216-022-03986-9. Epub 2022 Feb 26.
A simple and sensitive electrochemical cholesterol biosensor was fabricated based on ceramic-coated liposome (cerasome) and graphene quantum dots (GQDs) with good conductivity. The cerasome consists of a lipid-bilayer membrane and a ceramic surface as a soft biomimetic interface, and the mild layer-by-layer self-assembled method as the immobilization strategy on the surface of the modified electrode was used, which can provide good biocompatibility to maintain the biological activity of cholesterol oxidase (ChOx). The GQDs promoted electron transport between the enzyme and the electrode more effectively. The structure of the cerasome-forming lipid was characterized by Fourier transform infrared (FT-IR). The morphology and characteristics of the cerasome and GQDs were characterized by transmission electron microscopy (TEM), zeta potential, photoluminescence spectra (PL), etc. The proposed biosensors revealed excellent catalytic performance to cholesterol with a linear concentration range of 16.0 × 10-6.186 × 10 mol/L, with a low detection limit (LOD) of 5.0 × 10 mol/L. The Michaelis-Menten constant (K) of ChOx was 5.46 mmol/L, indicating that the immobilized ChOx on the PEI/GQDs/PEI/cerasome-modified electrode has a good affinity to cholesterol. Moreover, the as-fabricated electrochemical biosensor exhibited good stability, anti-interference ability, and practical application for cholesterol detection.
基于具有良好导电性的陶瓷包覆脂质体（cerasome）和石墨烯量子点（GQDs）制备了一种简单灵敏的电化学胆固醇生物传感器。Cerasome由脂质双分子层膜和作为软仿生界面的陶瓷表面组成，并采用温和的层层自组装方法作为固定策略修饰电极表面，该方法能提供良好的生物相容性以维持胆固醇氧化酶（ChOx）的生物活性。GQDs更有效地促进了酶与电极之间的电子传递。通过傅里叶变换红外光谱（FT-IR）对形成cerasome的脂质结构进行了表征。通过透射电子显微镜（TEM）、zeta电位、光致发光光谱（PL）等对cerasome和GQDs的形态和特性进行了表征。所提出的生物传感器对胆固醇具有优异的催化性能，线性浓度范围为16.0×10⁻⁶～1.86×10⁻⁵mol/L，检测限低至5.0×10⁻⁶mol/L。ChOx的米氏常数（K）为5.46mmol/L，表明固定在PEI/GQDs/PEI/cerasome修饰电极上的ChOx对胆固醇具有良好的亲和力。此外，所制备的电化学生物传感器在胆固醇检测方面表现出良好的稳定性、抗干扰能力和实际应用价值。
