Sekretaryova Alina N, Beni Valerio, Eriksson Mats, Karyakin Arkady A, Turner Anthony P F, Vagin Mikhail Yu
Department of Physics, Chemistry and Biology, Linköping University , SE-581 83 Linköping, Sweden.
Anal Chem. 2014 Oct 7;86(19):9540-7. doi: 10.1021/ac501699p. Epub 2014 Sep 10.
Monitoring the cholesterol level is of great importance, especially for people with high risk of developing heart disease. Here we report on reagentless cholesterol detection in human plasma with a novel single-enzyme, membrane-free, self-powered biosensor, in which both cathodic and anodic bioelectrocatalytic reactions are powered by the same substrate. Cholesterol oxidase was immobilized in a sol-gel matrix on both the cathode and the anode. Hydrogen peroxide, a product of the enzymatic conversion of cholesterol, was electrocatalytically reduced, by the use of Prussian blue, at the cathode. In parallel, cholesterol oxidation catalyzed by mediated cholesterol oxidase occurred at the anode. The analytical performance was assessed for both electrode systems separately. The combination of the two electrodes, formed on high surface-area carbon cloth electrodes, resulted in a self-powered biosensor with enhanced sensitivity (26.0 mA M(-1) cm(-2)), compared to either of the two individual electrodes, and a dynamic range up to 4.1 mM cholesterol. Reagentless cholesterol detection with both electrochemical systems and with the self-powered biosensor was performed and the results were compared with the standard method of colorimetric cholesterol quantification.
监测胆固醇水平非常重要，尤其是对于有患心脏病高风险的人群。在此，我们报道了一种新型的单酶、无膜、自供电生物传感器用于检测人血浆中的无试剂胆固醇，其中阴极和阳极生物电催化反应均由同一底物提供动力。胆固醇氧化酶固定在阴极和阳极的溶胶 - 凝胶基质中。胆固醇酶促转化的产物过氧化氢在阴极通过使用普鲁士蓝进行电催化还原。同时，在阳极发生由介导的胆固醇氧化酶催化的胆固醇氧化反应。分别对两个电极系统的分析性能进行了评估。在高表面积碳布电极上形成的两个电极组合，形成了一种自供电生物传感器，与两个单独电极中的任何一个相比，其灵敏度提高（26.0 mA M(-1) cm(-2)），动态范围高达4.1 mM胆固醇。使用两种电化学系统和自供电生物传感器进行了无试剂胆固醇检测，并将结果与比色法胆固醇定量的标准方法进行了比较。
