Cornell High Energy Synchrotron Source, Cornell University, Ithaca, New York, 14853, USA.
Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne-NE1 7RU, UK.
Sci Rep. 2019 Oct 29;9(1):15519. doi: 10.1038/s41598-019-51882-7.
State-of-the-art ultra-sensitive blood glucose-monitoring biosensors, based on glucose oxidase (GOx) covalently linked to a single layer graphene (SLG), will be a valuable next generation diagnostic tool for personal glycemic level management. We report here our observations of sensor matrix structure obtained using a multi-physics approach towards analysis of small-angle neutron scattering (SANS) on graphene-based biosensor functionalized with GOx under different pH conditions for various hierarchical GOx assemblies within SLG. We developed a methodology to separately extract the average shape of GOx molecules within the hierarchical assemblies. The modeling is able to resolve differences in the average GOx dimer structure and shows that treatment under different pH conditions lead to differences within the GOx at the dimer contact region with SLG. The coupling of different analysis methods and modeling approaches we developed in this study provides a universal approach to obtain detailed structural quantifications, for establishing robust structure-property relationships. This is an essential step to obtain an insight into the structure and function of the GOx-SLG interface for optimizing sensor performance.
基于葡萄糖氧化酶 (GOx) 共价连接到单层石墨烯 (SLG) 的最先进的超高灵敏度血糖监测生物传感器，将成为个人血糖水平管理的下一代有价值的诊断工具。我们在此报告使用多物理方法对不同 pH 值条件下 SLG 上 GOx 功能化的基于石墨烯的生物传感器的小角中子散射 (SANS) 进行分析，获得的传感器矩阵结构的观察结果。我们开发了一种方法来分别提取 SLG 内分级组装中 GOx 分子的平均形状。该模型能够分辨出 GOx 二聚体结构的平均差异，并表明在不同 pH 条件下处理会导致 GOx 在与 SLG 接触的二聚体区域内的差异。我们在这项研究中开发的不同分析方法和建模方法的结合为获得详细的结构量化提供了一种通用方法，以建立稳健的结构-性能关系。这是深入了解 GOx-SLG 界面的结构和功能以优化传感器性能的重要步骤。
