Real-time monitoring the level of nitric oxide (NO) secreted by living cells is crucial for understanding the pathological and physiological processes in human body and related diseases. In this study, the COF-366-Fe/GA was prepared by in situ growth of COF-366-Fe on 3D graphene aerogel (GA), which integrated the highly electrocatalytic property generated by COF-366-Fe and the 3D porous structure possessed by GA to build a unique sensing component for ultrasensitive and real-time determination of NO. Benefiting from the remarkable synergy effect between COF-366-Fe and 3D GA, the prepared biosensor presents ultrasensitive response in the wide range of 0.18 to 400 μM with a lower detection limit (30 nM) and higher sensitivity (8.8 μA·μM^-1·cm^-2). Moreover, the molecular signals could be immediately captured by the fabricated device after release of the gas messenger NO secreted by human umbilical vein endothelial cells. These results imply that the proposed COF-366-Fe/GA with precisely controllable active sites and 3D porous structure solves randomly arrangement problem of active sites for the nitrogen-coordinated electrocatalyst, which would provide a promising powerful platform for real-time analysis of biomarkers in clinical diagnostics.

实时监测活细胞分泌的一氧化氮（NO）的水平对于了解人体及相关疾病的病理和生理过程至关重要。在这项研究中，COF-366-Fe / GA是通过在3D石墨烯气凝胶（GA）上原位生长COF-366-Fe制备的，该气凝胶整合了COF-366-Fe和3D多孔结构产生的高度电催化性能由GA拥有，可构建用于超灵敏，实时测定NO的独特传感组件。得益于COF-366-Fe与3D GA的显着协同作用，制备的生物传感器在0.18至400μM的宽范围内表现出超灵敏响应，且检测限较低（30 nM），灵敏度较高（8.8μA·μM ^-1） ·厘米^-2）。此外，在释放由人脐静脉内皮细胞分泌的气体信使NO后，分子信号可以被所制造的装置立即捕获。这些结果表明，提出的具有精确可控活性位和3D多孔结构的COF-366-Fe / GA解决了氮配位电催化剂活性位随机排列的问题，这将为生物标记物的实时分析提供有希望的强大平台。在临床诊断中。