In this work, a heterojunction composite of HOFs/g-CN was synthesized using solution-plasticized self-assembly of g-CN nanosheet on hydrogen-bonded organic frameworks (HOFs). HOFs/g-CN was then used as a substrate material to construct a novel photoelectrochemical/electrochemiluminescent (PEC/ECL) biosensor for the detection of amyloid β oligomer (Aβo). HOFs/g-CN composites were first drop-coated on the electrode surface. Subsequently, the Aβ aptamer was modified on the electrode surface via amide bonding. The target Aβo and the gold nanorods (Au NRs)-labeled Aβ recognition peptide (Au NRs-KLVFF) were simultaneously dropped onto the electrode surface, thus a “sandwich” dual-mode biosensor was constructed. In the PEC detection of the Aβo, the surface plasmon resonance effect of Au NRs enhanced the visible absorption of HOF/g-CN, and the sensor exhibited a "signal-on" photocurrent signal. Meanwhile, the ECL emission spectrum of HOF/g-CN in ECL mode overlaps with the ultraviolet-visible (UV) absorption of Au NRs, and the sensor signal showed a “signal-off” ECL response. Under the optimal conditions experiments, the constructed dual-mode biosensor showed a wide detection range and low detection limit for Aβo. The proposed dual-mode detection method has a detection range of 10 fM to 10 nM with a detection limit of 5.97 fM for PEC detection and a detection range of 0.1 pM to 1.0 μM with a detection limit of 0.051 pM for ECL detection respectively. Additionally, the detection method achieved satisfactory results in the analysis of real samples. Dual-mode sensing platform provides a new strategy for HOFs application in PEC/ECL assay and sensitive detection of Aβ.

中文翻译：

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通过 HOFs/g-C3N4 Au NR 调制的光电化学/电化学发光响应对淀粉样蛋白 β 寡聚物进行超灵敏双模式检测


在这项工作中，利用氢键有机框架（HOF）上的g-CN纳米片的溶液增塑自组装合成了HOF/g-CN异质结复合材料。然后使用 HOFs/g-CN 作为基质材料构建了一种新型光电化学/电化学发光 (PEC/ECL) 生物传感器，用于检测淀粉样蛋白 β 寡聚物 (Aβo)。首先将 HOFs/g-CN 复合材料滴涂在电极表面上。随后，Aβ适体通过酰胺键在电极表面进行修饰。将目标Aβo和金纳米棒（Au NRs）标记的Aβ识别肽（Au NRs-KLVFF）同时滴到电极表面，从而构建了“三明治”双模式生物传感器。在Aβo的PEC检测中，Au NRs的表面等离子体共振效应增强了HOF/g-CN的可见光吸收，传感器表现出“信号开启”的光电流信号。同时，ECL模式下HOF/g-CN的ECL发射光谱与Au NRs的紫外-可见(UV)吸收重叠，传感器信号呈现“信号关闭”ECL响应。在最佳实验条件下，构建的双模式生物传感器对Aβo表现出较宽的检测范围和较低的检测限。所提出的双模式检测方法的PEC检测的检测范围为10fM至10nM，检测限为5.97fM；ECL检测的检测范围为0.1pM至1.0μM，检测限为0.051pM。此外，该检测方法在实际样品分析中取得了满意的结果。双模式传感平台为HOFs在PEC/ECL检测和Aβ灵敏检测中的应用提供了新策略。