Synthesis of Yolk/Shell heterostructures MOF@MOF as biomimetic sensing platform for catechol detection
Synthesis of Yolk/Shell heterostructures MOF@MOF as biomimetic sensing platform for catechol detection
复制标题
卵黄/壳异质结构的合成MOF@MOF作为儿茶酚检测的仿生传感平台
DOI：
10.1016/j.snb.2020.129133
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发表时间：
2021-01-17
影响因子：
8.4
通讯作者：
Wu, Lidong
中科院分区：
文献类型：
--
作者：
Cao, Qiang;Xiao, Yushi;Wu, Lidong
金属-有机骨架材料具有高比表面积、可调孔隙率、金属和官能团多样性等特点，具有作为多相仿生催化剂的潜力。然而，纯单体MOFs的活性和底物特异性仍有待提高。在这里，在仿生MOF的外表面上的尺寸选择性MOF涂层用于克服纯单体MOF的这些限制。该仿生材料的合成过程包括首先用聚乙烯吡咯烷酮（PVP）作为结构导向剂包覆多孔配位网络（PCN-222）核，然后对沸石咪唑骨架（ZIF-8）进行改性。基于蛋黄/壳PCN-222@ZIF-8的传感器显示出对儿茶酚的高选择性，但对多巴胺或L-DOPA没有。基于PCN-222@ZIF-8混合材料的传感器显示出比基于PCN-222的传感器高10倍的灵敏度，检测下限（LOD）为33 nmol L-1。因此，ZIF-8是一种壳，允许特定底物扩散到PCN-222的活性位点并富集底物。此外，PCN-222@ZIF-8具有溶剂适应性，克服了天然HRP酶的缺点。这项工作为构建MOF@MOF仿生传感器和其他应用开辟了新的途径。
Metal-organic frameworks (MOFs) have potential as heterogeneous biomimetic catalysts due to their high surface area, tunable porosity, and diversity of metals and functional groups. However, the activity and substrate specificity of pure monomeric MOFs still must be improved. Here, a size-selective MOF coating on the external surface of a biomimetic MOF is used to overcome these limitations of pure monomeric MOFs. The synthesis process of the biomimetic material involved first the coating of porous coordination network (PCN-222) cores with polyvinylpyrrolidone (PVP) as a structure-directing agent and then the modification of zeolitic imidazolate frameworks (ZIF-8). The yolk/shell PCN-222@ZIF-8-based sensor showed high selectivity for catechol but not for dopamine or L-DOPA. The PCN-222@ZIF-8 hybrid material-based sensor displayed 10 times more sensitivity than the PCN-222-based sensor, with low limit of detection (LOD) at 33 nmol L-1. Thus, ZIF-8 is a shell which allows the diffusion of specific substrate to the active sites of the PCN-222 and enriches the substrate. Furthermore, the PCN-222@ZIF-8 exhibits solvent adaptability, which overcomes the drawback of the natural HRP enzyme. This work opens a new avenue for construction of MOF@MOF biomimetic sensors and other applications.