ACS Appl Mater Interfaces. 2019 Apr 3;11(13):12986-12992. doi: 10.1021/acsami.9b00693. Epub 2019 Mar 21.
Two-dimensional (2D) nanomaterials are remarkably attractive platform candidates for signal transduction through fluorescence resonance energy transfer or photo-induced electron-transfer pathway. In this work, a 2D Hofmann metal organic framework (hMOF) monolayer nanosheet was developed as an axial coordination platform for DNA detection via a ligand-to-metal charge-transfer quenching mechanism. Through modulating the position of phosphonate groups of rigid ligands, a layer-structured hMOF was synthesized. The single crystals showed that the adjacent layers were linked via hydrogen bonds between diethyl 4-pyridylphosphonate and the solvent. Furthermore, the 2D hMOF monolayer nanosheets were obtained easily via a top-down method. More significantly, the quenching mechanism was identified as an axial coordination between the open Fe sites of hMOF nanosheets and fluorophores with 91% quenching efficiency, constituting an excellent signal transduction strategy. The smart use of hMOF monolayer nanosheets as an axial coordination platform could lead to promising applications in signal switching or/and sensing devices.
二维（2D）纳米材料是通过荧光共振能量转移或光诱导电子转移途径进行信号转导的极具吸引力的平台候选材料。在这项工作中，二维霍夫曼金属有机骨架（hMOF）单层纳米片被开发为通过配体到金属电荷转移猝灭机制用于 DNA 检测的轴向配位平台。通过调节刚性配体中膦酸酯基团的位置，合成了层状 hMOF。单晶表明，相邻层通过二乙基 4-吡啶基膦酸酯和溶剂之间的氢键连接。此外，通过自上而下的方法很容易获得二维 hMOF 单层纳米片。更重要的是，猝灭机制被确定为 hMOF 纳米片的开放 Fe 位与荧光团之间的轴向配位，猝灭效率达到 91%，构成了出色的信号转导策略。明智地利用 hMOF 单层纳米片作为轴向配位平台，可在信号开关或/和传感设备中得到有前途的应用。
