Highly Light-Harvesting MOF-on-MOF Heterostructure: Cascading Functionality to Flexible Photogating of Organic Photoelectrochemical Transistor and Bienzyme Cascade Detection

作者：Xiaomei Shi, Zhen Wang, Miao-Hua Chen, Qingqing Wu, Feng‐Zao Chen, Gao‐Chao Fan, Weiwei Zhao · 发表于：Analytical Chemistry · 年份：2024 · DOI：10.1021/acs.analchem.4c00173 · 被引用次数：37 · 研究领域：Conducting polymers and applications、Electrochemical sensors and biosensors、Advanced biosensing and bioanalysis techniques

Recently, organic photoelectrochemical transistor (OPECT) bioanalysis has become a prominent technique for the high-performance detection of biomolecules. However, as a sensitive index of the OPECT, the dynamic regulation transconductance ( g m ) is still severely deficient. Herein, this work reports a new photosensitive metal–organic framework (MOF-on-MOF) heterostructure for the effective modulation of maximum g m and natural bienzyme interfacing toward choline detection. Specifically, the bidentate ligand MOF (b-MOF) was assembled onto the UiO-66 MOF (u-MOF) by a modular assembly method, which could facilitate the charge separation and generate enhanced photocurrents and offer a biophilic environment for the immobilization of choline oxidase (ChOx) and horseradish peroxidase (HRP) through hydrogen-bonded bridges. The transconductance of the OPECT could be flexibly altered by increased light intensity to maximal value at zero gate bias, and sensitive choline detection was achieved with a detection limit of 0.2 μM. This work reveals the potential of MOF-on-MOF heterostructures for futuristic optobioelectronics.