Cu 2 O-Mediated Heterojunction Conversion from Dual Type II to Dual Z-Scheme: Its Application in Photoelectric–Colorimetric Dual-Mode Detection of Fat Mass and Obesity-Associated (FTO) Protein

作者：Miao Zhang, Yunlei Zhou, Haowei Zhang, Huanshun Yin, Jingrui Duan, Shiyun Ai · 发表于：Analytical Chemistry · 年份：2024 · DOI：10.1021/acs.analchem.4c03951 · 被引用次数：29 · 研究领域：Advanced biosensing and bioanalysis techniques、Advanced Nanomaterials in Catalysis、Molecular Sensors and Ion Detection

Although the construction of heterojunction has been used in photoelectrochemical (PEC) biosensors, their potential for tunable optical properties has not been deeply explored. Based on the fact that a type-II heterojunction and Z-scheme heterojunction have the same energy band structure, effective alteration of the electron transfer pathway has been achieved by introducing unique photoactive materials into the system and exploiting the interactions between the photomaterials. Based on this, we reported a novel polarity-switchable dual-mode sensor for fat mass and obesity-associated (FTO) protein analysis. Specifically, the MgIn 2 S 4 /Bi 2 MoO 6 /Bi 2 S 3 dual type-II heterojunction was used as the sensing interface in concert with the rolling circle amplification, CRISPR/Cas12, and terminal DNA transfer enzyme multiamplification strategies, and finally, Cu 2 O was captured at the sensing interface. Due to the matched energy band, the introduction of Cu 2 O effectively changed the electron transfer pathway and realized the conversion from a dual type-II heterojunction to a dual Z-scheme heterojunction. It caused the switch of the photocurrent from the anode to the cathode. The developed PEC method showed high sensitivity and selectivity for FTO protein detection in the range of 0.0005–500 μg/L. In addition, based on the peroxidase-like activity of Cu 2 O to catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine by H 2 O 2, the electrode system also achieved the colorimetri...