College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
Ministry of Education, Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Changsha, Hunan 410082, China.
Anal Chem. 2020 Oct 6;92(19):13073-13083. doi: 10.1021/acs.analchem.0c02002. Epub 2020 Sep 15.
Herein, we developed an unmodified hexagonal boron nitride (h-BN) photoelectrochemical (PEC) biosensing platform with a low background signal and high sensitivity based on CuS quantum dots (QDs)/CoO polyhedra-driven multiple signal amplifications. The prepared porous h-BN nanosheets with large specific surface areas, as the photoelectric substrate material, can provide extensive active reaction sites. Meanwhile, the CuS QDs/CoO polyhedra were synthesized by the zeolitic imidazolate framework (ZIF-67) and utilized as a multiple signal amplifier, which can not only drive the p-n semiconductor quenching effect to compete with the h-BN photoelectrode for the consumption of electron donors and exciting light but also trigger a mimetic enzymatic catalytic precipitation effect to inhibit electron transfer. The quenching ability and peroxidase-like activity of CuS QDs/CoO polyhedra were evaluated to prove its superiority, and the possible mechanisms of electron transfer and enzymatic catalytic were further analyzed in detail. The developed PEC biosensing platform for the chlorpyrifos assay presented outstanding performance with a wide linear range from 1 × 10 to 1 × 10 ng mL and a low detection limit of 0.34 pg mL and exhibited excellent selectivity, reproducibility, and stability. In addition, the CuS QDs/CoO polyhedra-activated h-BN PEC biosensing platform may exhibit universality for various analytes via replacing the corresponding target aptamer sequence. This work provides a remarkable inspiration and valuable reference for the development of the PEC biosensor, and the signal amplifier-enabled unmodified PEC biosensing platform strategy has a bright application in early safety warning, bioanalysis and clinical diagnosis.
在此，我们开发了一种未经修饰的六方氮化硼（h-BN）光电化学（PEC）生物传感平台，该平台具有低背景信号和高灵敏度，基于 CuS 量子点（QDs）/CoO 多面体驱动的多种信号放大。所制备的具有大比表面积的多孔 h-BN 纳米片作为光电基底材料，可以提供广泛的活性反应位点。同时，通过沸石咪唑酯骨架（ZIF-67）合成了 CuS QDs/CoO 多面体作为多重信号放大器，它不仅可以驱动 p-n 半导体猝灭效应与 h-BN 光电电极竞争电子供体和激发光的消耗，还可以触发模拟酶催化沉淀效应来抑制电子转移。评估了 CuS QDs/CoO 多面体的猝灭能力和过氧化物酶样活性，以证明其优越性，并进一步详细分析了电子转移和酶催化的可能机制。开发的用于测定毒死蜱的 PEC 生物传感平台具有出色的性能，线性范围从 1×10 到 1×10 ng mL，检测限低至 0.34 pg mL，并且表现出出色的选择性、重现性和稳定性。此外，CuS QDs/CoO 多面体激活的 h-BN PEC 生物传感平台可以通过替换相应的目标适体序列对各种分析物表现出通用性。这项工作为 PEC 生物传感器的发展提供了显著的启示和有价值的参考，并且启用信号放大器的未修饰 PEC 生物传感平台策略在早期安全预警、生物分析和临床诊断方面具有广阔的应用前景。
