Novel Anti-Interference Strategy for a Self-Powered Sensor: Mediator-Free and Biospecific Photocathode Interface

Abstract

As a new electrochemical sensing concept, a self-powered sensor shows a good application prospect in the field of analysis. However, it is still a great challenge to improve the anti-interference capability of sensors through reasonable design. In this study, we investigated the difference between the single photoanode and photocathode self-powered sensor and combined the advantages of these two aspects to fabricate a mediator-free self-powered aptasensor based on the dual-photoelectrode system, which combined the biological events from the photocathode. The biological events occurred at the photocathode could avoid the interference caused by the generated hole oxidation of reducing small molecules in the real sample on the photoanode surface, which was helpful to enhance the anti-interference capability of the sensor. Moreover, due to the sufficient Fermi level differentiation between two photoelectrodes, the redox mediator was not necessary. This could avoid the redox reaction caused by the introduction of extra electron donors or electron acceptors occurring before the photoelectrical behavior, thus improving the accuracy of the sensor. According to the influence of the generated biological conjugate on the external circuit, electron transmission between interfaces, and the obstruction of visible light irradiation, the sensitive and accurate detection of the analytical model was achieved. This work provided a proof-of-concept for the establishment of a mediator-free dual-photoelectrode self-powered sensing platform with high sensitivity and strong anti-interference performance.

Photoelectrochemical sandwich immunoassay of CYFRA21-1 based on In2O3/WO3type-II heterojunction and CdS quantum dots-polydopamine nanospheres labeling

“…† 44 In M-S plots, an n-type semiconductor gives a positive slope of the ramp, a p-type semiconductor gives a negative slope of the ramp, and the flatband potential (E fb ) of the n-type or p-type semiconductor can be obtained by intersecting the ramp-extension line of the M-S plot with the abscissa. 45,46 As shown in Fig. S4D-F, † we can conclude that In 2 O 3 , WO 3 and CdS QDs are all n-type semiconductors, and their E fb values are −0.42 V (vs. NHE), 0.85 V (vs. NHE) and −0.50 V (vs. NHE), respectively.…”

Turning on High‐Sensitive Organic Electrochemical Transistor‐Based Photoelectrochemical‐Type Sensor over Modulation of Fe‐MOF by PEDOT

“…The as‐constructed OECT‐PEC sensor inherits the advantages of the separate forms of signal from the excitation source (light illumination) and signal detection system (electric output) of the PEC sensor, resulting in a lower background signal and voltage‐free working electrode that effectively reduces possible interferences from electroactive substances. [ 9 ] Furthermore, it would also incorporate the advantages of the OECT, including excellent signal amplification and ease of miniaturization. [ 10 ] To date, only a few studies have reported the combination of a PEC and OECT.…”

Zinc–Air Battery-Assisted Self-Powered PEC Sensors for Sensitive Assay of PTP1B Activity Based on Perovskite Quantum Dots Encapsulated in Vinyl-Functionalized Covalent Organic Frameworks

“…A self-powered biosensing platform is an important implementation form for POCT due to its no additional power supply and easy miniaturization and has broad applications in clinical diagnosis, food analysis, environmental detection, and so forth. − As one kind of self-powered biosensing platforms, several self-powered PEC sensors have been developed recently. For example, Yan et al reported a self-powered PEC aptasensor of PCB77 assay based on visible light-driven membraneless photocatalytic fuel cells .…”