Self-Supplied Electron Photoelectrochemical Biosensor with PTB7-Th as a Photoelectric Material and Biotin as an Efficient Quencher

• Published in: ACS applied materials & interfaces 2022-11, Vol.14 (47), p.53398-53404
• Main Authors: Li, Mengjie, An, Siyu, Wu, Ying, Yan, Zhitao, Chai, Yaqin, Yuan, Ruo
• Format: Article
• Language: English
• Subjects: Surfaces, Interfaces, and Applications
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.2c14921

In this work, a self-supplied electron photoelectrochemical (PEC) biosensor for sensitive determination of Pb2+ was established by utilizing donor–acceptor (D-A)-type PTB7-Th (poly­{4,8-bis­[5-(2-ethylhexyl) thiophen-2-yl]­benzo­[1,2-b,4,5-b′]­dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)­carbonyl] thieno­[3,4-b]-thiophene-4,6-diyl}) as a photoelectric material coupled with biotin as an efficient signal quencher. Impressively, compared with the traditional PEC signal quenchers, biotin was first applied as a PEC signal quencher in this work and it effectively avoided a cumbersome preparation process, complex DNA sequence design, and extra reagent assistance and greatly simplified experimental steps, which could achieve an efficient PEC signal quenching toward PTB7-Th. In addition, the execution of a DNAzyme-assisted Pb2+ recycling amplification reaction could release the quencher biotin, leading to the recovery of the PEC signal, thereby realizing the quantitative detection of Pb2+. Resultantly, the submitted self-supplied electron PEC biosensor presented an extensive coverage of assay Pb2+ (50 fM to 500 nM) along with a low determination limit (16.7 fM), which exhibited the advantages of high selectivity and excellent stability. Importantly, this work provided a powerful alternative to traditional heavy metal-ion assessment methods and possessed the potential for application in environment, biomedicine, and food-safety fields.