Single-Atom-Based Heterojunction Coupling with Ion-Exchange Reaction for Sensitive Photoelectrochemical Immunoassay.


Qin Y(1), Wen J(2), Zheng L(3), Yan H(1), Jiao L(1), Wang X(1), Cai X(1), Wu Y(1), Chen G(1), Chen L(4), Hu L(2), Gu W(1), Zhu C(1).
Author information:
(1)Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University, Wuhan 430079, P.R. China.
(2)Hubei Engineering Technology Research Center of Optoelectronic and New Energy Materials, Hubei Key Laboratory of Plasma Chemistry and Advanced Materials, School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan 430205, P.R. China.
(3)Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P. R. China.
(4)Department of Medical Imaging, Henan Provincial People's Hospital & the People's Hospital of Zhengzhou University, Zhengzhou 450003, P. R. China.


Benefiting from the maximum atom-utilization efficiency and distinct structural features, single-atom catalysts open a new avenue for the design of more functional catalysts, whereas their bioapplications are still in their infancy. Due to the advantages, platinum single atoms supported by cadmium sulfide nanorods (Pt SAs-CdS) are synthesized to build an ultrasensitive photoelectrochemical (PEC) biosensing platform. With the decoration of Pt SAs, the PEC signal of CdS is significantly boosted. Furthermore, theory calculations indicate the positively charged Pt SAs could change the charge distribution and increase the excited carrier density of CdS. Meanwhile, it also suggests that Cu2+ can severely hinder the photoexcitation and electron-hole separation of CdS. As a proof of concept, prostate-specific antigen is chosen as the target analyte to demonstrate the superiority of the Pt SAs-CdS-based PEC sensing system. As a result, the PEC biosensor based on Pt SAs-CdS exhibits outstanding detection sensitivity and promising applicability.