title: A novel immunosensing platform for highly sensitive prostate specific antigen detection based on dual-quenching of photocurrent from CdSe sensitized TiO2electrode by gold nanoparticles decorated polydopamine nanospheres.
abstract: Herein, a novel photoelectrochemical (PEC) immunosensing platform for highly sensitive detection of prostate specific antigen (PSA) was constructed based on dual-quenching of photocurrent from CdSe sensitized TiO2electrode by gold nanoparticles decorated dopamine-melanin nanospheres (AuNPs-Dpa-melanin CNSs). In this proposal, CdSe sensitized TiO2was used as photoelectrochemical matrix and the functional AuNPs-Dpa-melanin CNSs were used as signal quenching element. The dual quenching of the gold nanoparticles decorated Dpa-melanin CNSs to the CdSe sensitized TiO2was achieved as follows: (i) the strong energy transfer between the CdSe quantum dots (QDs) and Au NPs diminishes the photocurrent signal of CdSe QDs; (ii) the steric hindrance of AuNPs-Dpa-melanin CNSs partly obstructs the diffusion of the electron donor, i.e. ascorbic acid, to the surface of photoelectrode, which make the depleting efficiency of the photogenerated holes decrease, leading to a declined photocurrent intensity. On the basis of the dual quenching effect of AuNPs-Dpa-melanin CNSs, a competitive immunosensing platform for PSA was designed upon the specific binding of anti-PSA to PSA and PSA functionalized AuNPs-Dpa-melanin CNSs conjugates. This proposed immunosensor possesses wide linear range from 1.0×10-11gmL-1to 1.0×10-7gmL-1with the detection limit of 2.7pgmL-1. Moreover, the applicability of the present method was demonstrated in the determination of PSA in human serum. The strategy creates new paradigms for PSA and other tumor markers detection and demonstrates high sensitivity, good specificity, and satisfied applicability in complex biological samples.
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 46400, China; Institute for Conservation and Utilization of Agro-bioresources in Dabie Mountains, Xinyang Normal University, Xinyang 464000, China.
authors.forename: Yu-Xiang
authors.initials: YX
authors.lastname: Dong
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 46400, China; Institute for Conservation and Utilization of Agro-bioresources in Dabie Mountains, Xinyang Normal University, Xinyang 464000, China. Electronic address: jtcao11@163.com.
authors.forename: Jun-Tao
authors.initials: JT
authors.lastname: Cao
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 46400, China; Institute for Conservation and Utilization of Agro-bioresources in Dabie Mountains, Xinyang Normal University, Xinyang 464000, China. Electronic address: liuym9518@sina.com.
authors.forename: Yan-Ming
authors.initials: YM
authors.lastname: Liu
authors.affiliation: Xinyang Central Hospital, Xinyang 464000, China.
authors.forename: Shu-Hui
authors.initials: SH
authors.lastname: Ma
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D015374:Biosensing Techniques / Q000295:instrumentation; D019187:Cadmium Compounds / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004566:Electrodes; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation; D007211:Indoles / Q000737:chemistry*; D057230:Limit of Detection; D008543:Melanins / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D054118:Nanospheres / Q000737:chemistry / Q000648:ultrastructure; D055668:Photochemical Processes; D011108:Polymers / Q000737:chemistry*; D017430:Prostate-Specific Antigen / Q000097:blood*; D018036:Selenium Compounds / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D055910:Antibodies, Immobilized; D019187:Cadmium Compounds; D007211:Indoles; D008543:Melanins; D011108:Polymers; D018036:Selenium Compounds; C081789:dopamine melanin; C568283:polydopamine; C009495:titanium dioxide; D006046:Gold; C058667:cadmium selenide; D014025:Titanium; D017430:Prostate-Specific Antigen
keywords: AuNPs-Dpa-melanin CNSs; Dual quenching strategy; Exciton energy transfer; Photoelectrochemical biosensor; Prostate specific antigen; Steric hindrance effect