Cu2+-Modulated in situ growth of quantum dots for split-type photoelectrochemical immunoassay of prostate-specific antigen.
Yang ZangYun JuJingjing JiangQin XuMing ChuHuaiguo XuePublished in: The Analyst (2019)
A split-type photoelectrochemical immunosensor was designed for the ultrasensitive monitoring of prostate-specific antigen (PSA) based on a Cu2+-mediated catalytic reaction for inhibiting the in situ generation of CdS quantum dots (QDs) coupled with the enhancement of the CdS/MoS2 heterojunction; it was constructed by the stepwise modification of MoS2 QDs and CdS QDs onto an ITO electrode surface. In the presence of PSA, CuO NP-labeled anti-PSA antibodies were immobilized onto an anti-PSA antibody-modified 96-well plate via a sandwich immunoreaction and dissolution by hydrochloric acid to obtain a large number of Cu2+ ions. As the Cu2+-triggered catalytic oxidization of glutathione occurred, the in situ growth of CdS QDs as a signal indicator was significantly suppressed, resulting in reduction in the photocurrent response. Under optimal conditions, the biosensor exhibited desirable linearity in the range from 0.5 pg mL-1 to 10 ng mL-1, low detection limit of 0.29 pg mL-1, satisfactory selectivity, and good stability. It was applied to PSA detection in human serum, suggesting a great potential for early diagnostics of some cancers.
Keyphrases
- quantum dots
- prostate cancer
- sensitive detection
- loop mediated isothermal amplification
- radical prostatectomy
- label free
- aqueous solution
- metal organic framework
- energy transfer
- wastewater treatment
- signaling pathway
- real time pcr
- computed tomography
- risk assessment
- pet imaging
- young adults
- high resolution
- room temperature
- human health
- carbon nanotubes
- solar cells
- water soluble
- reduced graphene oxide