An ultrasensitive electrochemical immunosensor for the detection of prostate-specific antigen based on conductivity nanocomposite with halloysite nanotubes
- 395 Downloads
A sensitive label-free amperometric electrochemical immunosensor for detection of prostate-specific antigen (PSA) was proposed in this work. The nanocomposite of halloysite nanotubes with polypyrrole shell and palladium nanoparticles (HNTs@PPy-Pd) was used as a novel signal label. The HNTs with adequate hydroxyl groups are economically available raw materials. PPy, as an electrically conducting polymer material, can be absorbed to the surface of HNTs by in situ oxidative polymerization of the pyrrole monomer and form a shell on the HNTs. The shell of PPy could not only improve the conductivity of the nanocomposite but also absorb large amounts of Pd nanoparticles (NPs). The Pd NPs with high electrocatalytic activity toward the reduction of H2O2 and the HNTs@PPy-Pd nanocomposite as the analytical signal label could improve the sensitivity of the immunosensor. Under optimal conditions, the immunosensor showed a low detection limit (0.03 pg/mL) and a wide linear range (0.0001 to 25 ng/mL) of PSA. Moreover, its merits such as good selectivity, acceptable reproducibility, and stability indicate that the fabricated immunosensor has a promising application potential in clinical diagnosis.
KeywordsHalloysite nanotubes Prostate-specific antigen Polypyrrole shell Label-free immunosensor
This study was supported by the Natural Science Foundation of Shandong Province (no. ZR2016BM20) and the National Natural Science Foundation of China (nos. 21377046, 21575050).
Compliance with ethical standards
Conflict of interest
For each author of this study, there is no conflict of interest and no direct or potential influence on or impart bias into the work (including financial and other relationships).
- 20.Sun T, Zhang Z, Xiao J, Chen C, Xiao F, Wang S, et al. Facile and green synthesis of palladium nanoparticles-graphene-carbon nanotube material with high catalytic activity. Sci Rep. 2013;3(8):2527.Google Scholar