title: An ultrasensitive electrochemical immunosensor for the detection of prostate-specific antigen based on conductivity nanocomposite with halloysite nanotubes.
abstract: 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 H2O2and 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. Graphical Abstract A new label-free amperometric electrochemical immunosensor based on HNTs@PPy-Pd nanocomposite for quantitative detection of PSA.
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, Shandong, 250022, China.
authors.forename: Yueyuan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, Shandong, 250022, China.
authors.forename: Malik Saddam
authors.initials: MS
authors.lastname: Khan
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, Shandong, 250022, China.
authors.forename: Lihui
authors.initials: L
authors.lastname: Tian
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, Shandong, 250022, China.
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, Shandong, 250022, China.
authors.forename: Lihua
authors.initials: L
authors.lastname: Hu
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, Shandong, 250022, China.
authors.forename: Dawei
authors.initials: D
authors.lastname: Fan
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, Shandong, 250022, China. sdjndxcw@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Cao
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan, Shandong, 250022, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wei
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D055910:Antibodies, Immobilized / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D000077215:Clay; D055664:Electrochemical Techniques / Q000379:methods; D006801:Humans; D007118:Immunoassay / Q000379:methods; D057230:Limit of Detection; D008297:Male; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D053761:Nanocomposites / Q000737:chemistry / Q000648:ultrastructure; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D010165:Palladium / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D017430:Prostate-Specific Antigen / Q000097:blood*; D011758:Pyrroles / Q000737:chemistry*
chemical_list: D000538:Aluminum Silicates; D055910:Antibodies, Immobilized; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D010165:Palladium; D017430:Prostate-Specific Antigen; D000077215:Clay
keywords: Halloysite nanotubes; Label-free immunosensor; Polypyrrole shell; Prostate-specific antigen