title: An ultrasensitive sandwich-type electrochemical immunosensor based on the signal amplification strategy of mesoporous core-shell Pd@Pt nanoparticles/amino group functionalized graphene nanocomposite.
abstract: Herein, a novel and sensitive sandwich-type electrochemical immunosensor was fabricated for quantitative monitoring of prostate specific antigen (PSA). The sulfo group functionalized multi-walled carbon nanotubes (MWCNTs-SO3H) were used as substrate material to increase the specific surface area and enhance the conductivity of the glassy carbon electrode. Gold nanoparticles (Au NPs) were introduced to enhance the load capacity of the substrate material for primary antibodies (Ab1) and accelerate the electron transfer on the electrode interface. The mesoporous core-shell Pd@Pt nanoparticle loaded by amino group functionalized graphene (M-Pd@Pt/NH2-GS) with high specific surface area, high indexed facets, and good biocompatibility was not only as the carriers of secondary antibodies (Ab2) but also catalyzed the reduction of hydrogen peroxide (H2O2), which effectually amplified the current signal in detection of PSA. The as-proposed immunosensor exhibited high sensitivity and stability on the detection of PSA. A linear relationship between current signals and the concentrations of PSA was obtained in the range from 10fg/mL to 50ng/mL and the detection limit of PSA was 3.3fg/mL (signal-to-noise ratio of 3). Furthermore, the as-proposed immunosensor showed excellent performance in detection of human serum samples. The results suggest that the proposed immunosensor will be promising in the diagnostics application for accurately quantitative detection of PSA.
authors.affiliation: School of Chemical Engineering, Shandong University of Technology, 255049 Zibo, PR China.
authors.forename: Mingdang
authors.initials: M
authors.lastname: Li
authors.affiliation: School of Chemical Engineering, Shandong University of Technology, 255049 Zibo, PR China. Electronic address: wangping876@163.com.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: School of Chemical Engineering, Shandong University of Technology, 255049 Zibo, PR China.
authors.forename: Faying
authors.initials: F
authors.lastname: Li
authors.affiliation: School of Chemical Engineering, Shandong University of Technology, 255049 Zibo, PR China.
authors.forename: Qingyan
authors.initials: Q
authors.lastname: Chu
authors.affiliation: School of Chemical Engineering, Shandong University of Technology, 255049 Zibo, PR China.
authors.forename: Yueyun
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Chemical Engineering, Shandong University of Technology, 255049 Zibo, PR China.
authors.forename: Yunhui
authors.initials: Y
authors.lastname: Dong
mesh_terms: D000588:Amines / Q000737:chemistry; D055910:Antibodies, Immobilized / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods; D055664:Electrochemical Techniques / Q000379:methods*; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; 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; D037742:Nanotubes, Carbon / Q000737:chemistry / Q000648:ultrastructure; D010165:Palladium / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*; D016062:Porosity; D017430:Prostate-Specific Antigen / Q000097:blood*; D059629:Signal-To-Noise Ratio
chemical_list: D000588:Amines; D055910:Antibodies, Immobilized; D037742:Nanotubes, Carbon; D010984:Platinum; D010165:Palladium; D006046:Gold; D006108:Graphite; D017430:Prostate-Specific Antigen
keywords: Gold nanoparticles; Mesoporous core-shell Pd@Pt nanoparticles; Prostate specific antigen; Sandwich-type immunosensor; Sulfonated multi-walled carbon nanotubes