title: Ultrasensitive sandwich-type electrochemical immunosensor based on trimetallic nanocomposite signal amplification strategy for the ultrasensitive detection of CEA.
abstract: A novel and ultrasensitive sandwich-type electrochemical immunosensor was designed for the quantitative detection of carcino-embryonic antigen (CEA). This immunosensor was developed by using the trimetallic NiAuPt nanoparticles on graphene nanosheets (NGs) nanosheets (NiAuPt-NGs) as excellent labels and β-cyclodextrin functionalized reduced graphene oxide nanosheets (CD-NGs) as the platform. The CD-NGs with high specific surface area good biocompatibility and the ideal dispersibility was used to capture the primary antibodies (Ab1) efficiently. The trimetallic NiAuPt-NGs nanocomposites were used as the labels for signal amplification, showing better electrocatalytic activity towards the reduction of hydrogen peroxide (H2O2), which is much better than that the monometallic Pt-NGs, bimetallic NiPt-NGs and AuPt-NGs due to the synergetic effect presented in NiAuPt-NGs. The NiAuPt-NGs nanocomposites consist of tightly coupled nanostructures of Au, Ni and Pt, which have neither an alloy nor a core-shell structure. Under the optimal conditions, a linear range from 0.001-100 ng/mL and a low detection limit of 0.27 pg/mL were obtained for CEA. The proposed electrochemical sandwich-type immunosensor may have a promising application in bioassay and it enriches the electrochemical immunoassays.
authors.affiliation: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.
authors.forename: Lihui
authors.initials: L
authors.lastname: Tian
authors.affiliation: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.affiliation: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.
authors.forename: Yueyuan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wei
authors.affiliation: Key Laboratory of Chemical Sensing &Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cao
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D014408:Biomarkers, Tumor / Q000032:analysis*; D015374:Biosensing Techniques; D002272:Carcinoembryonic Antigen / Q000032:analysis* / Q000097:blood; D003110:Colonic Neoplasms / Q000175:diagnosis*; D055664:Electrochemical Techniques / Q000379:methods*; D006108:Graphite / Q000737:chemistry; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry; D010084:Oxidation-Reduction; D010984:Platinum / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D047392:beta-Cyclodextrins / Q000737:chemistry
chemical_list: D055910:Antibodies, Immobilized; D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D047392:beta-Cyclodextrins; D012834:Silver; D010984:Platinum; D006108:Graphite; D009532:Nickel; D006861:Hydrogen Peroxide; C031215:betadex