title: Electrochemical immunoassay for carcinoembryonic antigen based on signal ampliﬁcation strategy of nanotubular mesoporous PdCu alloy.
abstract: Interests in using nanoporous metals for biosensing applications have been increasing. Herein, nanotubular mesoporous PdCu (NM-PdCu) alloy is used to fabricate a novel label-free electrochemical immunosensor for cancer biomarker carcinoembryonic antigen (CEA). It operates through physisorption of anti-CEA on NM-PdCu and the mixture of sulfonated graphene sheets (HSO(3)-GS) and thionine (TH) functionalized glassy carbon electrode interface as the detection platform. In this study, chitosan (CS)-PdCu is bound very strongly to carcinoembryonic antibody (anti-CEA), because of the good electron conductivity, high surface area, and good biocompatibility. CS-PdCu is immobilized on electrodes by electrostatic interactions between the negatively charged sulfo group of HSO(3)-GS and the abundant positively charged amino groups of chitosan. TH acts as the redox probe. Under the optimized conditions, the electrochemical immunosensor exhibits a wide working range from 0.01 to 12 ng/mL with a low detection limit of 4.86 pg/mL. The accuracy, reproducibility, and stability of the immunosensor are acceptable. The assay is evaluated for real serum samples, receiving satisfactory results. The nanoporous metal materials-based immunoassay provides a promising approach in clinical application and thus represents a versatile detection method.
authors.affiliation: Key Laboratory of Chemical Sensing and Analysis in Universities of Shandong (University of Jinan), School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Cai
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.forename: Yuyang
authors.initials: Y
authors.lastname: Li
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Hongmin
authors.initials: H
authors.lastname: Ma
authors.forename: Baocun
authors.initials: B
authors.lastname: Zhu
authors.forename: Caixia
authors.initials: C
authors.lastname: Xu
authors.forename: Qin
authors.initials: Q
authors.lastname: Wei
authors.forename: Dan
authors.initials: D
authors.lastname: Wu
authors.forename: Bin
authors.initials: B
authors.lastname: Du
mesh_terms: D000497:Alloys / Q000737:chemistry; D014408:Biomarkers, Tumor / Q000302:isolation & purification; D015374:Biosensing Techniques; D002272:Carcinoembryonic Antigen / Q000302:isolation & purification; D048271:Chitosan / Q000737:chemistry; D003300:Copper / Q000737:chemistry; D055664:Electrochemical Techniques / Q000379:methods; D006108:Graphite / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods; D057230:Limit of Detection; D058608:Nanopores; D010165:Palladium / Q000737:chemistry; D010640:Phenothiazines / Q000737:chemistry
chemical_list: D000497:Alloys; D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D010640:Phenothiazines; D010165:Palladium; D006108:Graphite; D003300:Copper; D048271:Chitosan; C009469:thionine