title: Ultrasensitive electrochemiluminescence immunosensor using PtAg@carbon nanocrystals composites as labels and carbon nanotubes-chitosan/gold nanoparticles as enhancer.
abstract: An ultrasensitive electrochemiluminescence (ECL) immunosensor was developed using PtAg@carbon nanocrystals (CNCs) as excellent labels based on carbon nanotubes-chitosan/AuNPs (CNT-CHIT/AuNPs) composite modified screen-printed carbon electrodes (SPCEs) for prostate protein antigen (PSA) detection. The CNCs were obtained simply by electro-oxidation of graphite with abundant carboxyl groups at their surfaces. The PtAg bimetallic nanocomposites with hierarchically hollow structures were fabricated through simple replacement reaction using dealloyed nanoporous silver (NPS) as both a template and reducing agent. Structure characterization was obtained by means of transmission electron microscope (TEM) and scanning electron microscope (SEM) images. The PtAg@CNCs composites exhibit a 6 times higher ECL intensity than the pure CNCs labeled anti-PSA. The as-prepared CNT-CHIT/AuNPs composite can attach more antibody than pure CNTs. Due to the dual-amplification techniques, the concentrations of PSA were obtained in the range from 1 pg mL(-1) to 50 ng mL(-1) with a detection limit of 0.6 pg mL(-1). Finally, the as-proposed ECL immunosensor has the advantages of high sensitivity, specificity and stability and could become a promising technique for tumor marker detection.
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhang
authors.forename: Weijian
authors.initials: W
authors.lastname: Dai
authors.forename: Mei
authors.initials: M
authors.lastname: Yan
authors.forename: Shenguang
authors.initials: S
authors.lastname: Ge
authors.forename: Jinghua
authors.initials: J
authors.lastname: Yu
authors.forename: Xianrang
authors.initials: X
authors.lastname: Song
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
mesh_terms: D000497:Alloys / Q000737:chemistry; D048271:Chitosan / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008163:Luminescent Measurements / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry; D010984:Platinum / Q000737:chemistry*; D017430:Prostate-Specific Antigen / Q000032:analysis / Q000097:blood; D015203:Reproducibility of Results; D012834:Silver / Q000737:chemistry*
chemical_list: D000497:Alloys; D037742:Nanotubes, Carbon; D012834:Silver; D010984:Platinum; D048271:Chitosan; D017430:Prostate-Specific Antigen