title: Magnetic graphene nanosheets based electrochemiluminescence immunoassay of cancer biomarker using CdTe quantum dots coated silica nanospheres as labels.
abstract: A highly sensitive electrochemiluminescence (ECL) immunosensor for the detection of prostate specific antigen (PSA) was designed using biofunctionalized magnetic graphene nanosheets (G@Fe(3)O(4)) as immunosensing probes and CdTe quantum dots coated silica nanospheres (Si/QDs) as signal amplification labels. In this work, a sandwich-type immunosensor was fabricated, which was assembled on the surface of indium tin oxide glass (ITO). The analyte was detected in a home-made flow injection ECL (FI-ECL) cell through the immunosensor. Owing to the signal amplification of G@Fe(3)O(4) composite and Si/QDs, the ECL measurement showed a great increase in detection signals compared with the unampliﬁed method. Under optimal conditions, a wide detection range (0.003-50 ng mL(-1)) and a low detection limit (0.72 pg mL(-1)) were obtained through the sandwich-type immunosensor. The proposed strategy successfully demonstrated a reproducible, speciﬁc, and potent method that can be expanded to detect other proteins.
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 250022, PR China.
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Shenguang
authors.initials: S
authors.lastname: Ge
authors.forename: Juanjuan
authors.initials: J
authors.lastname: Lu
authors.forename: Jinghua
authors.initials: J
authors.lastname: Yu
authors.forename: Xianrang
authors.initials: X
authors.lastname: Song
authors.forename: Su
authors.initials: S
authors.lastname: Liu
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis* / Q000097:blood; D019187:Cadmium Compounds / Q000737:chemistry*; D004563:Electrochemistry; D004579:Electron Transport; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008163:Luminescent Measurements; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D017430:Prostate-Specific Antigen / Q000032:analysis / Q000097:blood; D045663:Quantum Dots; D012822:Silicon Dioxide / Q000737:chemistry*; D013194:Staining and Labeling; D013691:Tellurium / Q000737:chemistry*
chemical_list: D014408:Biomarkers, Tumor; D019187:Cadmium Compounds; D058185:Magnetite Nanoparticles; D012822:Silicon Dioxide; D006108:Graphite; D017430:Prostate-Specific Antigen; D013691:Tellurium; C028337:cadmium telluride