title: Magnetic beads-based electrochemiluminescence immunosensor for determination of cancer markers using quantum dot functionalized PtRu alloys as labels.
abstract: A novel electrochemiluminescence (ECL) immunosensor for sensitive detection of human chorionic gonadotrophin antigen (HCG-Ag) was constructed using CdTe quantum dot functionalized nanoporous PtRu alloys (QDs@PtRu) as labels for signal amplification. In this paper, nanoporous PtRu alloy was employed as the carrier for immobilization of CdTe QDs and antibodies. Primary monoclonal antibody to alfa-HCG antigen (McAb(1)) was immobilized onto the surface of chitosan coated Fe(3)O(4) magnetic nanoparticles (Fe(3)O(4)/CS MNPs) by glutaraldehyde (GA) as coupling agent. Then McAb(1) could be easily separated and assembled on the surface of indium tin oxide glass (ITO) owing to their excellent magnetic properties with external magnetic forces holding the MNPs. Due to signal amplification from the high loading of CdTe QDs, 4.67-fold enhancements in ECL signal for HCG-Ag detection was achieved compared to the unamplified method (single QDs as labels). Under optimal conditions, a wide detection range (0.005~50 ng mL(-1)) and low detection limit (0.8 pg mL(-1)) were achieved through the sandwich-type immunosensor. The novel immunosensor showed high sensitivity and selectivity, excellent stability, and good reproducibility, and thus has great potential for clinical detection of HCG-Ag. In particular, this approach presents a novel class of combining bifunctional nanomaterials with preferable ECL properties and excellent magnetism, which suggests considerable potential in a wide range of applications for bioassays.
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Shenguang
authors.initials: S
authors.lastname: Ge
authors.forename: Shaowei
authors.initials: S
authors.lastname: Wang
authors.forename: Mei
authors.initials: M
authors.lastname: Yan
authors.forename: Jinghua
authors.initials: J
authors.lastname: Yu
authors.forename: Xianrang
authors.initials: X
authors.lastname: Song
authors.forename: Weiyan
authors.initials: W
authors.lastname: Liu
mesh_terms: D000497:Alloys / Q000737:chemistry*; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000097:blood; D015374:Biosensing Techniques / Q000379:methods*; D019187:Cadmium Compounds / Q000737:chemistry; D048271:Chitosan / Q000737:chemistry; D004563:Electrochemistry; D052203:Ferrosoferric Oxide / Q000737:chemistry; D017022:Flow Injection Analysis; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008163:Luminescent Measurements; D059346:Magnets / Q000737:chemistry*; D008863:Microspheres; D058608:Nanopores; D010984:Platinum / Q000737:chemistry; D045663:Quantum Dots; D012428:Ruthenium / Q000737:chemistry; D013691:Tellurium / Q000737:chemistry
chemical_list: D000497:Alloys; D014408:Biomarkers, Tumor; D019187:Cadmium Compounds; D010984:Platinum; D012428:Ruthenium; D048271:Chitosan; D013691:Tellurium; C028337:cadmium telluride; D052203:Ferrosoferric Oxide