title: Ultrasensitive electrochemical immunosensor based on Au nanoparticles dotted carbon nanotube-graphene composite and functionalized mesoporous materials.
abstract: A facile and sensitive electrochemical immunosensor for detection of human chorionic gonadotrophin (hCG) was designed by using functionalized mesoporous nanoparticles as bionanolabels. To construct high-performance electrochemical immunosensor, Au nanoparticles (AuNPs) dotted carbon nanotubes (MWCNTs)-graphene composite was immobilized on the working electrode, which can increase the surface area to capture a large amount of primary antibodies (Ab(1)) as well as improve the electronic transmission rate. The as-prepared bionanolabels. composed of mesoporous silica nanoparticles (MCM-41) coated with AuNPs through thionine linking, showed good adsorption of horseradish peroxidase-labeled secondary anti-hCG antibody. Interlayer thionine was not only a bridging agent between MCM-41 and AuNPs but also an excellent electron mediator. The approach provided a good linear response range from 0.005 to 500 mIU mL(-1) with a low detection limit of 0.0026 mIU mL(-1). The immunosensor showed good precision, acceptable stability and reproducibility. Satisfactory results were obtained for determination of hCG in human serum samples. The proposed method provides a new promising platform of clinical immunoassay for other biomolecules.
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: Juanjuan
authors.initials: J
authors.lastname: Lu
authors.forename: Shiquan
authors.initials: S
authors.lastname: Liu
authors.forename: Shenguang
authors.initials: S
authors.lastname: Ge
authors.forename: Mei
authors.initials: M
authors.lastname: Yan
authors.forename: Jinghua
authors.initials: J
authors.lastname: Yu
authors.forename: Xiutao
authors.initials: X
authors.lastname: Hu
mesh_terms: D015374:Biosensing Techniques; D006063:Chorionic Gonadotropin / Q000097:blood*; D055664:Electrochemical Techniques; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry; D016062:Porosity; D012680:Sensitivity and Specificity
chemical_list: D006063:Chorionic Gonadotropin; D037742:Nanotubes, Carbon; D006046:Gold; D006108:Graphite