title: Sensitive immunosensor for tumor necrosis factor α based on dual signal amplification of ferrocene modified self-assembled peptide nanowire and glucose oxidase functionalized gold nanorod.
abstract: Sensitive electrochemical immunosensor for the detection of protein biomarker tumor necrosis factor α (TNF-α) was reported that uses ferrocene carboxylic acid (Fc) functionalized self-assembled peptide nanowire (Fc-PNW) as sensor platform and glucose oxidase (GOx) modified gold nanorod (GNR) as label. Greatly enhanced sensitivity is achieved based on a dual signal amplification strategy: first, the synthesized Fc-PNW used as the sensor platform increased the loading of primary anti-TNF-α antibody (Ab(1)) onto electrode surface due to its large surface area. At the same time, the Fc moiety on the nanowire is used as a mediator for GOx to catalyze the glucose reaction. Second, multiple GOx and secondary anti-TNF-α antibody (Ab(2)) molecules are bounded onto each GNR to increase the sensitivity of the immunosensor. After the preparation of the immunosensor based on the traditional sandwich protocol, the response of the immunosensor towards glucose was used as a signal to differentiate various concentrations of TNF-α. The resulting immunosensor has high sensitivity, wide linear range (0.005-10ng/mL) and good selectivity. This immunosensor preparation strategy is a promising platform for clinical screening of protein biomarkers.
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Sun
authors.forename: Liu
authors.initials: L
authors.lastname: Deng
authors.forename: Hao
authors.initials: H
authors.lastname: Gan
authors.forename: Rujuan
authors.initials: R
authors.lastname: Shen
authors.forename: Minghui
authors.initials: M
authors.lastname: Yang
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000276:immunology; D004800:Enzymes, Immobilized / Q000378:metabolism; D005296:Ferrous Compounds / Q000737:chemistry*; D005949:Glucose Oxidase / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D000075163:Metallocenes; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure; D010455:Peptides / Q000737:chemistry*; D012680:Sensitivity and Specificity; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis*
chemical_list: D055910:Antibodies, Immobilized; D000911:Antibodies, Monoclonal; D004800:Enzymes, Immobilized; D005296:Ferrous Compounds; D000075163:Metallocenes; D010455:Peptides; D014409:Tumor Necrosis Factor-alpha; D006046:Gold; D005949:Glucose Oxidase; C004998:ferrocene