title: Immunosensor based on carbon nanotube/manganese dioxide electrochemical tags.
abstract: This article reports on carbon nanotube/manganese dioxide (CNT-MnO2) composites as electrochemical tags for non-enzymatic signal amplification in immunosensing. The synthesized CNT-MnO2 composites showed good electrochemical activity, electrical conductivity and stability. The electrochemical signal of CNT-MnO2 composites coated glassy carbon electrode (GCE) increased by nearly two orders of magnitude compared to bare GCE in hydrogen peroxide (H2O2) environment. CNT-MnO2 composite was subsequently validated as electrochemical tags for sensitive detection of α-fetoprotein (AFP), a tumor marker for diagnosing hepatocellular carcinoma. The electrochemical immunosensor demonstrated a linear response on a log-scale for AFP concentrations ranging from 0.2 to 100 ng mL(-1). The limit of detection (LOD) was estimated to be 40 pg mL(-1) (S/N=3) in PBS buffer. Further measurements using AFP spiked plasma samples revealed the applicability of fabricated CNT-MnO2 composites for clinical and diagnostic applications.
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, 639798, Singapore; Center for Biomimetic Sensor Science, 50 Nanyang Drive, 637553, Singapore.
authors.forename: Meng-Che
authors.initials: MC
authors.lastname: Tu
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, 639798, Singapore; Tum Create, 1 Create Way #10-02 Create Tower, 138602, Singapore.
authors.forename: Han-Yi
authors.initials: HY
authors.lastname: Chen
authors.affiliation: Tum Create, 1 Create Way #10-02 Create Tower, 138602, Singapore.
authors.forename: Yuxi
authors.initials: Y
authors.lastname: Wang
authors.affiliation: DSO National Laboratories, 27 Medical Drive, 117510, Singapore.
authors.forename: Shabbir M
authors.initials: SM
authors.lastname: Moochhala
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, 639798, Singapore; Center for Biomimetic Sensor Science, 50 Nanyang Drive, 637553, Singapore.
authors.forename: Palaniappan
authors.initials: P
authors.lastname: Alagappan
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, 639798, Singapore; Center for Biomimetic Sensor Science, 50 Nanyang Drive, 637553, Singapore. Electronic address: bliedberg@ntu.edu.sg.
authors.forename: Bo
authors.initials: B
authors.lastname: Liedberg
mesh_terms: D000906:Antibodies / Q000276:immunology; D015374:Biosensing Techniques; D048271:Chitosan / Q000737:chemistry; D055664:Electrochemical Techniques; D004566:Electrodes; D006801:Humans; D006861:Hydrogen Peroxide / Q000737:chemistry; D017895:Manganese Compounds / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D000509:alpha-Fetoproteins / Q000032:analysis* / Q000276:immunology
chemical_list: D000906:Antibodies; D017895:Manganese Compounds; D037742:Nanotubes, Carbon; D010087:Oxides; D000509:alpha-Fetoproteins; D048271:Chitosan; D006861:Hydrogen Peroxide; C016552:manganese dioxide
keywords: Biosensors; CNT–MnO(2) composites; Electrochemical immunosensor; Electrochemical nanotags