title: A novel approach for the fabrication of a flexible glucose biosensor: The combination of vertically aligned CNTs and a conjugated polymer.
abstract: A novel flexible glucose biosensor using vertically aligned carbon nanotubes (VACNT) and a conjugated polymer (CP) was fabricated. A scaffold based on VACNT grown on aluminum foil (VACNT-Al foil) with poly (9,9-di-(2-ethylhexyl)-fluorenyl-2,7-diyl)-end capped with 2,5-diphenyl-1,2,4-oxadiazole (PFLO) was used as the immobilization matrix for the glucose biosensor. Glucose oxidase (GOx) was immobilized on a modified indium tin oxide (ITO) coated polyethylene terephthalate (PET) electrode surface. The biosensor response at a potential of -0.7V versus Ag wire was followed by the decrease in oxygen level as a result of enzymatic reaction. The biosensor exhibited a linear range between 0.02mM and 0.5mM glucose and kinetic parameters (KMapp, Imax, limit of detection (LOD) and sensitivity) were estimated as 0.193mM, 8.170μA, 7.035×10-3mM and 65.816μA/mMcm2, respectively. Scanning electron microscopy (SEM) was used for surface characterization. The constructed biosensor was applied to determine the glucose content in several beverages.
authors.affiliation: Department of Chemistry, Middle East Technical University, Ankara 06800, Turkey. Electronic address: tugba.ceren@windowslive.com.
authors.forename: Tugba Ceren
authors.initials: TC
authors.lastname: Gokoglan
authors.affiliation: Department of Chemistry, Middle East Technical University, Ankara 06800, Turkey. Electronic address: saniyesoylemez@gmail.com.
authors.forename: Saniye
authors.initials: S
authors.lastname: Soylemez
authors.affiliation: Department of Chemistry, Middle East Technical University, Ankara 06800, Turkey. Electronic address: kesik.melis@gmail.com.
authors.forename: Melis
authors.initials: M
authors.lastname: Kesik
authors.affiliation: Micro and Nanotechnology, Middle East Technical University, Ankara 06800, Turkey. Electronic address: e165033@metu.edu.tr.
authors.forename: Itir Bakis
authors.initials: IB
authors.lastname: Dogru
authors.affiliation: Department of Metallurgical and Material Engineering, Middle East Technical University, Ankara 06800, Turkey. Electronic address: e174543@metu.edu.tr.
authors.forename: Onur
authors.initials: O
authors.lastname: Turel
authors.affiliation: Micro and Nanotechnology, Middle East Technical University, Ankara 06800, Turkey. Electronic address: reyuksel@metu.edu.tr.
authors.forename: Recep
authors.initials: R
authors.lastname: Yuksel
authors.affiliation: Micro and Nanotechnology, Middle East Technical University, Ankara 06800, Turkey; Department of Metallurgical and Material Engineering, Middle East Technical University, Ankara 06800, Turkey. Electronic address: unalan@metu.edu.tr.
authors.forename: Husnu Emrah
authors.initials: HE
authors.lastname: Unalan
authors.affiliation: Department of Chemistry, Middle East Technical University, Ankara 06800, Turkey; Department of Biotechnology, Middle East Technical University, Ankara 06800, Turkey; Department of Polymer Science and Technology, Middle East Technical University, Ankara 06800, Turkey; The Center for Solar Energy Research and Application (GUNAM), Middle East Technical University, Ankara 06800, Turkey. Electronic address: toppare@metu.edu.tr.
authors.forename: Levent
authors.initials: L
authors.lastname: Toppare
mesh_terms: D001628:Beverages / Q000032:analysis; D015374:Biosensing Techniques / Q000379:methods*; D004800:Enzymes, Immobilized; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D011108:Polymers; D005949:Glucose Oxidase; D005947:Glucose
keywords: Amperometric biosensor; Conjugated polymer; Enzyme electrode; Glucose biosensor; Glucose oxidase; Vertically aligned carbon nanotubes