title: Nanostructured screen-printed electrodes based on titanate nanowires for biosensing applications.
abstract: This work demonstrates the successful modification of screen-printed electrodes using functionalized titanate nanowires for producing a peroxide biosensor. Titanate nanowires were synthesized by the hydrothermal method and characterized using physico-chemical techniques. The surface of the nanowires was modified with (3-aminopropyl)trimethoxysilane and glutaraldehyde to immobilize horseradish peroxidase through covalent bound, obtaining a surface coverage of 1.62mg of enzyme/m2. The surface of screen-printed carbon electrodes was modified with peroxidase-containing nanowires. Cyclic voltammetry and chronoamperometry were employed to study the electrochemical properties of the nanostructured electrode. A low hydrogen peroxide reduction potential around -0.98V (vs Ag, pH7.0) was observed, with linear response in the range of 40 to 560μmolL-1, detection limit of 10.7μmolL-1and good stability. Reproducibility relative standard deviation was as low as 4.7%. For repeatability, deviation was 3.3%.
authors: Programa de Engenharia Química, COPPE - Universidade Federal do Rio de Janeiro, P.O. Box 68502, Rio de Janeiro, RJ 21941-914, Brazil. Electronic address: helen@peq.coppe.ufrj.br.
authors: Helen Conceição
authors: HC
authors: Ferraz
authors: Programa de Engenharia Química, COPPE - Universidade Federal do Rio de Janeiro, P.O. Box 68502, Rio de Janeiro, RJ 21941-914, Brazil.
authors: Daniela Ferreira
authors: DF
authors: Machado
authors: Programa de Engenharia Química, COPPE - Universidade Federal do Rio de Janeiro, P.O. Box 68502, Rio de Janeiro, RJ 21941-914, Brazil.
authors: Neuman Solange
authors: NS
authors: de Resende
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004563:Electrochemistry; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000378:metabolism; D006735:Horseradish Peroxidase / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000032:analysis; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure; D011327:Printing; D015203:Reproducibility of Results; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D004800:Enzymes, Immobilized; D006861:Hydrogen Peroxide; D014025:Titanium; D006735:Horseradish Peroxidase
keywords: Biosensor; Enzyme immobilization; Horseradish peroxidase; Hydrogen peroxide; Screen-printed electrode; Titanate nanowires