title: Fabrication of gallium hexacyanoferrate modified carbon ionic liquid paste electrode for sensitive determination of hydrogen peroxide and glucose.
abstract: Gallium hexacyanoferrate (GaHCFe) and graphite powder were homogeneously dispersed into n-dodecylpyridinium hexafluorophosphate and paraffin to fabricate GaHCFe modified carbon ionic liquid paste electrode (CILPE). Mixture experimental design was employed to optimize the fabrication of GaHCFe modified CILPE (GaHCFe-CILPE). A pair of well-defined redox peaks due to the redox reaction of GaHCFe through one-electron process was observed for the fabricated electrode. The fabricated GaHCFe-CILPE exhibited good electrocatalytic activity towards reduction and oxidation of H2O2. The observed sensitivities for the electrocatalytic oxidation and reduction of H2O2 at the operating potentials of +0.8 and -0.2V were about 13.8 and 18.3 mA M(-1), respectively. The detection limit (S/N=3) for H2O2 was about 1 μM. Additionally, glucose oxidase (GOx) was immobilized on GaHCFe-CILPE using two methodology, entrapment into Nafion matrix and cross-linking with glutaraldehyde and bovine serum albumin, in order to fabricate glucose biosensor. Linear dynamic rage, sensitivity and detection limit for glucose obtained by the biosensor fabricated using cross-linking methodology were 0.1-6mM, 0.87 mA M(-1) and 30 μM, respectively and better than those obtained (0.2-6mM, 0.12 mA M(-1) and 50 μM) for the biosensor fabricated using entrapment methodology.
authors.affiliation: Department of Chemistry, Institute for Advanced Studies in Basic Sciences, P.O. Box 45195-1159, Gava Zang, Zanjan, Iran. Electronic address: haghighi@iasbs.ac.ir.
authors.forename: Behzad
authors.initials: B
authors.lastname: Haghighi
authors.affiliation: Department of Chemistry, Institute for Advanced Studies in Basic Sciences, P.O. Box 45195-1159, Gava Zang, Zanjan, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Khosravi
authors.affiliation: Department of Chemistry, Institute for Advanced Studies in Basic Sciences, P.O. Box 45195-1159, Gava Zang, Zanjan, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Barati
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D002244:Carbon / Q000737:chemistry; D002417:Cattle; D055664:Electrochemical Techniques; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D005295:Ferrocyanides / Q000737:chemistry*; D005708:Gallium / Q000737:chemistry*; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000737:chemistry / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000032:analysis*; D052578:Ionic Liquids / Q000737:chemistry*; D010084:Oxidation-Reduction; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism
chemical_list: D004800:Enzymes, Immobilized; D005295:Ferrocyanides; D052578:Ionic Liquids; C116383:ferrocyn; D012710:Serum Albumin, Bovine; D002244:Carbon; D006861:Hydrogen Peroxide; D005708:Gallium; D005949:Glucose Oxidase; D005947:Glucose
keywords: Carbon ionic liquid paste electrode; Electrochemical sensor; Gallium hexacyanoferrate modified electrode; Glucose; Hydrogen peroxide