Electrocatalysis of Hemoglobin in ZnO Nanoparticle/Ionic Liquid Composite Film Modified Glassy Carbon Electrode

Abstract

A nanobiocompatible composite containing hemoglobin (Hb), ZnO nanoparticles (nano-ZnO) and ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF 6 ) was fabricated and further modified on the glassy carbon electrode (GCE). The electrochemical behaviours of Hb in the composite film were carefully studied and a pair of quasi-reversible redox peaks appeared in pH 7.0 phosphate buffer solution, which was attributed to the electrode reaction of Hb heme Fe(III)/Fe(II) redox couple. The presences of nano-ZnO and BMIMPF 6 in the film can retain the bioactivity of Hb and greatly enhance the direct electron transfer of Hb. The immobilized Hb showed high stability and good electrocatalytic ability to the reduction of hydrogen peroxide and O 2 .

“Stable-on-the-Table” Biosensors: Hemoglobin-Poly (Acrylic Acid) Nanogel BioElectrodes with High Thermal Stability and Enhanced Electroactivity

“…Most enzymes are usually unstable and the enzyme-electrodes are generally stored at 4 °C. Increased stability of the Hb-PAA electrodes (95% retention in peak current) is comparable to 96% retention reported using Hb loaded onto ZnO nanoparticle/ionic liquid system [ 39 ], 95% retention in graphene/Fe 3 O 4 nanocomposites [ 40 ] at 4 °C, over the same time period. The increased stability observed with Hb-PAA offer opportunities to build better biosensors with enhanced room temperature storage or wide temperature range applications in contrast to denaturation and subsequent loss in the electroactivity of unprotected enzymes.…”

A review on electrodes modified with ionic liquids

“…In particular, IL containing film enables to observe direct electrochemistry of horseradish peroxidase [27,32,77,78,92,94,100,101,137], hemoglobin [76,80,85,86,90,91,97,99,103,113,115,128,136,[159][160][161], myoglobin [83,89,98,113,127,162], cytochrome c [93,104,113,116], catalase [109] and chloroperoxidase [81]. These and other electrodes are capable of mediatorless bioelectrocatalysis of H 2 O 2 electroreduction with immobilized enzymes as horseradish peroxidase [27,32,78,92,95,96,[100][101][102]137], hemoglobin [76,80,…”

“…These and other electrodes are capable of mediatorless bioelectrocatalysis of H 2 O 2 electroreduction with immobilized enzymes as horseradish peroxidase [27,32,78,92,95,96,[100][101][102]137], hemoglobin [76,80,85,90,97,99,103,128,136,[159][160][161], cytochrome c [93,104], myoglobin [83,89,98,127], catalase [109] or chloroperoxidase [81]. Other group of IL containing composite film electrodes modified with horseradish peroxidase [27], hemoglobin [80,86,90,91,128], cytochrome c [116] or chloroperoxidase [81] exhibits catalysis of dioxygen reduction.…”

Electrochemical fabrication of TiO2 nanoparticles/[BMIM]BF4 ionic liquid hybrid film electrode and its application in determination of p-acetaminophen

“…They possess many specific physicochemical properties such as high ionic conductivity, wide electrochemical window, negligible vapor pressure and good thermal stability. Thus, RTILs have been extensively used as useful supporting electrolytes and electrode modifiers for the incorporation of various nanomaterials, for example carbon nanotubes [2][3][4], gold nanoparticles [5,6], nano-CaCO 3 [7,8], nano-carbon [9], ZnO nanoparticles [10,11] and TiO 2 nanoparticles [12], to construct nano-platforms for electrochemistry or electroanalysis. Among these reported electrochemical systems, [BMIM]PF 6 is the commonly adopted ionic liquid for use in aqueous solutions due to its hydrophobic characteristics.…”