Preparation of the glucose sensor based on three-dimensional ordered macroporous gold film and room temperature ionic liquid

Abstract

A novel type of glucose sensor was fabricated based on a glucose oxidase (GOD)-N,N-dimethtylformamide (DMF)-[BMIm][BF 4 ] composites modified three-dimensional ordered macroporous (3DOM) gold film electrode. The immobilized GOD exhibits a pair of well-defined reversible peaks in 50 mM pH 7.0 phosphate buffer solutions (PBS), which could be attributed to the redox of flavin adenine dinucleotide (FAD) in GOD. The research results show that ionic liquid ([BMIm][BF 4 ]), DMF and 3DOM gold film are crucial for GOD to exhibit a pair of stable and reversible peaks. It is believed that the large active area of 3DOM gold film can increase the amount of immobilized GOD. Simultaneously, the application of IL enhances the stability of GOD and facilitates the electron transfer between GOD and the electrode. The synergetic effect of DMF can help the GOD to maintain its bioactivity better. GOD immobilized on the electrode exhibits the favorable electrocatalytic property to glucose, and the prepared sensor has a linear range from 10 to 125 nM with a detection limit of 3.3 nM at a signal-to-noise ratio of 3σ. The apparent K m (Michaelis-Menten constant) for the enzymatic reaction is 0.018 mM.ionic liquid, glucose oxidase, three-dimensional ordered macroporous gold film, direct electrochemistry, electrochemical catalysis

The electrochemical characterisation of graphite felts

“…The initial studies with GF electrodes have shown very promising limits of detection; typically 10-100 times lower than the EPPG electrode. Note that traditional disc electrodes modified with porous layers have also been shown to give well defined voltammetry peaks leading to better detection limits [30][31][32][33]. This has recently been simulated and explained in detail by Compton and co-workers [34].…”

A review on electrodes modified with ionic liquids

“…In this case, viscous IL consisting of charged species serves as a binder making film mechanically stable. The immobilized conducting elements include the following: multiwalled carbon nanotubes (MWCNTs) [38,93,[104][105][106][107][108], amine-functionalized MWCNTs [109], single-walled carbon nanotubes (SWCNTs) [110][111][112], porous carbon nanofibers [113], graphenes [114], polymer-functionalized graphene sheets [115], gold nanoparticles [116][117][118], PtCo alloy nanoparticles [67,119] and CdTe quantum dots [120]. Perhaps strong interactions between nanoobjects and IL components result in stable film formation and decrease their aggregation enhancing their electrocatalytic reactivity.…”

“…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. Direct electrochemistry of another important enzyme, glucose oxidase immobilized on film electrode containing IL [38,114,117,138,139,158,163] or its mixture with dimethylformamide [117,158,163], was also reported. These and other electrodes were applied for bioelectrocatalysis of glucose [38,75,114,117,119,123,138,138,158,163,164].…”

Third-generation electrochemical biosensor based on nitric oxide reductase immobilized in a multiwalled carbon nanotubes/1-n-butyl-3-methylimidazolium tetrafluoroborate nanocomposite for nitric oxide detection

“…Moreover, the previously reported τ* for enzymatic and hemebased-biosensors that included BMIMBF4 ranged from 4.18 × 10 −12 to 9.07 × 10 −9 mol/cm 2 and 1.39 × 10 −11 to 6.81 × 10 −8 mol/cm 2 , respectively (Tables 1S-2S, Supplementary Material). Both lowest values of surface coverage were obtained for biosensors that did not include nanomaterials in their construction [51,52]. On the other hand, the higher loadings were reported when enzyme immobilization involved carbon nanomaterials [31,53].…”