Electrochemical catalysis and thermal stability characterization of laccase-carbon nanotubes-ionic liquid nanocomposite modified graphite electrode. Biosens Bioelectron

State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Changchun, Jilin 130022, China.
Biosensors & Bioelectronics (Impact Factor: 6.41). 09/2007; 23(1):35-41. DOI: 10.1016/j.bios.2007.03.009
Source: PubMed

ABSTRACT The hydrophobic carbon nanotubes-ionic liquid (CNTs-IL) gel forms a stable modified film on hydrophobic graphite electrode surface. Laccase immobilized on the CNTs-IL gel film modified electrode shows good thermal stability and enhanced electrochemical catalytic ability. The optimal bioactivity occurs with increasing temperature and this optimum is 20 degrees C higher in comparison to free laccase. The improvement of laccase thermal stability may be due to the microenvironment of hydrophobic CNTs-IL gel on graphite electrode surface. On the other hand, the sensitive detection of oxygen has been achieved due to the feasibility of oxygen reduction by both of laccase and nanocomposite of CNTs-IL gel. Furthermore, the laccase hybrid nanocomposite also shows the fast electrochemical response and high sensitivity to the inhibitors of halide ions with the approximate IC50 of 0.01, 4.2 and 87.5 mM for the fluoride, chloride and bromide ions, respectively. It implies the feasibility of laccase modified electrode as an inhibition biosensor to detect the modulators of laccase.

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    • "The use of electrodes prepared from carbon nanotubes and ILs have been reported in a number of articles. One way is to modify the surface of a glassy carbon electrode with a dispersion of CNTs/IL or CNTs /IL/polymer in a suitable solvent [4] [5] [6] [7]. This kind of modified electrode provides a platform for fabrication of biosensors, which shows promising application to detect various biomacromolecules. "
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    ABSTRACT: Based on electric conductivity and wide potential window of ionic liquid (IL) and electric property of single-wall car-bon nanotubes (SWCNTs), composite material of IL-SWCNTs was prepared, glucose sensor was built with this mate-rial for immobilizing glucose oxidase (GOx). It showed good response, sensitivity and stability for long time for glu-cose detection. Linear range for the detection of glucose was from 0.5 × 10 –6 M to 12 × 10 –6 M while detection limit was 6.26 × 10 –8 M (S/N = 3).
    Journal of Analytical Sciences, Methods and Instrumentation 01/2012; 02(02). DOI:10.4236/jasmi.2012.22011
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    • "The ionic liquids (ILs) have a great potential for developing electrochemical application due to the high chemical and electrochemical stability, high ionic conductivity [13]. The advantages of combining IL and CNT were already exploited to develop IL–MWCNT composite gels using different procedures , such as dispersion of CNT/IL in a suitable solvent [14] mixing in a mortar [15], layer-by-layer self-assembly technique [16] or mixing by sonication [17]. Based on the high dispersion of CNT in IL, ease of preparation, high viscosity of IL–CNT gels, the CNT–IL modified electrodes were readily obtained, but few papers were reported for pesticides detection . "
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    ABSTRACT: Low-potential thiocholine (TCh) detection was achieved at ionic liquid–multi-walled carbon nanotube (IL–MWCNT) modified electrodes. Cyclic voltammetry and amperometric characteristics of eight different thiocholine sensors were compared. With an oxidation potential between 0 and +50mV (vs. Ag/AgCl) [EMIM][OTF]-, [EMIM][NTF2]-, [EMIM][TCB]- and [BMIM][BF4]–MWCNT gels offer a substantial decrease of the working potential comparing with other types of thiocholine sensors. Correlation between the physical properties and electrochemical behaviour of IL–MWCNT gels is also reported. Electrochemical impedance spectroscopy (EIS) and pH-dependence experiments suggest the existence of an electrostratic interaction between thiocholine and composite gels which favours the electrochemical reaction. The catalytical rate constant and the diffusion coefficient of thiocholine were calculated from chronoamperometric data. A very good sensitivity between 36 and 45μA/mMcm2 was achieved for acetylthiocholine detection using selected gel-modified sensors.
    Sensors and Actuators B Chemical 09/2010; 150(1):73-79. DOI:10.1016/j.snb.2010.07.040 · 4.10 Impact Factor
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    ABSTRACT: Nanotechnology is playing an important role in the development of biosensors. The exclusive physical and chemical properties of nanomaterials make them exceptionally suitable for designing new and improved sensing devices, especially electrochemical sensors and biosensors. Room temperature ionic liquids (RTILs) are salts that exist in the liquid phase at and around 298 K and are entirely composed of ions: a bulky, asymmetric organic cation and usually an inorganic anion but some ILs also has organic anion. ILs have received much attention as a replacement for traditional volatile organic solvents as they possess many attractive properties such as intrinsic ion conductivity, low volatility, high chemical and thermal stability, low combustibility, and wide electrochemical windows, etc. Due to negligible or nonzero volatility of these solvents, they are considered “greener” for the environment in comparison to volatile organic compounds. ILs have been widely used in electrodeposition, electrosynthesis, electrocatalysis, electrochemical capacitor, lubricants, plasticizers, solvent, lithium batteries, solvents to manufacture nanomaterials, extraction, gas absorption agents etc. [1–4]. This review discusses the electrochemical sensors and biosensors based on carbon nanotubes, metal oxide nanoparticles, and ionic liquid/composite modified electrodes. The main thrust of the review is to present an overview on the advantages of use of RTILs along with nanomaterials for electrochemical sensors and biosensors. Consequently, recent developments and major strategies for enhancing sensing performance have been thoroughly discussed.
    BioNanoScience 09/2013; 3(3). DOI:10.1007/s12668-013-0094-5
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