Development of the electrochemical biosensor for organophosphate chemicals using CNT/ionic liquid bucky gel electrode

Abstract Organophosphorus hydrolase (OPH) immobilized on CNT/ionic liquid (IL) electrodes were prepared by using three different intrinsic kinds of ILs, as binders. CNTs/ILs lead to dramatic electrochemical enhancements with respect to response time, stability, and sensitivity of composite electrodes. In addition, the electrochemical and biocatalytic properties of three-composite electrodes were strongly influenced by different types of ILs used, as verified by cyclic voltammetry and chronoamperometry. These results were attributed to the conformational changes of the microenvironment between the OPH and the composite electrodes within three different types of ILs. In particular, the biocatalytic signals of three OPH/CNT/ILs-modified electrodes increased linearly to the concentration of paraoxon in a wide range of 2–20 μM. These findings provide a deep understanding of the role of each IL on the modified electrodes, enabling to enhance electrochemical properties for biosensors.

[1]  Takuzo Aida,et al.  Molecular Ordering of Organic Molten Salts Triggered by Single-Walled Carbon Nanotubes , 2003, Science.

[2]  J. Wild,et al.  Characterization of organophosphorus hydrolases and the genetic manipulation of the phosphotriesterase from Pseudomonas diminuta. , 1993, Chemico-biological interactions.

[3]  Ying Liu,et al.  Electrochemical and bioelectrochemistry properties of room-temperature ionic liquids and carbon composite materials. , 2004, Analytical chemistry.

[4]  A Mulchandani,et al.  Amperometric thick-film strip electrodes for monitoring organophosphate nerve agents based on immobilized organophosphorus hydrolase. , 1999, Analytical chemistry.

[5]  S. Dong,et al.  Electrochemical characteristics of facile prepared carbon nanotubes-ionic liquid gel modified microelectrode and application in bioelectrochemistry , 2006 .

[6]  Miss A.O. Penney.  (b) , 1974, The New Yale Book of Quotations.

[7]  A Mulchandani,et al.  Biosensor for direct determination of organophosphate nerve agents using recombinant Escherichia coli with surface-expressed organophosphorus hydrolase. 1. Potentiometric microbial electrode. , 1998, Analytical chemistry.

[8]  C. Tran-Minh,et al.  Determination of organophosphorous and carbamate insecticides by flow injection analysis. , 1992, Analytical biochemistry.

[9]  Jianbin Zheng,et al.  Direct electrochemistry of glucose oxidase based on its direct immobilization on carbon ionic liquid electrode and glucose sensing , 2008 .

[10]  S. Yao,et al.  Optical and Bioelectrochemical Characterization of Water‐Miscible Ionic Liquids Based Composites of Multiwalled Carbon Nanotubes , 2006 .

[11]  Félix Pariente,et al.  Determination of organophosphorus and carbamic pesticides with an acetylcholinesterase amperometric biosensor using 4-aminophenyl acetate as substrate , 1994 .