Stable enzyme biosensors based on chemically synthesized Au-polypyrrole nanocomposites.

This work describes development and optimization of a generic method for the immobilization of enzymes in chemically synthesized gold polypyrrole (Au-PPy) nanocomposite and their application in amperometric biosensors. Three enzyme systems have been used as model examples: cytochrome c, glucose oxidase and polyphenol oxidase. The synthesis and deposition of the nanocomposite was first optimized onto a glassy carbon electrode (GCE) and then, the optimum procedure was used for enzyme immobilization and subsequent fabrication of glucose and phenol biosensors. The resulting nanostructured polymer strongly adheres to the surface of the GCE electrode, has uniform distribution and is very stable. The method has proved to be an effective way for stable enzyme attachment while the presence of gold nanoparticles provides enhanced electrochemical activity; it needs very small amounts of pyrrole and enzyme and the Au-PPy matrix avoids enzyme leaking. The preparation conditions, Michaelis-Menten kinetics and analytical performance characteristics of the two biosensors are discussed. Optimization of the experimental parameters was performed with regard to pyrrole concentration, enzyme amount, pH and operating potential. These biosensors resulted in rapid, simple, and accurate measurement of glucose and phenol with high sensitivities (1.089 mA/M glucose and 497.1 mA/M phenol), low detection limits (2 x 10(-6)M glucose and 3 x 10(-8)M phenol) and fast response times (less than 10s). The biosensors showed an excellent operational stability (at least 100 assays) and reproducibility (R.S.D. of 1.36%).

[1]  M. L. Mena,et al.  Development of a tyrosinase biosensor based on gold nanoparticles-modified glassy carbon electrodes: Application to the measurement of a bioelectrochemical polyphenols index in wines , 2005 .

[2]  Huaiguo Xue,et al.  A highly stable biosensor for phenols prepared by immobilizing polyphenol oxidase into polyaniline-polyacrylonitrile composite matrix. , 2002, Talanta.

[3]  Guo-Li Shen,et al.  A mediator-free phenol biosensor based on immobilizing tyrosinase to ZnO nanoparticles. , 2006, Analytical biochemistry.

[4]  Madhuri Kumari,et al.  Preparation of conducting fibers via the electrochemical polymerization of pyrrole , 1997 .

[5]  S. Cosnier Biomolecule immobilization on electrode surfaces by entrapment or attachment to electrochemically polymerized films. A review. , 1999, Biosensors & bioelectronics.

[6]  Hak-sung Kim,et al.  Electrochemical characterization of polypyrrole/glucose oxidase biosensor: Part II. Optimal preparation conditions for the biosensor , 1996 .

[7]  Silvana Andreescu,et al.  Correlation of analyte structures with biosensor responses using the detection of phenolic estrogens as a model. , 2004, Analytical chemistry.

[8]  Joseph Wang Nanomaterial-based electrochemical biosensors. , 2005, The Analyst.

[9]  L. Burke,et al.  The electrochemistry of gold: I the redox behaviour of the metal in aqueous media , 1997 .

[10]  J M Pingarrón,et al.  A comparison of different strategies for the construction of amperometric enzyme biosensors using gold nanoparticle-modified electrodes. , 2005, Analytical biochemistry.

[11]  Hak-sung Kim,et al.  Electrochemical characterization of polypyrrole/glucose oxidase biosensor: Part I. Influence of enzyme concentration on the growth and properties of the film , 1996 .

[12]  Joachim P. Spatz,et al.  GOLD-POLYPYRROLE CORE-SHELL PARTICLES IN DIBLOCK COPOLYMER MICELLES , 1998 .

[13]  Songqin Liu,et al.  Renewable phenol biosensor based on a tyrosinase-colloidal gold modified carbon paste electrode , 2003 .

[14]  S. Cosnier,et al.  Development of a PPO-poly(amphiphilic pyrrole) electrode for on site monitoring of phenol in aqueous effluents , 1999 .

[15]  A. Ramanavičius,et al.  Polypyrrole-coated glucose oxidase nanoparticles for biosensor design , 2005 .

[16]  R. Hamers,et al.  Functionalized Vertically Aligned Carbon Nanofibers as Scaffolds for Immobilization and Electrochemical Detection of Redox-Active Proteins , 2006 .

[17]  Zhennan Gu,et al.  Direct electrochemistry of cytochrome c at a glassy carbon electrode modified with single-wall carbon nanotubes. , 2002, Analytical chemistry.

[18]  Dongxue Han,et al.  One-step synthesis of 3D dendritic gold/polypyrrole nanocomposites via a self-assembly method , 2006 .

[19]  C. Nakamura,et al.  Monolayers, Langmuir-Blodgett films of carbon nanotubes-cytochrome c conjugates and electrochemistry , 2006 .

[20]  A. Ramanavičius,et al.  Conducting polymer-based nanostructurized materials: electrochemical aspects , 2005, Nanotechnology.

[21]  Michael S. Freund,et al.  Reaction of Pyrrole and Chlorauric Acid A New Route to Composite Colloids , 2001 .

[22]  S. Pandey,et al.  Simultaneous co-immobilization of enzyme and a redox mediator in polypyrrole film for the fabrication of an amperometric phenol biosensor , 2005 .

[23]  L. Niu,et al.  Syntheses of fully sulfonated polyaniline nano-networks and its application to the direct electrochemistry of cytochrome c. , 2006, Biosensors & bioelectronics.

[24]  D. Bélanger,et al.  Optimization of a polypyrrole glucose oxidase biosensor. , 1990, Biosensors & bioelectronics.

[25]  Jay W. Grate,et al.  Nanostructures for enzyme stabilization , 2006 .

[26]  W. Kutner,et al.  Immobilization and electrochemical redox behavior of cytochrome c on fullerene film-modified electrodes. , 2005, Bioelectrochemistry.

[27]  G. S. Wilson,et al.  Biosensors : fundamentals and applications , 1987 .

[28]  Silvana Andreescu,et al.  Trends and challenges in biochemical sensors for clinical and environmental monitoring , 2004 .

[29]  S. Cosnier,et al.  Amperometric detection of phenolic compounds by polypyrrole-based composite carbon paste electrodes. , 2004, Bioelectrochemistry.

[30]  G. S. Wilson,et al.  Electrochemical biosensors: recommended definitions and classification. , 2001, Biosensors & bioelectronics.

[31]  Y. Yagcı,et al.  Preparation of biosensors by immobilization of polyphenol oxidase in conducting copolymers and their use in determination of phenolic compounds in red wine. , 2006, Bioelectrochemistry.

[32]  Asha Chaubey,et al.  Application of conducting polymers to biosensors. , 2002, Biosensors & bioelectronics.

[33]  G. E. De Benedetto,et al.  One-step fabrication of a bienzyme glucose sensor based on glucose oxidase and peroxidase immobilized onto a poly(pyrrole) modified glassy carbon electrode , 1996 .