MSA  Vol.5 No.10 , August 2014
Nano-Sized Elements in Electrochemical Biosensors
The emerging nanotechnology has opened novel opportunities to explore analytical applications of the fabricated nano-sized materials. Recent advances in nano-biotechnology have made it possible to realize a variety of enzyme electrodes suitable for sensing application. In coating miniaturized electrodes with biocatalysts, undoubtedly the most of the potential deposition processes suffer from the difficulty in depositing process and reproducible coatings of the active enzyme on the miniature transducer element. The promising prospects can concern to the obtaining of thin protein layers by using, i.e. electrochemical deposition, electrophoretic deposition as well as monolayer methods (Langmuir-Blodgett procedure, Layer-by-LayerLbL). Many aspects dealing with deposition of enzyme by techniques employing electric field are considered, including surface charge of enzyme, and its migration under applied electric filed. The using of nanoscale materials (i.e. nanoparticles, nanowires, nanorods) for electrochemical biosensing has seen also explosive increase in recent years following the discovery of nanotubes. These structures offer a promise in the development of biosensing, facilitating the great improvement of the selectivity and sensitivity of the current methods. Finally, the perspectives in the further exploration of nanoscaled sensors are discussed.

Cite this paper
Cabaj, J. and Sołoducho, J. (2014) Nano-Sized Elements in Electrochemical Biosensors. Materials Sciences and Applications, 5, 752-766. doi: 10.4236/msa.2014.510076.
[1]   Luo, X., Morrin, A., Killard, A.J. and Smyth, M.R. (2006) Application of Nanoparticles in Electrochemical Sensors and Biosensors. Electroanalysis, 18, 319-326.

[2]   Dukhin, A.S. and Dukhin, S.S. (2005) Aperiodic Capillary Electrophoresis Method Using an Alternating Current Electric Field for Separation of Macromolecules. Electrophoresis, 26, 2149-2153.

[3]   Sheldon, R.A. and van Pelt, S. (2013) Enzyme Immobilisation in Biocatalysis: Why, What and How. Chemical Society Reviews, 42, 6223-6235.

[4]   Amman, M. (2014) Electrochemical and Electrophoretic Deposition of Enzymes: Principles, Differences and Application in Miniaturized Biosensor and Biofuel Cell Electrodes. Biosensors and Bioelectronics, 58, 121-131.

[5]   Ammam, M. and Fransaer, J. (2009) AC-Electrophoretic Deposition of Glucose Oxidase. Biosensors and Bioelectronics, 25, 191-197.

[6]   Wang, S.S. and Vieth, W.R. (1973) Immobilization of Whole Cells in a Membraneous Form. Biotechnology and Bioengineering, 15, 93-115.

[7]   Johnston, D.A., Cardosi, M.F. and Vaughan, D.H. (1995) The Electrochemistry of Hydrogen Peroxide on Evaporated Gold/Palladium Composite Electrodes. Manufacture and Electrochemical Characterization. Electroanalysis, 7, 520-526.

[8]   Gao, Z.Q., Binyamin, G., Kim, H.H., Barton, S.C., Zhang, Y.C. and Heller, A. (2002) Electrodeposition of Redox Polymers and Co-Electrodeposition of Enzymes by Coordinative Crosslinking. Angewandte Chemie International Edition, 41, 810-813.<810::AID-ANIE810>3.0.CO;2-I

[9]   Ackermann, Y., Guschin, D.A., Eckhard, K., Shleev, S. and Schuhmann, W. (2010) Design of a Bioelectrocatalytic Electrode Interface for Oxygen Reduction in Biofuel Cells Based on a Specifically Adapted Os-Complex Containing Redox Polymer with Entrapped Trametes Hirsuta Laccase. Electrochemistry Communications, 12, 640-643.

[10]   Chiu, J.Y., Yu, C.M., Yen, M.J. and Chen, L.C. (2009) Glucose Sensing Electrodes Based on a Poly(3,4-Ethylenedioxythiophene)/Prussian Blue Bilayer and Multi-Walled Carbon Nanotubes. Biosensors and Bioelectronics, 24, 2015-2020.

[11]   Almeida, N.F., Beckman, E.J. and Ataai, M.M. (1993) Immobilization of Glucose Oxidase in Thin Polypyrrole Films: Influence of Polymerization Conditions and Film Thickness on the Activity and Stability of the Immobilized Enzyme. Biotechnology and Bioengineering, 42, 1037-1045.

[12]   Matsumoto, N., Chen, X.H. and Wilson, G.S. (2002) Fundamental Studies of Glucose Oxidase Deposition on a Pt Electrode. Analytical Chemistry, 74, 362-367.

[13]   Iwuoha, E.I., Saenzde Villaverde, D., Garcia, N.P., Smyth, M.R. and Pingarron, J.M. (1997) Reactivities of Organic Phase Biosensors. 2. The Amperometric Behaviour of Horseradish Peroxidase Immobilised on a Platinum Electrode Modified with an Electrosynthetic Polyaniline Film. Biosensors and Bioelectronics, 12, 749-761.

[14]   Vidal, J.C., Garcia, E. and Castillo, J.R. (1999) In Situ Preparation of Overoxidized PPy/oPPD Bilayer Biosensors for the Determination of Glucose and Cholesterol in Serum. Sensors and Actuators B, 57, 219-226.

[15]   Ammam, M. and Fransaer, J. (2010) Alternating Current Electrophoretic Deposition of Saccharomyces cerevisiae Cells and the Viability of the Deposited Biofilm in Ethanol Production. Electrochimica Acta, 55, 9125-9131.

[16]   Ammam, M. and Fransaer, J. (2011) Effects of AC-Electrolysis on the Enzymatic Activity of Glucose Oxidase. Electroanalysis, 23, 755-763.

[17]   Ammam, M. and Fransaer, J. (2010) Micro-Biofuel Cell Powered by Glucose/O2 Based on Electro-Deposition of Enzyme, Conducting Polymer and Redox Mediators: Preparation, Characterization and Performance in Human Serum. Biosensors and Bioelectronics, 25, 1474-1480.

[18]   Schnorr, J.M. and Swager, T.M. (2011) Emerging Applications of Carbon Nanotubes. Chemistry of Materials, 23, 646-657.

[19]   Baughman, R.H., Zakhidov, A.A. and de Heer, W.A. (2002) Carbon Nanotubes—The Route toward Applications. Science, 297, 787-792.

[20]   Hrapovic, S., Liu, Y., Male, K.B. and Luong, J.H.T. (2004) Electrochemical Biosensing Platform Using Platinum Nanopartyicles and Carbon Nanotubes. Analytical Chemistry, 76, 1083-1088.

[21]   Girard-Egrot, A.P., Godoy, S. and Blum, L.J. (2005) Enzyme Association with Lipidic Langmuir-Blodgett Films: Interests and Applications in Nanobioscience. Advances in Colloid and Interface Science, 116, 205-225.

[22]   Caseli, L., Moraes, M.L., Zucolotto, V., Ferreira, M., Nobret, T.M., Zaniquelli, M.E.D., Pereira, U. and Oliveira Jr., O.N. (2006) Fabrication of Phytic Acid Sensor Based on Mixed Phytase-Lipid Langmuir-Blodgett Films. Langmuir, 22, 8501-8508.

[23]   Schmidt, T.F., Caseli, L., Viitala, T. and Oliveira Jr., O.N. (2008) Enhanced Activity of Horseradish Peroxidase in Langmuir-Blodgett Films of Phospholipids. Biochimica et Biophysica Acta, 1778, 2291-2297.

[24]   Yin, F., Kafi, A.K.M., Shin, H.K. and Kwon, Y.S. (2005) Human Serum Albumin-Octadecylamine Langmuir-Blodgett Film Formed by Spreading Human Serum Albumin Solution Directly on Subphase’s Interface Covered with a Layer of Octadecylamine. Thin Solid Films, 488, 223-229.

[25]   Caseli, L., Nobre, T.M., Zaniquelli, M.E.D., Zucolotto, V. and Oliveira Jr., O.N. (2008) Using Phospholipid Langmuir and Langmuir-Blodgett Films as Matrix for Urease Immobilization. Journal of Colloid and Interface Science, 319, 100-108.

[26]   Apetrei, C., Alessio, P., Constantino, C.J.L., de Saja, J.A., Rodriguez-Mendez, M.L., Pavinatto, F.J., Fernandes, E.G.R., Zucolotto, V. and Oliveira Jr., O.N. (2011) Biomimetic Biosensor Based on Lipidic Layers Containing Tyrosinase and Lutetium Bisphthalocyanine for the Detection of Antioxidants. Biosensors and Bioelectronics, 26, 2513-2519.

[27]   Cabaj, J., Chyla, A., Jedrychowska, A., Olech, K. and Soloducho, J. (2012) Detecting Platform for Phenolic Compounds-Characteristic of Enzymatic Electrode. Optical Materials, 34, 1677-1681.

[28]   Sun, Q., Zorin, N.A., Chen, D., Chen, M., Lieu, T.X., Myake, J. and Qian, D.J. (2010) Langmuir-Blodgett Films of Pyridyldithio-Modified Multiwalled Carbon Nanotubes as a Support to Immobilize Hydrogenase. Langmuir, 26, 10259-10265.

[29]   Decher, G. and Hong, J.D. (1991) Buildup of Ultrathin Multilayer Films by a Self-Assembly Process: II. Consecutive Adsorption of Anionic and Cationic Bipolar Amphiphiles and Polyelectrolytes on Charged Surfaces. Berichte der Bunsengesellschaft für physikalische Chemie, 95, 1430-1434.

[30]   Decher, G. (1997) Fuzzy Nanoassemblies: Toward Layered Polymeric Multicomposites. Science, 277, 1232-1237.

[31]   Siqueira Jr., J.R., Gasparoto, L.H.S., Crespilho, F.N., Carvalho, A.J.F., Zucolotto, V. and Oliveira Jr., O.N. (2006) Physicochemical Properties and Sensing Ability of Metallophthalocyanines/Chitosan Nanocomposites. Journal of Physical Chemistry B, 110, 22690-22694.

[32]   Jeong, R.A., Hwang, J.Y., Joo, S., Chung, T.D., Vark, S.P., Kang, S.K., Lee, W.Y. and Kim, H.C. (2003) In Vivo Calibration of the Subcutaneous Amperometric Glucose Sensors Using a Non-Enzyme Electrode. Biosensors and Bioelectronics, 19, 313-319.

[33]   Jie, G., Liu, B., Pan, H., Zhu, J.J. and Chen, H.Y. (2007) CdS Nanocrystal-Based Electrochemiluminescence Biosensor for the Detection of Low-Density Lipoprotein by Increasing Sensitivity with Gold Nanoparticle Amplification. Analytical Chemistry, 79, 5574-5581.

[34]   Shi, G.Y., Qu, Y.H., Zhai, Y.Y., Liu, Y., Sun, Z.Y., Yang, J.G. and Jin, L.T. (2007) {MSU/PDDA}n LBL Assembled Modified Sensor for Electrochemical Detection of Ultratrace Explosive Nitroaromatic Compounds. Electrochemistry Communications, 9, 1719-1724.

[35]   Hou, Y., Cheng, Y., Hobson, T. and Liu, J. (2010) Design and Synthesis of Hierarchical MnO2 Nanospheres/Carbon Nanotubes/Conducting Polymer Ternary Composite for High Performance Electrochemical Electrodes. Nano Letters, 10, 2727-2733.

[36]   Cassier, T., Lowack, K. and Decher, G. (1998) Layer-by-Layer Assembled Protein/Polymer Hybrid Films: Nasnoconstruction via Specific Recognition. Supramolecular Science, 5, 309-315.

[37]   Ram, K., Bertoncello, M.P., Ding, H., Paddeu, S. and Nicolini, C. (2001) Cholesterol Biosensors Prepared by Layerby-Layer Technique. Biosensors and Bioelectronics, 16, 849-856.

[38]   Musameh, M., Wang, J., Merkoci, A. and Lin, Y.H. (2002) Low-Potential Stable NADH Detection at Carbon-NanotubeModified Glassy Carbon Electrodes. Electrochemistry Communications, 4, 743-746.

[39]   Dequaire, M., Degrand, C. and Limoges, B. (2000) An Electrochemical Metalloimmunoassay Based on a Colloidal Gold Label. Analytical Chemistry, 72, 5521-5528.

[40]   Sadik, O.A., Aluoch, A.O. and Zhou, A.L. (2009) Status of Biomolecular Recognition Using Electrochemical Techniques. Biosensors and Bioelectronics, 24, 2749-2765.

[41]   Zhang, S., Wang, N., Yu, H., Niu, Y. and Sun, C. (2005) Tailoring the Surface Potential of Gold Nanoparticles with Self-Assembled Monolayers with Mixed Functional Groups. Biochemistry, 67, 15-22.

[42]   Yogeswaran, U. and Chen, S.M. (2008) A Review on the Electrochemical Sensors and Biosensors Composed of Nanowires as Sensing Material. Sensors, 8, 290-313.

[43]   Ajayan, P.M. (1999) Nanotubes from Carbon. Chemical Reviews, 99, 1787-1800.

[44]   Lynam, C., Gilmartin, N., Minett, A.I., O’Kennedy, R. and Wallace, G. (2009) Carbon Nanotube-Based Transducers for Immunoassays. Carbon, 47, 2337-2343.

[45]   Zhao, Y.D., Zhang, W.D., Chen, H., Luo, Q.F. and Li, S.F.Y. (2002) Direct Electrochemistry of Horseradish Peroxidase at Carbon Nanotube Powder Microelectrode. Sensors and Actuators B, 87, 168-172.

[46]   Yamamoto, K., Shi, G., Zhou, T.S., Xu, F., Xu, J.M., Kato, T., Jind, J.Y. and Jin, L.T. (2003) Study of Carbon Nanotubes-HRP Modified Electrode and Its Application for Novel On-Line Biosensors. Analyst, 128, 249-254.

[47]   Wang, J.X., Li, M.X., Shi, Z.J., Li, N.Q. and Gu, Z.N. (2002) Direct Electrochemistry of Cytochrome c at a Glassy Carbon Electrode Modified with Single-Wall Carbon Nanotubes. Analytical Chemistry, 74, 1993-1997.

[48]   Davis, J.J., Coles, R.J., Allen, H. and Hill, O. (1997) Protein Electrochemistry at Carbon Nanotube Electrodes. Journal of Electroanalytical Chemistry, 440, 279-282.

[49]   Guiseppi-Elie, A., Lei, C.H. and Baughman, R.H. (2002) Direct Electron Transfer of Glucose Oxidase on Carbon Nanotubes. Nanotechnology, 13, 559-564.

[50]   Dechakiatkrai, C., Chen, J., Lynam, C., Min, S.K., Kim, S.J., Phanichphant, S. and Wallace, G.G. (2008) Direct Ascorbic Acid Detection with Ferritin Immobilized on Single-Walled Carbon Nanotubes. Electrochemical and SolidState Letters, 11, K4-K6.

[51]   Chen, R.J., Zhang, Y.G., Wang, D.W. and Dai, H.J. (2001) Noncovalent Sidewall Functionalization of Single-Walled Carbon Nanotubes for Protein Immobilization. Journal of the American Chemical Society, 123, 3838-3839.

[52]   Rubianes, M.D. and Rivas, G.A. (2003) Carbon Nanotubes Paste Electrode. Electrochemistry Communications, 5, 689-694.

[53]   Perez, B., Pumera, M., del Valle, M., Merkoci, A. and Alegret, S. (2005) Glucose Biosensor Based on Carbon Nanotube Epoxy Composites. Journal of Nanoscience and Nanotechnology, 5, 1694-1698.

[54]   Pumera, M., Merkoci, A. and Alegret, S. (2006) Carbon Nanotube-Epoxy Composites for Electrochemical Sensing. Sensors and Actuators B, 113, 617-622.

[55]   Wang, J. and Musameh, M. (2004) Carbon Nanotube Screen-Printed Electrochemical Sensors. Analyst, 129, 1-2.

[56]   Sanchez, S., Pumera, M., Cabruja, E. and Fabregas, E. (2007) Carbon Nanotube/Polysulfone Composite Screen-Printed Electrochemical Enzyme Biosensors. Analyst, 132, 142-147.

[57]   Armada, M.P.G., Losada, J., Cuadrado, I., Alonso, B., Gonzalez, B., Casado, C.M. and Zhang, J.B. (2004) Preparation of Biosensors Based in a Siloxane Homopolymer with Interacting Ferrocenes for the Amperometric Detection of Peroxides. Sensors and Actuators B, 101, 143-149.

[58]   Liu, G.D. and Lin, Y.H. (2006) Amperometric Glucose Biosensor Based on Self-Assembling Glucose Oxidase on Carbon Nanotubes. Electrochemistry Communications, 8, 251-256.

[59]   Liu, G.D. and Lin, Y.H. (2006) Carbon Nanotube-Templated Assembly of Protein. Journal of Nanoscience and Nanotechnology, 6, 948-953.

[60]   Qu, F.L., Yang, M.H., Jiang, J.H., Shen, G.L. and Yu, R.Q. (2005) Amperometric Biosensor for Choline Based on Layer-by-Layer Assembled Functionalized Carbon Nanotube and Polyaniline Multilayer Film. Analytical Biochemistry, 344, 108-114.

[61]   Zhao, H.T. and Ju, H.X. (2006) Multilayer Membranes for Glucose Biosensing via Layer-by-Layer Assembly of Multiwall Carbon Nanotubes and Glucose Oxidase. Analytical Biochemistry, 350, 138-144.

[62]   Yu, X., Chattopadhyay, D., Galeska, I., Papadimitrakopoulos, F. and Rusling, J.F. (2003) Peroxidase Activity of Enzymes Bound to the Ends of Single-Wall Carbon Nanotube Forest Electrodes. Electrochemistry Communications, 5, 408-411.

[63]   Patolsky, F., Weizmann, Y. and Willner, I. (2004) Long-Range Electrical Contacting of Redox Enzymes by SWCNT Connectors. Angewandte Chemie International Edition, 43, 2113-2117.

[64]   Pumera, M., Sanchez, S., Ichinose, I. and Tang, J. (2007) Electrochemical Nanobiosensors. Sensors and Actuators B, 123, 1195-1205.

[65]   Cui, Y., Wei, Q.Q., Park, H.K. and Lieber, C.M. (2001) Functional Nanoscale Electronic Devices Assembled Using Silicon Nanowire Building Blocks. Science, 293, 1289-1292.

[66]   Zhou, X.T., Hu, J.Q., Li, C.P., Ma, D.D.D., Lee, C.S. and Lee, S.T. (2003) Silicon Nanowires as Chemical Sensors. Chemical Physics Letters, 369, 220-224.

[67]   Shao, M.W., Yao, H., Zhang, M.L., Wong, N.B., Shan, Y.Y. and Lee, S.T. (2005) Fabrication and Application of Long Strands of Silicon Nanowires as Sensors for Bovine Serum Albumin Detection. Applied Physics Letters, 87, Article ID: 183106.

[68]   Shao, M.W., Shan, Y.Y., Wong, N.B. and Lee, S.T. (2005) Silicon Nanowire Sensors for Bioanalytical Application: Glucose and Hydrogen Peroxide Detectionadv. Advanced Functional Materials, 15, 1478-1482.

[69]   Janata, J. and Blackburn, G.F. (1984) Immunochemical Potentiometric Sensors. Annals of the New York Academy of Sciences, 428, 286-292.

[70]   Janata, J. (1989) Principles of Chemical Sensors. Plenum Press, New York.

[71]   Klabunde, K.J. (2001) Introduction to Nanotechnology. In: Klabunde, K.J., Ed., Nanoscale Materials in Chemistry, John Wiley and Sons, New York.

[72]   Du, J., Yu, X.P. and Di, J.W. (2012) Comparison of the Direct Electrochemistry of Glucose Oxidase Immobilized on the Surface of Au, CdS and ZnS Nanostructures. Biosensors and Bioelectronics, 37, 88-93.

[73]   Zheng, B.Z., Xie, S.P., Qian, L., Yuan, H.Y., Xiao, D. and Choi, M.M.F. (2011) Gold Nanoparticles-Coated Eggshell Membrane with Immobilized Glucose Oxidase for Fabrication of Glucose Biosensor. Sensors and Actuators B, 152, 49-55.

[74]   Hanefeld, U., Gardossi, L. and Magner, E. (2009) Understanding Enzyme Immobilization. Chemical Society Reviews, 38, 453-468.

[75]   Brogan, K.L., Wolfe, K.N., Jones, P.A. and Schoenfisch, M.H. (2003) Direct Oriented Immobilization of F(ab’) Antibody Fragments on Gold. Analytica Chimica Acta, 496, 73-80.

[76]   Rao, S.V., Anderson, K.W. and Bachas, L.G. (1998) Fundamental Review, Oriented Immobilization of Proteins. Microchimica Acta, 128, 127-143.

[77]   Liu, Z.M., Liu, J., Shen, G.L. and Yu, R.Q. (2006) A Reagentless Tyrosinase Biosensor Based on 1,6-Hexanedithiol and Nano-Au Self-Assembled Monolayers. Electroanalysis, 18, 1572-1577.

[78]   Nakanishi, K., Sakiyama, T., Kumada, Y., Immamura, K. and Imanaka, H. (2008) Recent Advances in Controlled Immobilization of Proteins onto the Surface of the Solid Substrate and Its Possible Application to Proteomics. Current Proteomics, 5, 161-175.

[79]   Snabe, T., Rode, G.A., Neves-Petersen, M.T., Buus, S. and Petersen, S.B. (2006) Oriented Coupling of Major Histocompatibility Complex (MHC) to Sensor Surfaces Using Light Assisted Immobilization Technology. Biosensors and Bioelectronics, 21, 1553-1559.

[80]   Madoz-Gúrpide, J., Abad, J.M., Fernández-Recio, J., Vélez, M., Vázquez, L., Gómez-Moreno, C. and Fernández, V.M. (2000) Modulation of Electroenzymatic NADPH Oxidation through Oriented Immobilization of Ferredoxin: NADP+ Reductase onto Modified Gold Electrodes. Journal of the American Chemical Society, 122, 9808-9817.

[81]   Ha, T.H., Jeong, J.Y. and Chung, B.H. (2005) Immobilization of Hexa-Arginine Tagged Esterase onto Carboxylated Gold Nanoparticles. Chemical Communications, 48, 3959-3961.

[82]   Brown, K.R., Fox, A.P. and Natan, M.J. (1996) Morphology-Dependent Electrochemistry of Cytochrome c at Au Colloid-Modified SnO2 Electrodes. Journal of the American Chemical Society, 118, 1154-1157.

[83]   Lin, J., Qu, W. and Zhang, S. (2007) Disposable Biosensor Based on Enzyme Immobilized on Au-Chitosan-Modified Indium Tin Oxide Electrode with Flow Injection Amperometric Analysis. Analytical Biochemistry, 360, 288-293.

[84]   Tangkuaram, T., Ponchio, C., Kangkasomboon, T., Katikawong, P. and Veerasai, W. (2007) Design and Development of a Highly Stable Hydrogen Peroxide Biosensor on Screen Printed Carbon Electrode Based on Horseradish Peroxidase Bound with Gold Nanoparticles in the Matrix of Chitosan. Biosensors and Bioelectronics, 22, 2071-2078.

[85]   Shumyantseva, V.V., Carrara, S., Bavastrello, V., Jason Riley, D., Bulko, T.V., Skryabin, K.G., Archakov, A.I. and Nicolini, C. (2005) Direct Electron Transfer between Cytochrome P450scc and Gold Nanoparticles on Screen-Printed Rhodium-Graphite Electrodes. Biosensors and Bioelectronics, 21, 217-222.

[86]   Abad, J.M., Velez, M., Santamaria, C., Guisan, J.M., Matheus, P.R., Vazquez, L., Gazaryan, I., Gorton, L., Gibson, T. and Fernandez, V.M. (2002) Immobilization of Peroxidase Glycoprotein on Gold Electrodes Modified with Mixed Epoxy-Boronic Acid Monolayers. Journal of the American Chemical Society, 124, 12845-12853.

[87]   Challa, S.S.R.K. (2010) Nanocomposites: Nanomaterials for the Life Sciences. Wiley-VCH, Weinheim.

[88]   Yang, W.W., Wang, J.X., Zhao, S., Sun, Y.Y. and Sun, C.Q. (2006) Multilayered Construction of Glucose Oxidase and Gold Nanoparticles on Au Electrodes Based on Layer-by-Layer Covalent Attachment. Electrochemistry Communications, 8, 665-672.

[89]   Xiao, Y., Patolsky, F., Katz, E., Hainfeld, J.F. and Willner, I. (2003) “Plugging into Enzymes”: Nanowiring of Redox Enzymes by a Gold Nanoparticle. Science, 299, 1877-1881.

[90]   Gao, F.X., Yuan, R., Chai, Y.Q., Chen, S.H., Cao, S.R. and Tang, M.Y. (2007) Amperometric Hydrogen Peroxide Biosensor Based on the Immobilization of HRP on Nano-Au/Thi/Poly (p-Aminobenzene Sulfonic Acid)-Modified Glassy Carbon Electrode. Journal of Biochemical and Biophysical Methods, 70, 407-413.

[91]   Yang, G., Yuan, R. and Chai, Y.Q. (2008) A High-Sensitive Amperometric Hydrogen Peroxide Biosensor Based on the Immobilization of Hemoglobin on Gold Colloid/L-Cysteine/Gold Colloid/Nanoparticles Pt-Chitosan Composite Film-Modified Platinum Disk Electrode. Colloids and Surfaces B, 61, 93-100.

[92]   Tang, L., Zeng, G.M., Shen, G.L., Li, Y.P., Zhang, Y. and Huang, D.L. (2008) Rapid Detection of Picloram in Agricultural Field Samples Using a Disposable Immunomembrane-Based Electrochemical Sensor. Environmental Science & Technology, 42, 1207-1212.

[93]   Turner, M., Golovko, V.B., Vaughan, O.P., Abdulkin, P., Berenguer-Murcia, A., Tikhov, M.S., Johnson, B.F. and Lambert, R.M. (2008) Selective Oxidation with Dioxygen by Gold Nanoparticle Catalysts Derived from 55-Atom Clusters. Nature, 454, 981-983.