Nanocomposite-based Electronic Tongue: Carbon Nanotube Growth By Chemical Vapor Deposition And Its Application (springer Series In Materials Science)

This book describes the fabrication of a frequency-based electronic tongue using a modified glassy carbon electrode (GCE), opening a new field of applying organic precursors to achieve nanostructure growth. It also presents a new approach to optimizing nanostructures by means of statistical analysis. The chemical vapor deposition (CVD) method was utilized to grow vertically aligned carbon nanotubes (CNTs) with various aspect ratios. To increase the graphitic ratio of synthesized CNTs, sequential experimental strategies based on response surface methodology were employed to investigate the crystallinity of CNTs. In the next step, glucose oxidase (GOx) was immobilized on the optimized multiwall carbon nanotubes/gelatin (MWCNTs/Gl) composite using the entrapment technique to achieve enzyme-catalyzed oxidation of glucose at anodic potentials, which was drop-casted onto the GCE. The modified GCE’s performance indicates that a GOx/MWCNTs/Gl/GC electrode can be utilized as a glucose biosensor with a high direct electron transfer rate between GOx and MWCNTs/Gl. It was possible to use the fabricated biosensor as an electronic tongue thanks to a frequency-based circuit attached to the electrochemical cell. The results indicate that the modified GCE (with GOx/MWCNTs/Gl) holds promising potential for application in voltammetric electronic tongues. Preface 6 Acknowledgements 8 Contents 9 Acronyms 13 1 Introduction 14 Abstract 14 1.1 Nanotechnology in Medical Science 14 1.2 Carbon Nanotubes 15 1.2.1 Synthesis of Carbon Nanotubes 16 1.2.2 Carbon Nanotubes: Surface Modification 16 1.2.3 Optimization of the Growth Condition: Response Surface Methodology 17 1.2.4 Purification of Carbon Nanotubes 17 1.2.5 Functionalization of Carbon Nanotubes 17 1.3 Chemically Modified Electrodes 18 1.4 Glucose Biosensors 18 1.5 Application of Carbon Nanotubes in the Glucose Biosensor 19 1.6 World Demand of the Electrochemical Glucose Biosensor 19 1.7 Aim and Objectives of the Book 20 1.8 Research Scope 20 1.9 Significance of Research on Electrochemical Glucose Biosensors 21 1.10 Organization of the Book 21 References 22 2 Background of the Study 26 Abstract 26 2.1 Structures of Carbon Nanotubes 26 2.2 Generation of Carbon Nanotubes 27 2.2.1 The Arc Discharge Method 27 2.2.2 The Laser Vaporization Method 27 2.2.3 The Chemical Vapor Deposition Method 28 2.2.3.1 Main Parameters on Carbon Nanotubes Produced by Chemical Vapor Deposition Method 28 2.2.3.2 Effects of Temperature on Carbon Nanotubes Growth 29 2.2.3.3 Effects of Carrier Gas Flow Rate on Carbon Nanotubes Growth 29 2.2.3.4 Effects of the Annealing and Vaporization Time on Carbon Nanotubes Growth 29 2.2.3.5 Effects of Catalyst on Carbon Nanotubes Growth: Ferrocene 30 2.3 Fabrication of Glucose Biosensor: The First, Second, and Third Generation 32 2.3.1 Carbon Nanotube-Based Biosensors 33 2.3.2 Functionalization of Carbon Nanotubes 33 2.3.3 Functionalized Carbon Nanotubes to Enhance Electron Transfer Mechanism in Glucose Biosensor 34 2.4 Carbon Nanotube-Based Composites in Glucose Biosensors 38 2.5 Functionalization of Carbon Nanotubes for Other Applications 38 2.5.1 Thermal Applications of Carbon Nanotubes 39 2.5.2 Medical Applications of Carbon Nanotubes 41 2.5.3 Antimicrobial Activity of Carbon Nanotubes 42 2.5.4 Drug Delivery Applications of Carbon Nanotubes 43 2.5.5 Electro-optical Properties of Carbon Nanotubes 43 2.5.6 Mechanical Properties of Carbon Nanotubes 43 2.5.7 Gas Sensors Based on Carbon Nanotubes 44 References 44 3 Experimental Procedures and Materials 51 Abstract 51 3.1 Introduction 51 3.2 Materials 51 3.3 Synthesis of Multilayer Carbon Nanotubes from Camphor Oil by Chemical Vapor Deposition Method 53 3.4 Synthesis of Well-Crystalline Carbon Nanotubes Via Neutralized Cooling Technique by Carbon Vapor Deposition Method 54 3.5 Synthesis of Highly Oriented Vertically Aligned Carbon Nanotubes Via Chemical Vapor Deposition Method 54 3.6 Synthesis of Selective Aspect Ratio Vertically Aligned Carbon Nanotubes Via Carbon Vapor Deposition Method 55 3.7 Optimization of Highly Oriented Vertically Aligned Carbon Nanotubes’ Growth Conditions Using Response Surface Methodology: Design of Experimental Matrix and Experimental Procedure 55 3.8 Characterization of Synthesized Carbon Nanotubes 58 3.8.1 Raman Spectroscopy: Measurement Conditions 59 3.8.2 Thermogravimetric Analysis: Measurement Conditions 59 3.8.3 Field Emission Scanning Electron Microscopy: Measurement Conditions 61 3.8.4 High Resolution Transmission Electron Microscopy: Measurement Conditions 61 3.8.5 Fourier Transform Infrared Spectroscopy: Measurement Conditions 63 3.9 Chemically Modified Electrodes 64 3.9.1 Pretreatment of the Electrodes 64 3.9.2 Preparation of Phosphate Buffer 65 3.9.3 Preparation of Serum Samples and Real Sample Analysis 65 3.9.4 Fabrication of Chemically Modified Electrodes 65 3.10 Fabrication of Glucose Biosensor Based on Vertically Aligned Carbon Nanotubes Composite: GOx/MWCNTs/Gl/GCE 66 3.10.1 Synthesis, Purification, and Optimization of Multi-walled Carbon Nanotubes 66 3.10.2 Fabrication of GOx/MWCNTs/Gl/GCE 66 3.11 Electrochemical Measurements of Modified Electrodes 67 3.11.1 Electrochemical Setup 67 3.11.2 Cyclic Voltammetry 68 3.11.3 Chronoamperometric Response 69 3.12 Integration of Electronic Tongue Based on Frequency Response of GOx/MWCNTs/Gl/GCE Biosensor 69 3.12.1 Square Wave Frequency Measurements of the Electrical Circuit Attached to the Modified Electrodes 70 References 71 4 Results and Discussions 75 Abstract 75 4.1 Fast Synthesis of Multilayer Multi-walled Carbon Nanotubes from Camphor Oil 75 4.2 Synthesis of Well-Crystalline Carbon Nanotubes Via Neutralized Cooling Method 78 4.3 Highly Oriented Vertically Aligned Carbon Nanotubes Via Carbon Vapor Deposition Method 81 4.4 Synthesis of Selective Aspect Ratio Vertically Aligned Carbon Nanotubes Via Carbon Vapor Deposition Method 86 4.5 Optimization of the Growth Condition Using Response Surface Methodology 88 4.5.1 Crystallinity Model: IG/ID-Single-Response Optimization 88 4.5.2 Effect of Deposition Temperature and Concentration of Camphor Oil on Carbon Nanotubes’ Crystallinity 92 4.6 Constant Glucose Biosensor Based on Vertically Aligned Carbon Nanotubes Composites 93 4.6.1 Raman Spectroscopy 93 4.6.2 Field Emission Scanning Electron Microscopy 94 4.6.3 Direct Electron Transfer of GOx/MWCNTs/Gl/GCE 95 4.6.4 Biocatalytic Activity of GOx/MWCNTs/Gl/GC Electrode 96 4.6.5 Amperometric Determination of Glucose on GOx/MWCNTs/Gl/GC Electrode 98 4.6.6 Reproducibility and Stability of the GOx/MWCNTs/Gl/GC Electrode 98 4.6.7 Determination of Glucose in Human Blood Serum and Analytical Recovery of Glucose 99 4.7 Brain-Like Taste Bud Circuit Using the GOx/MWCNTs/Gl/GCE Glucose Biosensor 99 4.7.1 Electrical Circuit of a Taste Bud Inspired Network: Single Membrane 100 References 102 5 Conclusion 105 Abstract 105 5.1 Introduction 105 5.2 Morphology Optimization of Synthesized Carbon Nanotubes 105 5.3 Fast Synthesizing of the Multilayer Carbon Nanotubes 106 5.4 Well-Crystalline Multi-walled Carbon Nanotubes 106 5.5 Highly Oriented Carbon Nanotubes 106 5.6 Selective Aspect Ratio of Carbon Nanotubes 106 5.7 Vectorial Crystal Growth of Oriented Vertically Aligned Carbon Nanotubes 107 5.8 Constant Glucose Biosensor Based on Vertically Aligned Carbon Nanotubes Composites 107 5.9 Brain-Like Taste Bud Circuit Using the GOx/MWCNTs/Gl/GCE Glucose Biosensor 108 5.10 Research Contribution 108 5.11 Recommendations and Future Work 109 Index 110 This book describes the fabrication of a frequency-based electronic tongue using a modified glassy carbon electrode (GCE), opening a new field of applying organic precursors to achieve nanostructure growth. It also presents a new approach to optimizing nanostructures by means of statistical analysis. The chemical vapor deposition (CVD) method was utilized to grow vertically aligned carbon nanotubes (CNTs) with various aspect ratios. To increase the graphitic ratio of synthesized CNTs, sequential experimental strategies based on response surface methodology were employed to investigate the crystallinity of CNTs. In the next step, glucose oxidase (GOx) was immobilized on the optimized multiwall carbon nanotubes/gelatin (MWCNTs/Gl) composite using the entrapment technique to achieve enzyme-catalyzed oxidation of glucose at anodic potentials, which was drop-casted onto the GCE. The modified GCE's performance indicates that a GOx/MWCNTs/Gl/GC electrode ca n be utilized as a glucose biosensor with a high direct electron transfer rate between GOx and MWCNTs/Gl. It was possible to use the fabricated biosensor as an electronic tongue thanks to a frequency-based circuit attached to the electrochemical cell. The results indicate that the modified GCE (with GOx/MWCNTs/Gl) holds promising potential for application in voltammetric electronic tongues Front Matter ....Pages i-xiii Introduction (Amin TermehYousefi)....Pages 1-12 Background of the Study (Amin TermehYousefi)....Pages 13-37 Experimental Procedures and Materials (Amin TermehYousefi)....Pages 39-62 Results and Discussions (Amin TermehYousefi)....Pages 63-92 Conclusion (Amin TermehYousefi)....Pages 93-97 Back Matter ....Pages 99-101