PART 3:ELECTROCHEMICAL BIOSENSORS 251
7 NANOMATERIAL-BASED ELECTROCHEMICAL BIOSENSORS&N.Jaffrezic-Renault 251
1 Introduction 251
2 Nanomaterials:Fabrication,Chemical and Physical Properties 252
2.1 Conducting Nanomaterials 252
2.2 Nonconducting Nanomaterials:Magnetic Nanoparticles 254
3 Conception and Modeling of Amplification Effect in Nanomaterial-Based Enzyme Sensors 255
3.1 AuNPs-Based Amperometric Sensors 255
3.2 CNT-Based Amperometric Sensors 258
3.3 MNP-Based Amperometric Biosensors 262
3.4 Potentiometric Sensors 265
3.5 Conductometric and Impedimetric Biosensors 265
4 Conception and Modeling of Amplification Effect in Nanomaterial-Based Immunosensors 267
4.1 AuNP-Based Amperometric Immunosensors 267
4.2 AuNP-Based Potentiometric Sensors 272
4.3 Impedimetric Sensors 273
4.4 Conductometric Sensors 276
5 Conception and Modeling of Amplification Effect in Nanomaterial-Based DNA Biosensors 277
5.1 Amperometric Sensors 277
5.2 Impedimetric Sensors 283
6 Conclusion 284
References 285
8 IoN-SENSITIVE FIELD-EFFECT TRANSISTORS WITH NANOSTRUCTURED CHANNELS AND NANOFARTICLE-MODIFIED GATE SURFACES:THEORY,MODELING,AND ANALYSIS&V.K.Khanna 295
1 Introduction 295
2 Structural Configurations of the Nanoscale ISFET 297
2.1 The Nanoporous Silicon ISFET 297
2.2 The CNT ISFET 298
2.3 The Si-NW ISFET 299
3 Physics of the Si-NW Biosensor 299
3.1 Basic Principle 299
3.2 Analogy with the Nanocantilever 300
3.3 Preliminary Analysis of Micro-ISFET Downscaling to Nano-ISFET 301
3.4 Single-Gate and Dual-Gate Nanowire Sensors 304
3.5 Energy-Band Model of the NW Sensor 305
4 Nair-Alam Model of Si-NW Biosensors 307
4.1 The Three Regions in the Biosensor 307
4.2 Computational Approach 308
4.3 Effect of Nanowire Diameter(d)on Sensitivity at Different Doping Densities,with Air as the Surrounding Medium 310
4.4 Effect of Nanowire Length(L)on Sensitivity at Different Doping Densities,with Air as the Surrounding Medium 310
4.5 Effect of the Fluidic Environment 310
4.6 Overall Model Implications 315
5 pH Response of Silicon Nanowires in Terms of the Site-Binding and Gouy-Chapman-Stern Models 316
6 Subthreshold Regime as the Optimal Sensitivity Regime of Nanowire Biosensors 321
7 Effective Capacitance Model for Apparent Surpassing of the Nernst Limit by Sensitivity of the Dual-Gate NW Sensor 324
8 Tunnel Field-Effect Transistor Concept 326
9 Role of Nanoparticles in ISFET Gate Functionalization 328
9.1 Supportive Role of Nanoparticles 328
9.2 Direct Reactant Role of Nanoparticles 330
10 Neuron-CNT(Carbon Nanotube)ISFET Junction Modeling 332
11 Conclusions and Perspectives 334
Dedication 335
Acknowledgments 335
References 335
9 BIOSENSORS:MODELING AND SIMULATION OF DIFFUSION-LIMITED PROCESSES&L.Rajendran 339
1 Introduction 339
1.1 Enzyme Kinetics 339
1.2 Basic Scheme of Biosensors 340
1.3 The Nonlinear Reaction-Diffusion Equation and Biosensors 340
1.4 Types of Biosensors 342
1.5 Michaelis-Menten Kinetics 343
1.6 Non-Michaelis-Menten Kinetics 343
1.7 Importance of Modeling and Simulation of Biosensors 344
2 Modeling of Biosensors 345
2.1 Michaelis-Menten Kinetics and Potentiometric Biosensors 345
2.2 Michaelis-Menten Kinetics and Amperometric Biosensors 346
2.3 Michaelis-Menten Kinetics and Amperometric Biosensors for Immobilizing Enzymes 348
2.4 Michaelis-Menten Kinetics and the Two-Substrate Model 349
2.5 Non-Michaelis-Menten Kinetics 353
2.6 Other Enzyme Reaction Mechanisms 356
2.7 Kinetics of Enzyme Action 361
2.8 Trienzyme Biosensor 362
3 Microdisk Biosensors 363
3.1 Introduction 363
3.2 Mathematical Formulation of the Problem 364
3.3 First-Order Catalytic Kinetics 366
3.4 Zero-Order Catalytic Kinetics 370
3.5 For All Values of KM 372
3.6 Conclusions 373
4 Microcylinder Biosensors 373
4.1 Introduction 373
4.2 Mathematical Formulation of the Problem 374
4.3 Analytical Solutions of the Concentrations and Current 376
4.4 Comparison with Limiting Case of Rijiravanich's Work 378
4.5 Discussion 379
4.6 Conclusions 381
4.7 PPO-Modified Microcylinder Biosensors 382
5 Spherical Biosensors 383
5.1 Simple Michaelis-Menten and Product Competitive Inhibition Kinetics 383
5.2 Immobilized Enzyme for Spherical Biosensors 385
5.3 Conclusion 386
Appendix:Various Analytical Schemes for Solving Nonlinear Reaction Diffusion Equations 386
A．Basic Concept of the Variational Iteration Method 386
B．Basic Concept of the Homotopy Perturbation Method 387
C．Basic Concept of the Homotopy Analysis Method 388
D．Basic Concept of the Adomian Decomposition Method 391
References 392
INDEX 399