Ghafar-Zadeh / Sawan CMOS Capacitive Sensors for Lab-on-Chip Applications

A Multidisciplinary Approach
1. Auflage 2010
ISBN: 978-90-481-3727-5
Verlag: Springer-Verlag
Format: PDF
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, 146 Seiten

1.1 Overview of Lab-on-Chip Laboratory-on-Chip (LoC) is a multidisciplinary approach used for the miniaturization, integration and automation of biological assays or procedures in analytical chemistry [1-3]. Biology and chemistry are experimental sciences that are continuing to evolve and develop new protocols. Each protocol offers step-by-step laboratory instructions, lists of the necessary equipments and required biological and/or chemical substances [4-7]. A biological or chemical laboratory contains various pieces of equipment used for performing such protocols and, as shown in Fig. 1.1, the engineering aspect of LoC design is aiming to embed all these components in a single chip for single-purpose applications. 1.1.1 Main Objectives of LoC Systems Several clear advantages of this technology over conventional approaches, including portability, full automation, ease of operation, low sample consumption and fast assays time, make LoC suitable for many applications including. 1.1.1.1 Highly Throughput Screening To conduct an experiment, a researcher fills a well with the required biological or chemical analytes and keeps the sample in an incubator for some time to allowing the sample to react properly. Afterwards, any changes can be observed using a microscope. In order to quickly conduct millions of biochemical or pharmacolo- cal tests, the researchers will require an automated highly throughput screening (HTS) [8], comprised of a large array of wells, liquid handling devices (e.g., mic- channel, micropump and microvalves [9-11]), a fully controllable incubator and an integrated sensor array, along with the appropriate readout system.

Ebrahim Ghafar-Zadeh received the BSc and MSc degrees in Electrical Engineering from KNT and Tehran Universities, Tehran, Iran, in 1992 and 1994, respectively. In 1994 he joints the electrical engineering department at SCU University, Ahvaz, Iran as faculty memeber. During 2004-2008, he pursued a PhD degree in electrical engineering at Ecole Polytechnique de Montreal, Canada. In January 2008 and September 2008, he received two fellowship award from NSERC Canada and ReSMiQ Quebec, Canada which allowed him to continue his research for fully integrated bacteria detection. The research interests of Dr. Ghafar-zadeh include the circuit and system design, implementation and packaging technologies for lab-on-chip applications. Mohamad Sawan received his BSc in Electrical Engineering from Université Laval (1984), and MSc (1986) and PhD (1990) both in Electrical Engineering from Université de Sherbrooke. He then completed post-doctoral training at Montréal's McGill University in 1991, and in that same year, joined École Polytechnique de Montréal, where he is currently a Professor of Microelectronics. Dr. Sawan's scientific interests focus on the design and testing of mixed-signal (analog, digital and RF) circuits and systems; digital and analog signal processing; and the modelling, design, integration, assembly and validation of advanced wirelessly powered and controlled monitoring and measurement techniques. These topics are oriented toward biomedical implantable devices and telecommunications applications. Dr. Sawan is holder of the Canada Research Chair in Smart Medical Devices. He heads the Microsystems Strategic Alliance of Québec - ReSMiQ and is founder of the Eastern Canada Chapter of the IEEE-Solid State Circuits Society. He also founded the International IEEE-NEWCAS conference, co-founded the International Functional Electrical Stimulation Society, and founded the Polystim Neurotechnologies Laboratory at Ecole Polytechnique. He is the editor of Springer mixed-signal letters, Chair of the IEEE Biomedical CAS (BioCAS) Technical Committee, and member of the Biotechnology Council representing the IEEE-CAS Society. He has been awarded seven patents. He received the Barbara Turnbull Award for spinal cord research, the Medal of Merit from the Lebanese President (2005), and the J.-A. Bombardier Award from the Association Francophone pour le savoir (ACFAS). Dr. Sawan is a Fellow of both the Canadian Academy of Engineering and the IEEE.

Autoren/Hrsg.

Ghafar-Zadeh, Ebrahim

Sawan, Mohamad

Inhaltsverzeichnis

1;Contents;6
2;Chapter 1;11
2.1;Introduction;11
2.1.1;1.1 Overview of Lab-on-Chip;11
2.1.1.1;1.1.1 Main Objectives of LoC Systems;11
2.1.1.1.1;1.1.1.1 Highly Throughput Screening;11
2.1.1.1.2;1.1.1.2 Early Detection of Disease;12
2.1.1.1.3;1.1.1.3 Point-of-Care (PoC) Testing;12
2.1.1.1.4;1.1.1.4 Environmental Assessment;13
2.1.2;1.2 From Macro to Micro Bioassays;13
2.1.2.1;1.2.1 Micro-scale Liquid Handling;13
2.1.2.2;1.2.2 Thermal Management in Microenvironment;14
2.1.2.3;1.2.3 DNA Amplification;15
2.1.2.4;1.2.4 Sample Handling;15
2.1.2.5;1.2.5 Advantages of Performing Bioassays in Microscale;18
2.1.3;1.3 CMOS-Based LoC;19
2.1.3.1;1.3.1 Manipulation Methods;20
2.1.3.2;1.3.2 Optical Techniques;22
2.1.3.3;1.3.3 Electrochemical Sensors;24
2.1.3.4;1.3.4 Mechanical Sensors;26
2.1.3.5;1.3.5 Magnetic Sensor;27
2.1.3.6;1.3.6 Temperature Control;28
2.1.3.7;1.3.7 Capacitive Sensing LoC;31
2.1.4;1.4 Objectives and Organization of Book;32
3;Chapter 2;34
3.1;Capacitive Sensing Electrodes;34
3.1.1;2.1 On-Chip Microelectrode Configurations;34
3.1.1.1;2.1.1 Passivated Electrodes;34
3.1.1.2;2.1.2 Unpassivated Electrodes;36
3.1.1.3;2.1.3 Sensitivity-Enhanced Passivated Electrodes;36
3.1.1.4;2.1.4 Quasi Interdigitated Electrodes;36
3.1.1.5;2.1.5 Gold Electrodes on CMOS Chip;37
3.1.1.6;2.1.6 Microfluidic Channel Integrated Atop Sensing Electrodes;37
3.1.2;2.2 Micromachining Gold Electrode on CMOS Chip;38
3.1.3;2.3 Electrical Model of Sensing Electrodes;40
3.1.4;2.4 Summary;42
4;Chapter 3;43
4.1;Capacitive Bio-interfaces;43
4.1.1;3.1 Biochemical Capacitive Sensing Methods;44
4.1.1.1;3.1.1 Hybridization Detection;44
4.1.1.2;3.1.2 Antibody–Antigen Recognition;45
4.1.1.3;3.1.3 Living Cells Monitoring;46
4.1.1.4;3.1.4 Organic Solvent Sensors;48
4.1.1.5;3.1.5 Bacteria Growth Monitoring;49
4.1.1.6;3.1.6 Polyelectrolyte Monolayer;51
4.1.1.7;3.1.7 Detection of Protein Conformation;52
4.1.2;3.2 Design of Recognition Element: An Example for Continuous Glucose Monitoring;53
4.1.2.1;3.2.1 Introduction to Glucokinase-Based Glucose Sensor;54
4.1.2.2;3.2.2 Immobilization of Glucokinase on Gold Electrode;55
4.1.2.3;3.2.3 Glucose Testing;56
4.1.3;3.3 Summary;58
5;Chapter 4;59
5.1;Capacitive Interface Circuits for LoC Applications;59
5.1.1;4.1 LBCS Versus MBCS;59
5.1.1.1;4.1.1 Instant Measurement;59
5.1.1.2;4.1.2 Aqueous Measurement;60
5.1.1.3;4.1.3 On-Chip Sensing Electrodes;61
5.1.1.4;4.1.4 Measurement Time;61
5.1.1.5;4.1.5 RC Model Sample;61
5.1.2;4.2 LBCS Methods;62
5.1.2.1;4.2.1 SC-Based Interface Circuit;62
5.1.2.2;4.2.2 Time Constant Method;63
5.1.2.3;4.2.3 Capacitive Inverter Amplifier;64
5.1.2.4;4.2.4 CBCM Methods;67
5.1.3;4.3 Core–CBCM Interface Circuit;68
5.1.3.1;4.3.1 Principle of CBCM for Sensing Applications;68
5.1.3.2;4.3.2 Two Transistors CBCM Sensor;69
5.1.3.3;4.3.3 Opamp-Based Integrator Incorporated with CBCM Sensor;72
5.1.3.4;4.3.4 Differential Current CBCM Techniques;73
5.1.3.5;4.3.5 Current Mirror Integrated with CBCM Structure;74
5.1.3.5.1;4.3.5.1 Differential Voltage Technique;76
5.1.3.5.2;4.3.5.2 Differential Current Technique;76
5.1.3.5.2.1;Ionic Conductive Solutions;78
5.1.3.5.2.2;Differential Capacitive Sensor;78
5.1.3.5.2.3;Sensor Characteristics;79
5.1.3.5.2.3.1;Linearity;79
5.1.3.5.2.3.2;Integrating Capacitor;80
5.1.3.5.2.3.3;Geometrical Issues of Transistors;80
5.1.3.5.2.3.4;Thermal Issues;81
5.1.3.5.2.4;Calibration Technique;82
5.1.3.5.2.4.1;Off-Chip Resistive Technique;82
5.1.3.5.2.4.2;Adjustable Current Gain;83
5.1.3.5.2.4.3;Further Modification;83
5.1.3.5.2.5;Practical Considerations;84
5.1.4;4.4 Core-CBCM SD Capacitive Sensor;87
5.1.4.1;4.4.1 Definitions;87
5.1.4.2;4.4.2 Charge to Digital Converter;87
5.1.4.3;4.4.3 Discussions;90
5.1.4.4;4.4.4 Circuit Level Simulation Results;91
5.1.4.5;4.4.5 Decoding Technique;92
5.1.4.5.1;4.4.5.1 Simple Decoding Method;92
5.1.4.5.2;4.4.5.2 Optimum Decoding Methods;93
5.1.5;4.5 Core-CBCM Capacitive Sensing System;94
5.1.5.1;4.5.1 A System Level Realization;94
5.1.5.2;4.5.2 Experimental Procedures;95
5.1.6;4.6 Summary;98
6;Chapter 5;99
6.1;Microfluidic Packaging Process;99
6.1.1;5.1 Microfluidic Packaging Methods;99
6.1.1.1;5.1.1 On-Chip Micromachining Procedures;100
6.1.1.2;5.1.2 Adhesive Methods;101
6.1.1.2.1;5.1.2.1 Advantages and Disadvantages;102
6.1.1.3;5.1.3 Rapid Prototyping Techniques;102
6.1.2;5.2 Direct-Write Microfabrication Process;103
6.1.2.1;5.2.1 Direct-Ink Writing;103
6.1.2.2;5.2.2 Fundamentals of DWFP;104
6.1.2.3;5.2.3 Direct-Write Microfluidic Fabrication Process;106
6.1.2.3.1;5.2.3.1 Procedures;106
6.1.2.3.2;5.2.3.2 Fabrication Set-Up;106
6.1.2.3.3;5.2.3.3 Advantages and Disadvantages of DWFP;107
6.1.2.3.4;5.2.3.4 Other Practical Considerations of DWFP;109
6.1.2.3.4.1;Dispensing Model;109
6.1.2.3.4.2;Micro-nozzle;111
6.1.2.3.4.3;Micofluidic Fitting;111
6.1.2.3.4.4;Substrate for DWFP;112
6.1.2.3.4.5;Microfluidic Structure;112
6.1.2.3.4.6;Degassing;113
6.1.3;5.3 Direct-Write Microfluidic Packaging Procedure;113
6.1.3.1;5.3.1 Encapsulation of Bonding Pads and Wires;114
6.1.3.2;5.3.2 Ink Deposition;114
6.1.3.3;5.3.3 Fitting Connections;118
6.1.3.4;5.3.4 Fugitive Dam;118
6.1.3.5;5.3.5 Ink Encapsulation and Filling Process;118
6.1.3.6;5.3.6 Ink Removal and Analyte Injection;118
6.1.4;5.4 Emerging Applications of DWFP;120
6.1.4.1;5.4.1 Microvalve;120
6.1.4.2;5.4.2 Direct-Write Heat Exchanger;122
6.1.4.3;5.4.3 Optical Waveguide for Biosensing Applications;123
6.1.5;5.5 Summary;126
7;Chapter 6;127
7.1;Current Technology and Future Works;127
7.1.1;6.1 Conventional Impedometric and Capacitive Measurement Systems;127
7.1.2;6.2 Handheld Impedance Measurement Systems;130
7.1.3;6.3 Towards Fully Integrated Capacitive Sensing LoC;132
7.1.3.1;6.3.1 Packaging;132
7.1.3.2;6.3.2 Capacitance Characterization;132
7.1.3.3;6.3.3 Electrical Modeling of Biological Sample;133
7.1.3.3.1;6.3.3.1 Generic Microelectronic Circuitry;134
7.1.3.4;6.3.4 Cleaning Procedure;134
7.1.4;6.4 Summary;134
8;References;135