Page 6 - Optofluidics Fundamentals, Devices, and Applications
P. 6
Contents
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1-1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1-2 What Is Optofl uidics? A Historical
Perspective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1-3 Fluidic Advantages . . . . . . . . . . . . . . . . . . . . . . 2
1-3-1 Immiscible Fluid-Fluid Interfaces
Are Smooth . . . . . . . . . . . . . . . . . . . . . 2
1-3-2 Diffusion Can Create Controllable
Blend of Optical Properties . . . . . . . . 3
1-3-3 Fluid Can Be an Excellent Transport
Medium . . . . . . . . . . . . . . . . . . . . . . . . 3
1-3-4 Fluid Can Be an Excellent Buoyancy
Mediator . . . . . . . . . . . . . . . . . . . . . . . . 4
1-4 Optical Advantages . . . . . . . . . . . . . . . . . . . . . . 4
1-4-1 Numerous High-Sensitivity Optical
Sensing Techniques Exist . . . . . . . . . . 4
1-4-2 Light Localization Can Occur at
Biologically Interesting Scale . . . . . . 5
1-4-3 Light Can Manipulate Fluids and
Objects Suspended in Fluids . . . . . . . 5
1-5 Future . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 Basic Microfluidic and Soft Lithographic
Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2-1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2-2 Historical Background . . . . . . . . . . . . . . . . . . . 8
2-3 Materials for Fabricating Microfl uidic
Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2-3-1 Mechanical Properties of PDMS . . . . 8
2-3-2 Surface Chemistry of PDMS . . . . . . . 10
2-3-3 Optical Properties of PDMS . . . . . . . . 13
2-4 Fabrication of Microfl uidic Systems
in PDMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2-5 Characteristics of Flow in Microchannels . . . 14
2-5-1 Laminar Flow . . . . . . . . . . . . . . . . . . . . 14
2-5-2 Diffusion . . . . . . . . . . . . . . . . . . . . . . . . 16
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