Page 42 - Optofluidics Fundamentals, Devices, and Applications

Basic Micr ofluidic and Soft Lithographic Techniques 23

Direction of flow

2 mm
FIGURE 2-7 Photograph showing a microfl uidic device we used for generating
gradients of different dyes in solution. The three incoming channels (top part of
the photograph) were connected to syringes via tubings (not visible). After
combining the streams into a single, wide channel (bottom of the photograph),
a gradient was formed across the channel, perpendicular to the direction of fl ow.
(Adapted with permission from S. K. W. Dertinger, D. T. Chiu, N. L. Jeon, and
G. M. Whitesides, “Generation of gradients having complex shapes using
microfluidic networks,” Anal. Chem., 73, (2001), 1240–1246. Copyright
2001 American Chemical Society.)

4. Cooling the channels to form solid metal microstructures.
5. Deforming the solder-filled system of channels into nonpla-
nar structures (if desired).

Next, we will describe two components fabricated using this method.