Fabrication of fluidic features within a plastic substrate

1. A method for constructing at least one channel within a preexisting channel of a substrate, the method comprising:

providing a substrate, wherein the substrate comprises a preexisting channel;

introducing a first fluid and a second fluid into the preexisting channel through a plurality of introductory channels, wherein introducing the first and second fluids comprises attaching a control element to the substrate, wherein the control element comprises the plurality of introductory channels, and wherein the first and second fluids are immiscible;

curing the first fluid, wherein curing the first fluid does not cure the second fluid;

removing the uncured second fluid from the substrate, thereby constructing at least one constructed channel within the preexisting channel; and

repeating the introducing, curing, and removing steps, thereby constructing at least one additional channel within the at least one constructed channel.

2. The method of claim 1 , wherein introducing the first and second fluids is repeated at least once to create an alternating pattern of the first and second fluids within the preexisting channel.

3. The method of claim 1 , wherein the first and second fluids are introduced into the preexisting channel in parallel.

4. The method of claim 1 , wherein introducing the first and second fluids is performed with at least two different sets of introductory channels.

5. The method of claim 1 , wherein the at least one constructed channel comprises a channel width, wherein the first fluid is introduced at a different flow rate than the second fluid, and wherein the channel width is based upon, at least in part, the difference in the flow rate for the first and second fluids.

6. The method of claim 5 , wherein the channel width ranges from 100 nanometers to 10 microns.

7. The method of claim 6 , wherein the channel width ranges from 200 nanometers to 1 micron.

8. The method of claim 7 , wherein the channel width is 500 nanometers.

9. The method of claim 1 , wherein the first fluid is curable with ultraviolet radiation, wherein the second fluid is not curable with ultraviolet radiation, and wherein curing the first fluid comprises exposing the first and second fluids within the preexisting channel to ultraviolet radiation.

10. The method of claim 1 , wherein the substrate comprises a plastic material.

11. The method of claim 10 , wherein the plastic material is selected from the group consisting of polycarbonate, polymethyl methacrylate, and polydimethylsiloxane.

12. The method of claim 1 , wherein the at least one constructed channel comprises a shape selected from the group consisting of straight, curved, L shape, V shape, funnel, and zigzag.