Patent ID: 7104517

Claim:
A method of controlling flow of liquids in a micro channel structure comprising the steps of: providing a micro channel and a chamber in the microformat, said micro channel structure defining a liquid transportation system that is present on a plate comprising one or more of said liquid transportation systems, wherein the distance between two opposite walls in said micro channel is about ≦1000 μm to about ≦1 μm and the depth of a chamber is about ≦1000 μm to about ≦1 μm; providing in at least one position in said micro channel structure a plug of polymer material which comprises an intelligent polymer having the property of responding to externally applied energy by changing its volume, said polymer material in a first state providing a first volume blocking said micro channel from liquid flow, and in a second state providing a second volume giving pathway for liquid flow; and selectively applying energy of appropriate type and magnitude to the polymer material of a selected one of said at least one plug so as to cause the volume change between said two states, thereby bringing said polymer to a desired one of said first or second states.