Abstract: A system and method for reducing the number of input/output connections required to connect a microfluidic substrate to an external controller for controlling the substrate. In one example, a microfluidic processing device is fabricated on a substrate having a plurality of N independently controllable components, (e.g., a resistive heating elements) each having at least two terminals. The substrate includes a plurality of input/output contacts for connecting the substrate to an external controller, and a plurality of leads for connecting the contacts to the terminals of the components. The leads are arranged to allow the external controller to supply control signals to the terminals of the components via the contacts using substantially fewer contacts than the total number of component terminals.

Abstract: A system and method for preventing or reducing unwanted heat in a microfluidic of the device while generating heat in selected regions of the device.

Abstract: A system and method for preventing or reducing unwanted heat in a microfluidic of the device while generating heat in selected regions of the device. In one example, current is supplied to a heating element through electric leads, wherein the leads are designed so that the current density in the leads is substantially lower than the current density in the heating element. This may be accomplished using conductive leads which have a cross-sectional area which is substantially greater than the cross-sectional area of the heating element. In another example, unwanted heat in the microfluidic complex is reduced by thermally isolating the electric leads from the microfluidic complex. This may be accomplished by running each lead directly away from the microfluidic complex, through a thermally isolating substrate. After the leads pass through the thermally isolating substrate, they are then routed to the current source.

Abstract: The present invention relates to a valve for use in a microfluidic system. The valve includes a substrate defining an upstream channel and a downstream channel joined by a passage, wherein the passage comprises a first opposed wall disposed at an angle to a central axis of the upstream channel. A thermally responsive substance (TRS) obstructs the passage. At least a portion of the TRS that obstructs the passage abuts the first opposed wall. Upon the actuation of the heat source in thermal contact with the TRS an opening motion of the TRS opens the passage.