Microfluidic flow devices, methods and systems

摘要

Microfabricated microvalves may be used with liquid-filled control channels and actuated using compact and battery-powered components, without the need for heavier or fixed infrastructure. The disclosed embodiments include microvalves with on-off fluid control with relatively fast response times, coordinated switching of multiple valves, and operation of a biological (enzyme-substrate) assay in a handheld configuration.

主权项

1. A portable micro flow device, comprising:
one or more solenoid actuators, each having a cylindrical plunger with a diameter of less than 5 mm and providing a force of less than 5 N; each of the one or more solenoid actuators having a return spring attached thereto, the return spring being configured to apply a restoring force to move the cylindrical plunger to a home position from an activated position; each of the one or more solenoid actuators being connected to a respective control microfluidic channel to drive a fixed volume of hydraulic fluid sealed within the respective control microfluidic channel; a microcontroller with a programmable component and a drive component connected to the one or more solenoid actuators and configured to operate the one or more solenoid actuators to press on the respective control microfluidic channel to generate a selected pressure in the fixed volume of the hydraulic fluid sealed in the respective control microfluidic channel; the each control microfluidic channel being separated from a respective regulated microfluidic channel by a flexible barrier forming a valve configured to regulate flow in the respective regulated microfluidic channel and such that the valve is opened and closed in response to the one or more solenoid actuators being driven between its home and activated positions, the one or more solenoid actuators drawing a minimum electrical current in the home position, the home position corresponding to a predefined one of the opened and closed positions; the programmable component being configured to operate the valve to perform a microfluidic process control sequence in which the longest cycles coincide with the minimum electrical current, whereby the energy required for operation is minimized; and a movable bracket supporting the one or more solenoid actuators, the bracket being movable with respect to at least the control microfluidic channels such that the one or more solenoid actuators can be positioned with respect to their respective control microfluidic channels and such that the one or more solenoid actuators can be moved away from their respective control microfluidic channels to allow for replacement of the control microfluidic channels.