Microfluidic valve with partially restrained element

Abstract

The invention provides microfluidic devices having valves disposed therein. The valves can be configured as one-way valves. The invention also provides microfluidic pumps using two or more microfluidic valves. The valves can be configured to rest in an open or closed position. The valves also can be single use valves or can be multiple use valves. The valves may be further responsive to actuators, including electromechanical and magnetic actuators.

What is claimed is:  
     
         1 . A microfluidic valve device comprising: 
 a first microfluidic channel disposed in a first layer, the first microfluidic channel having an upper surface;    a second microfluidic channel in a second layer, wherein the second microfluidic channel has at least one dimension smaller than that of the first channel, the second layer having a sealing surface; and    a flap layer disposed between the first microfluidic channel and the second microfluidic channel, the flap layer having a movable flap formed therein, wherein the flap has a closed position sealed against the sealing surface and can open into the first microfluidic channel.    
     
     
         2 . The microfluidic device of  claim 1 , wherein said layers are integral.  
     
     
         3 . The microfluidic device of  claim 1 , wherein said layers are stencil layers.  
     
     
         4 . The microfluidic device of  claim 3 , wherein said stencil layers are polymeric layers.  
     
     
         5 . The microfluidic device of  claim 3 , wherein said stencil layers are adhesive tapes.  
     
     
         6 . The microfluidic device of  claim 1 , wherein the movable flap can contact a second surface of the first layer, wherein such contact restricts fluid flow within the first channel.  
     
     
         7 . The microfluidic device of  claim 1 , further comprising a fourth layer adjacent to the flap layer.  
     
     
         8 . The microfluidic device of  claim 7 , wherein the fourth layer is substantially rigid.  
     
     
         9 . The microfluidic device of  claim 7 , wherein the fourth layer has an aperture disposed therein, wherein the flap can seal against the fourth layer adjacent to the aperture.  
     
     
         10 . The microfluidic device of  claim 1 , wherein the flap has a width that is narrower than the first channel.  
     
     
         11 . The microfluidic device of  claim 1 , wherein the flap is flexible.  
     
     
         12 . The microfluidic device of  claim 1 , wherein the flap is substantially rigid.  
     
     
         13 . The microfluidic device of  claim 12 , wherein the flap has a hinge region.  
     
     
         14 . The microfluidic device of  claim 13 , wherein the hinge region comprises an area with the flap layer with reduced thickness relative to the movable portion of the flap region.  
     
     
         15 . The microfluidic device of  claim 13 , wherein the hinge region is formed from a flexible material.  
     
     
         16 . The microfluidic device of  claim 1 , wherein the flap has an upper flap surface and a lower flap surface and is adhesively coated on either said upper or said lower flap surface.  
     
     
         17 . The microfluidic device of  claim 16 , wherein the flap is adhesively coated on both the upper flap surface and the lower flap surface.  
     
     
         18 . A microfluidic pump comprising: 
 a first microfluidic valve of  claim 1;     a second microfluidic valve of  claim 1;     wherein the first and the second microfluidic valves are in fluid communication with a pumping chamber having an adjustable volume.    
     
     
         19 . The microfluidic pump of  claim 18 , wherein the pumping chamber comprises a cylinder and movable piston assembly.  
     
     
         20 . The microfluidic pump of  claim 18 , further comprising a deformable membrane forming one surface of the pumping chamber.  
     
     
         21 . The microfluidic pump of  claim 20 , further comprising an actuator for deforming the deformable membrane.  
     
     
         22 . The microfluidic pump of  claim 21 , wherein the actuator is electromechanical.  
     
     
         23 . The microfluidic pump of  claim 22 , wherein the electromechanical actuator is a piezoelectric or titanium nickel material.  
     
     
         24 . The microfluidic pump of  claim 20 , further comprising a pressurizable chamber having at least one side formed by the deformable membrane.  
     
     
         25 . The microfluidic pump of  claim 24 , further comprising a pressure regulating pump capable of altering pressure within the pressurizable chamber.  
     
     
         26 . The microfluidic device of  claim 1 , wherein the flap layer includes a material with magnetic susceptibility, the device further comprising a magnetic actuator.