Valve and pump for microfluidic systems and methods for fabrication

Abstract

A microfluidic system and method for its fabrication is disclosed comprising an interposed intermediate layer covering the channel-containing layers, said intermediate layers comprising an integral valve made from the intermediate layer material. A microfluidic system and method is also disclosed for actively pumping a fluid through an integrated layered device incorporating the above-mentioned channels, valves in communication with a chamber, the volume of which can be predictably controlled by interaction between a magnetizable assembly placed on pre-selected sides of the chamber.

1 . A microfluidic device comprising: 
 a first layer comprising a channel, said first layer made from a first material; and    a second layer made from a second material, said second layer in intimate contact with the first layer, said second layer comprising an integral valve made from the second material.    
     
     
         2 . The microfluidic device of  claim 1 , further comprising a metal release layer deposited onto the first layer.  
     
     
         3 . The microfluidic device of  claim 2 , wherein the metal release layer comprises gold.  
     
     
         4 . The microfluidic device of  claim 1 , wherein the first material comprises silicon.  
     
     
         5 . The microfluidic device of  claim 1 , wherein the second material is selected from the group consisting of polyimide-, polyscarbonate-, polysulfone-, polyether ether ketone-, polyvinylidene fluoride-containing compounds, and mixtures thereof.  
     
     
         6 . The microfluidic device of  claim 1 , wherein the second material comprises Kapton®.  
     
     
         7 . The microfluidic device of  claim 1 , wherein the integral valve seals a channel present in the microfluidic device when a first channel flow pressure exceeds a second channel flow pressure.  
     
     
         8 . The microfluidic device of  claim 1 , wherein the integral valve is adapted to allow flow from a secondary channel into a first channel when a second channel flow pressure exceeds a primary channel flow pressure.  
     
     
         9 . The microfluidic device of  claim 1 , further comprising a plurality of valves.  
     
     
         10 . A microfluidic device comprising: 
 a multilayered structure, said structure comprising a first layer made from a first layer material and having at least one channel, and a second layer made from a second layer material, said second layer in intimate contact with the first layer, said second layer comprising an integral valve made from the second layer material, and said integral valve aligned and dimensioned to cover a channel.    
     
     
         11 . The microfluidic device of  claim 10 , wherein the second layer is made from a material selected from the group consisting of polyimide-, polyscarbonate-, polysulfone-, polyether ether ketone-, polyvinylidene fluoride-containing compounds, and mixtures thereof.  
     
     
         12 . The microfluidic device of  claim 10 , wherein the second layer material comprises Kapton®.  
     
     
         13 . A method for analyzing an analyte comprising the steps of: 
 providing a microfluidic device comprising a multilayered structure, said structure comprising a first layer made from a first layer material having at least one channel, and a second layer made from a second layer material, said second layer in intimate contact with the first layer, said second layer comprising an integral valve made from the second layer material, said valve aligned and dimensioned to cover a channel;    providing an amount of analyte;    introducing the amount of analyte to the microfluidic device; and    analyzing the analyte.    
     
     
         14 . A method for analyzing an analyte comprising: 
 providing a microfluidic device comprising a first channel-containing layer and a second channel-containing layer with an intermediate layer interposed between, and in intimate contact with the first and second channel-containing layers, said intermediate layer comprising an integral valve aligned and dimensioned to cover at least one channel;    providing an amount of analyte;    introducing the amount of analyte to the microfluidic device; and    analyzing the analyte.    
     
     
         15 . A method for making a microfluidic device, comprising: 
 providing a substrate made from a substrate material;    providing a channel-containing layer;    positioning the channel-containing layer in intimate contact with the substrate;    providing a cover layer made from a cover material;    providing an intermediate layer;    machining the intermediate material to create a flexible structure, said flexible structure dimensioned to cover a channel in the channel-containing layer; and    positioning the intermediate layer in intimate contact between the channel-containing layer and the cover layer.    
     
     
         16 . A microfluidic device comprising: 
 a structure having multiple layers, said structure comprising a first channel in communication with a first valve, said first valve having an outlet in communication with a chamber, said chamber having an outlet in communication with a second valve, said second valve in communication with a second channel.    
     
     
         17 . The microfluidic device of  claim 16 , wherein the first and second channels each have an initial volume, wherein said initial volume can be predictably altered.  
     
     
         18 . The microfluidic device of  claim 16 , further comprising a magnet positioned proximate to a layer or layers positioned over a first side of the chamber.  
     
     
         19 . The microfluidic device of  claim 18 , further comprising an electrical coil structure positioned proximate to at least one layer positioned over a second side of the chamber.  
     
     
         20 . The microfluidic device of  claim 19 , wherein the coil is activated, and such activation will facilitate an increase or decrease in the initial chamber volume.  
     
     
         21 . The microfluidic device of  claim 20 , wherein the increase or decrease in initial chamber volume is predictably regulated to effect a pumping action in the chamber.