Micromixer apparatus and methods of using same

Abstract

Microfluidics mixing apparatus and methods of using same are disclosed for mixing fluids using increasing centrifugal force as the fluids being mixed traverse a mixing channel. One inventive apparatus comprises a generally planar substrate having a top major surface and a bottom major surface generally parallel to the top major surface, and a cover plate over the top major surface. The substrate has at least one inlet port that routes fluid to the top major surface, and at least one outlet port for mixed fluid. The substrate comprises a mixing channel having a depth measured from the top surface and a width, the mixing channel adapted to route fluids to be mixed therein in laminar flow and in a substantially spiral flow pattern that is parallel to the top surface. Apparatus of the invention can mix fluids flowing serially, or two or more fluids entering the device from different feed channels.

1 - 26 . (canceled)  
   
   
       27 . A microfluidics mixing apparatus for mixing at least two fluids, the apparatus comprising a substrate including one or more fluid feed conduits for routing two or more fluids to be mixed to a continuously curving spiral mixing channel, the mixing channel having a depth and a width, the mixing channel adapted to route fluids to be mixed therein in laminar flow and in a substantially spiral flow pattern that is substantially parallel to a top surface of the substrate, the mixing channel connected to a product conduit.  
   
   
       28 . The microfluidics mixing apparatus of  claim 27  wherein the substrate comprises a top major surface and a bottom major surface generally parallel to the top major surface, the substrate having at least one inlet port that routes fluid to the feed conduits, the substrate having at least one outlet port connected to the product conduit.  
   
   
       29 . The microfluidics mixing apparatus of  claim 27  comprising first and second inlet ports, the first inlet port connected to a first feed conduit, and the second inlet port connected to a second feed conduit, the first and second feed conduits meeting at a mixing point in said mixing channel.  
   
   
       30 . The microfluidics mixing apparatus of  claim 27  wherein one of the feed conduits to the mixing channel is tangent to the substantially spiral flow pattern.  
   
   
       31 . The microfluidics mixing apparatus of  claim 28  wherein the outlet port is centered in the substrate.  
   
   
       32 . The microfluidics mixing apparatus of  claim 27  wherein the mixing channel has a cross-section shape selected from the group consisting of rectangular, circular, oval, and trapezoidal.  
   
   
       33 . The microfluidics mixing apparatus of  claim 27  further comprising a cover plate.  
   
   
       34 . The microfluidics mixing apparatus of  claim 33  wherein the cover plate is transparent.  
   
   
       35 . The microfluidics mixing apparatus of  claim 28  wherein the outlet port connects to a second fluid handling apparatus.  
   
   
       36 . The microfluidics mixing apparatus of  claim 35  wherein the second fluid handling apparatus is like that of  claim 27 .  
   
   
       37 . The microfluidics mixing apparatus of  claim 27  wherein the mixing channel is comprised of a reactive material.  
   
   
       38 . The microfluidics mixing apparatus of  claim 37  wherein the reactive material is selected from the group consisting of catalysts, enzymes, and ligands.  
   
   
       39 . The microfluidics mixing apparatus of  claim 27  wherein the substrate comprises materials selected from the group consisting of silicon, metal, glass, plastic, and combinations, thereof.  
   
   
       40 . The microfluidics mixing apparatus of  claim 28  wherein the inlet port and the outlet port open to the top major surface.  
   
   
       41 . The microfluidics mixing apparatus of  claim 28  wherein the inlet ports and the outlet port open to a peripheral edge of the substrate.  
   
   
       42 . The microfluidics mixing apparatus of  claim 27  wherein the inlet ports and the outlet port lie in the same plane as the mixing channel.  
   
   
       43 . The microfluidics mixing apparatus of  claim 27  wherein the inlet ports and the outlet port lie out-of-plane from the mixing channel.  
   
   
       44 . A method of mixing fluids using the microfluidics mixing apparatus of  claim 27  to mix fluids, the method comprising the steps of: 
 a) selecting fluids to be mixed;    b) selecting a radius of the apparatus and a depth and a width of the mixing channel so as to minimize dead volume; and    c) applying fluids to be mixed and flowing the fluids through the mixing channel.    
   
   
       45 . The method of  claim 44  further comprising a step of selecting an angle θ between two feed conduits feeding the mixing channel.  
   
   
       46 . The method of  claim 44  further comprising a step of monitoring extent of mixing by measuring a property of the mixed fluid.  
   
   
       47 . The method of  claim 44  further comprising a step of reacting a component of a first fluid with a component of a second fluid.  
   
   
       48 . The method of  claim 47  further comprising a step of monitoring extent of reaction of said components.  
   
   
       49 . A method of mixing two or more fluids, the method comprising the steps of 
 a) feeding two or more fluids into a continuously curving spiral microfluidic mixing channel having an outlet; and    b) contacting the fluids through the influence of centrifugal force while flowing through the mixing channel, the mixing channel having a structure that functions to increase centrifugal force on the fluids as they travel toward the outlet, thereby increasing the effective contact area between the fluids while flowing in the mixing channel and enhancing diffusional mixing.    
   
   
       50 . A microfluidics mixing apparatus comprising: 
 a) a substrate and a cover plate combination defining a continuously curving spiral mixing channel, the mixing channel having at least one inlet port and an outlet port; and    b) an apparatus radius and mixing channel depth chosen so as to minimize dead volume.