Microfluidic devices and methods of manufacture thereof

Abstract

A microfluidic device comprising: a substrate having a microfluidic channel, an electrically conductive feature comprising an electrically conductive layer arranged on a primer layer and positioned with reference to the microfluidic channel, wherein the primer layer comprises: (i) an organic polymer selected from the group consisting of: (a) a homopolymer or copolymer including a vinyl lactam repeating unit, (b) a cellulose ether; (c) polyvinyl alcohol; and (d) unmodified or modified gelatin; and (ii) a porous particulate material, the organic polymer being dispersed in the porous particulate material, is provided. Methods for manufacturing the microfluidic devices and their use in a number of applications are also provided.

1 . A microfluidic device, comprising:
 a substrate having a microfluidic channel; and   an electrically conductive feature comprising an electrically conductive layer arranged on a primer layer and positioned with reference to the microfluidic channel,   wherein the primer layer comprises a polymer and a porous particulate material, and the porous particulate material is dispersed in the polymer, and   wherein the microfluidic channel comprises a side wall portion that joins an upper surface of the substrate at a rim and a lateral separation δ exists between the rim of the microfluidic channel and the edge of the electrically conductive layer.   
     
     
         2 . The microfluidic device of  claim 1 , wherein the primer layer comprises at least 70% by weight of the porous particulate material, based on a total weight of the polymer and porous particulate material. 
     
     
         3 . The microfluidic device of  claim 1 , wherein the primer layer comprises at least 90% by weight of the porous particulate material, based on a total weight of the polymer and porous particulate material. 
     
     
         4 . The microfluidic device of  claim 1 , wherein the primer layer comprises up to 30% by weight of the polymer, based on a total weight of the polymer and porous particulate material. 
     
     
         5 . The microfluidic device of  claim 1 , wherein the primer layer comprises up to 10% by weight of the polymer, based on a total weight of the polymer and porous particulate material. 
     
     
         6 . The microfluidic device of  claim 1 , wherein the polymer is an organic polymer. 
     
     
         7 . The microfluidic device of  claim 1 , wherein the substrate is a thermoplastic organic polymer. 
     
     
         8 . The microfluidic device of  claim 1 , wherein the substrate is a silica glass. 
     
     
         9 . The microfluidic device of  claim 6 , wherein the organic polymer of the primer layer comprises hydrophilic functional groups. 
     
     
         10 . The microfluidic device of  claim 6 , wherein the organic polymer of the primer layer is cross-linked. 
     
     
         11 . The microfluidic device of  claim 1 , wherein the porous particulate material comprises a molecular sieve having a pore volume from 0.2-1.20 ml/g. 
     
     
         12 . The microfluidic device of  claim 1 , wherein the porous particulate material is alumina boehmite. 
     
     
         13 . The microfluidic device of  claim 1 , wherein the porous particulate material is silica. 
     
     
         14 . The microfluidic device of  claim 1 , wherein the porous particulate material is a zeolite. 
     
     
         15 . The microfluidic device of  claim 1 , wherein the electrically conductive layer comprises metal. 
     
     
         16 . The microfluidic device of  claim 1 , wherein the electrically conductive layer comprises a conductive form of carbon. 
     
     
         17 . The microfluidic device of  claim 1 , wherein the electrically conductive layer comprises a conductive metal oxide.