Patent ID: 7534315

Claim:
A method for providing a dialysis membrane in a fluid microchannel, comprising the steps of: providing a fluid channel network, wherein said fluid channel network comprises one or more fluid microchannels, and means for introducing a sample solution into said fluid channel network, and means for extracting a fluid solution from said fluid channel network; exposing said one or more fluid microchannels to an first aqueous solution, comprising water, glacial acetic acid, and 3-(trimethoxysilylpropyl) acrylate and having silane groups, and acrylate groups and wherein said first aqueous solution has a pH of less than 7.0, said first aqueous solution interacting with interior surfaces of said fluid microchannels wherein said silane groups covalently bond to said interior surfaces and wherein said acrylate groups are exposed and disposed toward the interior of said fluid microchannels; displacing said first aqueous solution with a single phase mixture comprising a monomer/solvent solution and a UV photo-initiator; exposing said single phase mixture to a focused and filtered UV laser light source, wherein said UV laser light is incident into said single phase mixture across a narrow defined exposure region bridging one of said microchannels, said UV laser light interacting with said photo-initiator to polymerize said single phase mixture within said exposure region in a phase-separation polymerization process to provide a porous polymer membrane, said porous polymer membrane bonding to said exposed acrylate groups thereby fixing said porous polymer membrane to said microchannel interior surface within said exposure region; flushing said fluid network and said porous polymer membrane with a solvent to remove remaining unpolymerized single phase mixture, said photo-initiator, and said solvent within said porous polymer membrane, said porous polymer membrane retaining a distribution of pores below a predetermined size; and displacing said solvent with a second aqueous solution.