Patent ID: 7201833

Claim:
An enclosed hydrophilic matrix device for transport of an aqueous solute, comprising an electrically insulated substrate; a hydrophilic matrix path on the substrate for electro-kinetic transport of the solute, the matrix path having a pair of spaced apart contacting locations for respective electric contact with a source of power for producing an electric potential along the hydrophilic matrix path; an electrode supported on the substrate and having a contact end for connection to the power source and a matrix end for electric contact with the hydrophilic matrix at one of the contacting locations; the hydrophilic matrix being initially dry and including a humectant for increasing a water absorption rate of the matrix; an insulator enclosing the hydrophilic matrix for sealing the matrix between the insulator and the substrate, the insulator being made of a water vapor permeable material impermeable to the solute; and an orifice in the insulator above the matrix for the passage of an aqueous solute through the insulator.