Method for forming an electrode-containing device with capillary transport between electrodes

Claim 1

A method for making a device for the determination of activity of an ionic analyte of a liquid, said device including a pair of solid electrodes each constructed to generate therein an electrical potential that is proportional to the analyte activity present in a contacting quantity of said liquid, and flow control means for directing flow of respective quantities of two such liquids each to a different one of said electrodes and to a junction between said liquids, said control means including a member bridging and contacting said two electrodes; the method comprising the steps of (a) providing a first sheet of formable insulative material having a width and length; (b) forming in said sheet a plurality of adjacent channels extending generally the length of said sheet, a surface of one of said channels being configured to transport liquid; (c) superimposing above said formed sheet a second insulative sheet a surface portion of which is channeled to transport liquid and is opposite to and spaced away from said one surface a distance effective to induce capillary flow of the liquid between said portion and said one channel surface; (d) securing said second sheet to said first sheet to define a capillary liquid transport zone extending in the direction of the length of said first sheet; and, in any order, (e) forming apertures extending all the way through said secured first and second sheets; (f) severing individual units from said secured sheets; and (g) completing the manufacture of a plurality of said devices by attaching a pair of said electrodes to an exterior surface of said first sheet of each of said individual units, each of said electrodes being aligned with one of said apertures.

Claim 2

A method for making a device for the determination of activity of an ionic analyte of a liquid, said device including a pair of solid electrodes each constructed to generate therein an electrical potential that is proportional to the analyte activity present in a contacting quantity of said liquid, and flow control means for directing flow of respective quantities of two such liquids each to a different one of said electrodes and to a junction between said liquids, said control means including a member bridging and contacting said two electrodes; the method comprising the steps of (a) providing a first sheet of formable insulative material having a width and length; (b) forming in said sheet a plurality of adjacent channels extending generally the length of said sheet, a surface of one of said channels being configured to transport liquid; (c) superimposing above said formed sheet a second insulative sheet a surface portion of which is channeled to transport liquid and is opposite to and spaced away from said one surface a distance effective to induce capillary flow of the liquid between said portion and said one channel surface; (d) securing said second sheet to said first sheet to define a capillary liquid transport zone extending in the direction of the length of said first sheet; and, in any order, (e) forming apertures extending all the way through said secured first and second sheets; (f) severing individual units from said secured sheets; and (g) completing the manufacture of a plurality of said devices by attaching a pair of said electrodes to an exterior surface of said first sheet of each of said individual units, each of said electrodes being aligned with one of said apertures.