Three-dimensional metal ion sensor arrays on printed circuit boards

Abstract

An electronic device includes a substrate and a plurality of sensors. Each sensor is disposed in a well over the substrate and includes a working electrode, an inner filling solution disposed thereover, and an ion-selective membrane. The working electrode is in contact with the substrate and the ion-selective membrane is disposed over the inner filling solution and substantially seals the well.

What is claimed is: 
     
         1 . An electronic device, comprising:
 a) a substrate; and   b) a plurality of sensors, each disposed within a well over the substrate and comprising:
 i) a working electrode in contact with the substrate; 
 ii) an inner filling solution disposed over the working electrode; and 
 iii) an ion-selective membrane disposed over the inner filling solution and substantially sealing the well. 
   
     
     
         2 . The electronic device of  claim 1 , further comprising a silver chloride coating on the working electrode. 
     
     
         3 . The electronic device of  claim 1 , wherein the inner filling solution comprises or consists essentially of a hydrogel. 
     
     
         4 . The electronic device of  claim 1 , wherein the ion-selective membrane comprises polyvinyl chloride. 
     
     
         5 . The electronic device of  claim 1 , further comprising:
 c) a second plurality of sensors, each disposed within a well under the substrate and comprising:
 i) a working electrode in contact with the substrate; 
 ii) an inner filling solution disposed over the working electrode; and 
 iii) an ion-selective membrane disposed over the inner filling solution and substantially sealing the well. 
   
     
     
         6 . The electronic device of  claim 1 , further comprising a cover disposed over a sub-array of the plurality of sensors, the cover comprising or consisting essentially of solder or a shape-memory alloy. 
     
     
         7 . The electronic device of  claim 1 , further comprising, electrically connected to at least one sensor, at least one of an amplifier, a conditioner, a microprocessor, a memory device, a power source, or a transmitter. 
     
     
         8 . The electronic device of  claim 1 , wherein each well is disposed within a plate disposed over and in direct contact with the substrate. 
     
     
         9 . The electronic device of  claim 1 , wherein each well comprises a non-vertical sidewall. 
     
     
         10 . The electronic device of  claim 1 , wherein the substrate comprises one of a printed circuit board or a ground plane. 
     
     
         11 . The electronic device of  claim 1 , wherein the inner filling solution comprises a liquid i) having a boiling point higher than 100° C. and ii) capable of conducting ions. 
     
     
         12 . The electronic device of  claim 1 , wherein a first sensor further comprises an ion-conductive filter disposed over the ion-selective membrane. 
     
     
         13 . The electronic device of  claim 1 , further comprising a micro-fluidic front end for delivering a sample solution to the plurality of sensors. 
     
     
         14 . The electronic device of  claim 13 , wherein the micro-fluidic front end comprises a micro-fluidic channel for temporally separating particles of different mass in the sample solution. 
     
     
         15 . The electronic device of  claim 1 , wherein the plurality of sensors is arranged in a two-dimensional array. 
     
     
         16 . The electronic device of  claim 15 , wherein the two-dimensional array temporally separates particles of different mass in a sample solution. 
     
     
         17 . The electronic device of  claim 1 , wherein the plurality of sensors is arranged in a three-dimensional array.