Disposable working electrode for an electrochemical cell

Abstract

A flow-through electrochemical cell assembly with a disposable working electrode structure, including (a) a perimeter wall defining a sample flow channel including an inlet and an outlet, (b) a sample inlet line in fluid communication with the sample flow channel inlet, (c) a sample outlet line providing fluid communication between the sample flow channel outlet and a remote reference electrode, and (d) a disposable working electrode structure comprising an electrically conductive and electrochemically active working electrode region bound as a layer, directly or indirectly, to an electrically insulating substrate surface. The substrate surface is in fluid-sealing relationship with the sample flow channel, and the working electrode region is in fluid communication with said sample flow channel. The working electrode is vapor deposited, directly or indirectly, onto the organic polymer substrate through a mask, and a fluid seal is formed between said working electrode region and perimeter wall.

1 - 15 . Cancelled.  
     
     
         16 . A method for making a disposable working electrode structure and a sample flow channel for use in an electrochemical cell assembly, said method comprising: 
 (a) vapor depositing electrically conductive and electrochemically active material, directly or indirectly, onto an organic polymer substrate through a mask to form a pattern of a working electrode region, and    (b) forming a fluid seal between said working electrode region and a perimeter wall to define said fluid sample flow channel with said working electrode region in direct fluid contact with said fluid sample flow channel.    
     
     
         17 . The method of  claim 16  in which said vapor deposition is through said mask which mask forms a pattern of an electrically conductive lead interconnecting said working electrode and an electrically conductive contact region forming said disposable working electrode structure.  
     
     
         18 . The method of  claim 16  further comprising, before step (a), vapor depositing an adhesion layer onto said organic polymer substrate through a mask, wherein step (a) is performed by vapor depositing said electrically conductive material and electrochemically active onto said adhesion layer.  
     
     
         19 . The method of  claim 18  in which said adhesion layer is formed of a material selected from the group consisting of titanium, tungsten, chromium, and alloys thereof.  
     
     
         20 . The method of  claim 16  in which said organic polymer is selected from the group consisting of polyester, polycarbonate, polyolefin, polyimide and polyetherimide.  
     
     
         21 . The method of  claim 16  in which said vapor depositing step includes forming said pattern of said working electrode region to be approximately 100 Å to 10,000 Å thick.  
     
     
         22 . The method of  claim 16  in which said working electrode region is bound to said substrate by an intermediate adhesion layer.  
     
     
         23 . The method of  claim 22  in which said intermediate adhesion layer is approximately 50 Å to 5000 Å thick.  
     
     
         24 . The method of  claim 16  in which at least a surface portion of said substrate is exposed to said sample flow channel.  
     
     
         25 . A method for making a flow-through electrical cell assembly comprising: 
 vapor depositing electrically conductive and electrochemically active material, directly or indirectly, onto an organic polymer substrate through a mask to form a pattern of a working electrode region;    providing a reference electrode including a wall having an inlet and an outlet spaced therefrom;    mounting a sealing member to said wall to define a sample flow channel fluidly coupling said inlet and said outlet; and    positioning said substrate, and said working electrode region thereon, on said sealing member such that said working electrode region is in fluid communication with said sample flow channel.    
     
     
         26 . The method of  claim 25  in which said vapor deposition through said mask forms a pattern of an electrically conductive lead interconnecting said working electrode and an electrically conductive contact region forming said disposable working electrode structure.  
     
     
         27 . The method of  claim 25  further comprising vapor depositing an adhesion layer onto said organic polymer substrate through a mask, wherein said vapor depositing step is performed by vapor depositing said electrically conductive material and electrochemically active onto said adhesion layer.  
     
     
         28 . The method of  claim 27  in which said adhesion layer is formed of a material selected from the group consisting of titanium, tungsten, chromium, and alloys thereof.  
     
     
         29 . The method of  claim 25  in which said organic polymer is selected from the group consisting of polyester, polycarbonate, polyolefin, polyimide and polyetherimide.  
     
     
         30 . The method of  claim 25  in which said vapor depositing step includes forming said pattern of said working electrode region to be approximately 100 Å to 10,000 Å thick.  
     
     
         31 . The method of  claim 25  in which said working electrode region is bound to said substrate by an intermediate adhesion layer.  
     
     
         32 . The method of  claim 31  in which said intermediate adhesion layer is approximately 50 Å to 5000 Å thick.  
     
     
         33 . The method of  claim 25  in which at least a surface portion of said substrate is exposed to said sample flow channel.