Method for producing a device for electrochemical detection of molecules by way of redox cycling, device therefor and the use thereof

A method for electrochemically detecting redox-active molecules by way of redox cycling comprising:

• providing a device comprising:
• a first electrically conductive electrode disposed on a substrate;
• a passivation layer covering the first electrically conductive electrode at a surface opposite the substrate, the passivation layer having a through-opening;
• a dielectric layer permeable by said redox-active molecules disposed in the through opening on the first electrically conductive electrode;
• and
• a second electrically conductive electrode, having no electrical contact with the first electrode, disposed on the passivation layer and covering the dielectric layer, the second electrically conductive electrode having an access for or being permeable to said redox-active molecules;
• wherein redox cycling of redox-active molecules permeating the dielectric layer takes place at least at portions of the first electrically conductive electrode and second electrically conductive electrode that are in contact with the dielectric layer;
• wherein the dielectric layer is a reservoir for the redox-active molecules present in a solution, a pathway for the redox-active molecules to enter the reservoir being comprised by the second electrically conductive electrode through which said redox-active molecules migrate from an exposed surface of the second electrically conductive electrode through the second electrically conductive electrode into the dielectric layer;
• wherein at least one of the first electrically conductive electrode and second electrically conductive electrode comprises printed electrically conductive particles;
• wherein the passivation layer comprises printed electrically insulating particles;
• and
• wherein the method comprises:
• introducing said solution comprising redox-active molecules into the dielectric layer, and
• applying a voltage to the electrodes so causing alternating reduction and oxidation of the redox-active molecules at the first and second electrically conductive electrodes.

A device for electrochemical detection of redox-active molecules by way of redox cycling, comprising:

• a first electrically conductive electrode disposed on a substrate;
• a passivation layer covering the first electrically conductive electrode at a surface opposite the substrate, the passivation layer having a through-opening;
• a dielectric layer permeable by said redox-active molecules disposed in the through opening on the first electrically conductive electrode;
• and
• a second electrically conductive electrode, having no electrical contact with the first electrode, disposed on the passivation layer and covering the dielectric layer, the second electrically conductive electrode having an access for or being permeable to said redox-active molecules;
• wherein redox cycling of redox-active molecules permeating the dielectric layer takes place at least at portions of the first electrically conductive electrode and second electrically conductive electrode that are in contact with the dielectric layer;
• wherein the dielectric layer is a reservoir for the redox-active molecules present in a solution, a pathway for the redox-active molecules to enter the reservoir being comprised by the second electrically conductive electrode through which said redox-active molecules migrate from an exposed surface of the second electrically conductive electrode through the second electrically conductive electrode into the dielectric layer;
• wherein at least one of the first electrically conductive electrode and second electrically conductive electrode comprises printed electrically conductive particles, and wherein the passivation layer comprises printed electrically insulating particles;
• wherein the second electrically conductive layer is formed with a printable ink comprising electrically conductive particles of a size which are larger than pores in the dielectric layer;
• and
• wherein either the first electrically conductive electrode has no pores, or the first electrically conductive electrode has pores that are smaller than a size of dielectric particles in a printable ink used to form the dielectric layer.