Reference electrodes of electrochemical sensors
A reference electrode of an electrochemical sensor includes a substrate having a well, a channel, and a conductive element. The well extends from a first surface of a substrate towards a second surface of the substrate. The channel is within the substrate. A longitudinal axis of the channel may be substantially perpendicular to a longitudinal axis of the well. The channel has a first end connected to the well and a second end that is in contact with the conductive element. The channel and the wells form a flow path of a conductive medium. The flow path may be coupled to a manipulating element such as an agitating element or heating element that promotes flow of the membrane.
1 . A reference electrode in an electrochemical sensor, the reference electrode comprising:
a substrate including an inner wall defining a flow path of a reference medium, the flow path arranged in the substrate;
an electrically conductive element in the substrate, wherein the electrically conductive element is in contact with the reference medium in the flow path; and
an agitating element arranged on the inner wall of the substrate and configured to change a size or shape of at least part of the flow path of the reference medium,
wherein the reference medium is distinct from an analyte-containing sample fluid that contacts one or more working electrodes of the electrochemical sensor, and
wherein the reference electrode establishes a reference potential for electrochemical measurements involving the one or more working electrodes.
2 . The reference electrode of claim 1 , wherein the agitating element is configured to change the size or shape of at least part of the flow path by applying a mechanical stress onto the inner wall of the flow path in response to an electrical field applied on the agitating element.
3 . The reference electrode of claim 1 , wherein the agitating element is configured to change the size or shape of at least part of the flow path by applying a mechanical stress onto the inner wall of the flow path in response to a radio frequency signal applied on the agitating element.
4 . The reference electrode of claim 1 , wherein the agitating element comprises an electroactive polymer or a piezoelectric material.
5 . The reference electrode of claim 1 , wherein the flow path includes:
a well in the substrate, the well extending from a first surface of the substrate towards a second surface of the substrate, wherein the first surface is opposite the second surface; and
a channel arranged in the substrate and between the first surface and the second surface, wherein a first end of the channel is connected to the well, a second end of the channel is exposed to the electrically conductive element, and the first end is opposite the second end.
6 . The reference electrode of claim 5 , wherein the agitating element is arranged on a wall of the channel and is configured to change a size or shape of the channel.
7 . The reference electrode of claim 6 , further comprising an additional agitating element arranged on a wall of the well and configured to change a size or shape of the well.
8 . The reference electrode of claim 5 , wherein the flow path further includes: a second well in the substrate, the second well extending from the first surface towards the second surface, wherein the second end of the channel is connected to the second well, and the first end is opposite the second end.
9 . An electrochemical sensor, comprising:
one or more working electrodes in a substrate, wherein a working electrode of the one or more working electrodes includes a working well configured to be at least partially filled with an ion selective membrane that contacts a first electrically conductive element of the working electrode; and
a reference electrode electrically coupled to the one or more working electrodes, the reference electrode comprising:
a flow path of a reference medium defined by an inner wall of the substrate, the flow path arranged in the substrate, wherein the reference medium is different than the ion selective membrane,
an electrically conductive element in the substrate, wherein the electrically conductive element is in contact with the flow path, and
an agitating element arranged on the inner wall of the substrate and configured to change a size or shape of at least part of the flow path, wherein the reference electrode establishes a reference potential for electrochemical measurements involving the one or more working electrodes.
10 . The electrochemical sensor of claim 9 , wherein the agitating element is configured to change the size or shape of at least part of the flow path by applying a mechanical stress onto the inner wall of the flow path in response to an electrical field applied on the agitating element.
11 . The electrochemical sensor of claim 9 , wherein the agitating element is configured to change the size or shape of at least part of the flow path by applying a mechanical stress onto the inner wall of the flow path in response to a radio frequency signal applied on the agitating element.
12 . The electrochemical sensor of claim 9 , wherein the agitating element comprises an electroactive polymer or a piezoelectric material.
13 . The electrochemical sensor of claim 9 , wherein the flow path includes:
a well in the substrate, the well extending from a first surface of the substrate towards a second surface of the substrate, wherein the first surface is opposite the second surface; and
a channel arranged in the substrate and between the first surface and the second surface, wherein a first end of the channel is connected to the well, a second end of the channel is exposed to the electrically conductive element, and the first end is opposite the second end.
14 . The electrochemical sensor of claim 13 , wherein the agitating element is arranged on a wall of the channel or on a wall of the well.
15 . The electrochemical sensor of claim 13 , wherein the flow path further includes:
a second well in the substrate, the second well extending from the first surface towards the second surface, wherein the second end of the channel is connected to the second well.
16 . The electrochemical sensor of claim 9 , wherein the one or more working electrodes includes a first working electrode and a second working electrode, and a portion of the flow path is between the first working electrode and the second working electrode.