Intra-body electrode with a poly(3,4-ethylenedioxythiophene)-based coating
Embodiments in accordance with the present disclosure are directed to an apparatus comprising an intra-body electrode, and a poly(3,4-ethylenedioxythiophene) (PEDOT)-based coating. The PEDOT-based coating is on a surface of the intra-body electrode. And, the PEDOT-based coating includes a PEDOT-backbone doped with counter ions and cross-linked to a photoreactive polymer and a photoreactive-hydrophilic polymer.
1 . An apparatus, comprising:
an intra-body electrode; and
a poly(3,4-ethylenedioxythiophene) (PEDOT)-based coating on a surface of the intra-body electrode, the PEDOT-based coating including a PEDOT-backbone doped with tetrafluoroborate (TFB) counter ions and cross-linked to a photoreactive polymer and a photoreactive-hydrophilic polymer;
wherein the intra-body electrode with the PEDOT-based coating is configured to provide a capacitance of at least sixty microfarad per square millimeter (μF/mm 2 ) and to exhibit a relative difference in impedance magnitude at ten kilohertz (kHz) and at ten Hz of five percent or less.
2 . The apparatus of claim 1 , further including an elongate conduit, wherein the intra-body electrode is positioned on an exterior surface of the elongate conduit.
3 . The apparatus of claim 1 , wherein the photoreactive polymer is non-charged and is configured to provide passivation against protein and cell adhesion when the intra-body electrode is implantable, and the intra-body electrode is configured to capture physiological signals.
4 . The apparatus of claim 1 , wherein the intra-body electrode includes a conductive material and the photoreactive-hydrophilic polymer is non-charged and is a hydrogel configured to provide lubricity and wettability to the PEDOT-based coating on the surface of the intra-body electrode.
5 . The apparatus of claim 1 , wherein the capacitance is at least seventy microfarad per square millimeter (μF/mm 2 ).
6 . An apparatus, comprising:
an intra-body electrode; and
a poly(3,4-ethylenedioxythiophene) (PEDOT)-based coating on a surface of the intra-body electrode, the PEDOT-based coating including a PEDOT-backbone doped with tetrafluoroborate (TFB) counter ions, the intra-body electrode with the PEDOT-based coating configured to provide a charge storage capacity of at least 360 microcoulomb per square millimeter (μC/mm 2 ) and up to 902 μC/mm 2 .
7 . The apparatus of claim 6 , wherein the intra-body electrode with the PEDOT-based coating is further configured to provide a total charge storage capacity of at least five hundred microcoulomb per square millimeter (μC/mm 2 ) and up to 902 microcoulomb per square millimeter (μC/mm 2 ).
8 . The apparatus of claim 6 , wherein the intra-body electrode with the PEDOT-based coating is further configured to maintain electrode potentials within a water stability window and minimize electrode polarization under electrical stimuli.
9 . The apparatus of claim 6 , further including:
an elongate conduit that carries electrically conductive wires; and
a plurality of intra-body electrodes positioned on an exterior surface of the elongate conduit and coupled to the electrically conductive wires, the plurality of intra-body electrodes including the intra-body electrode with the PEDOT-based coating and being configured to capture physiological signals and to deliver electrical signals.
10 . The apparatus of claim 6 , wherein the PEDOT-backbone doped with TFB counter ions is cross-linked to a photoreactive polymer and a photoreactive-hydrophilic polymer.
11 . A method, comprising:
a. adding a layer of poly(3,4-ethylenedioxythiophene) (PEDOT)-based polymer on an intra-body electrode using a solution, the layer of PEDOT-based polymer including PEDOT doped with counter ions and cross-linked to a photoreactive polymer, wherein the counter ions include tetrafluoroborate (TFB);
b. incorporating a photoreactive-hydrophilic polymer with the layer of PEDOT-based polymer; and
c. curing the layer of PEDOT-based polymer to the photoreactive-hydrophilic polymer to form a PEDOT-based coating on the intra-body electrode, the PEDOT-based coating including the PEDOT doped with the counter ions and cross-linked to the photoreactive polymer and the photoreactive-hydrophilic polymer;
d. wherein the intra-body electrode with the PEDOT-based coating is configured to provide a capacitance of at least sixty microfarad per square millimeter (μF/mm 2 ) and to exhibit a relative difference in impedance magnitude at ten kilohertz (kHz) and at ten Hz of five percent or less.
12 . The method of claim 11 , wherein incorporating the photoreactive-hydrophilic polymer with the layer of PEDOT-based polymer includes dip coating the intra-body electrode with the layer of PEDOT-based polymer in a solution that includes the photoreactive-hydrophilic polymer dissolved in a solvent.
13 . The method of claim 11 , wherein curing the layer of PEDOT-based polymer to the photoreactive-hydrophilic polymer includes exposing the layer of PEDOT-based polymer with the incorporated photoreactive-hydrophilic polymer on the intra-body electrode to ultraviolet light for a period of time.
14 . The method of claim 11 , further including curing an additional amount of the photoreactive polymer to the layer of PEDOT-based polymer.
15 . The method of claim 11 , further including forming the solution by dissolving a 3,4-ethylenedioxythiophene (EDOT) monomer in a solvent, wherein the solution includes the EDOT monomer, the photoreactive polymer, the counter ions, and the solvent.
16 . The method of claim 12 , wherein the solution includes tetrabutylammonium tetrafluoroborate (TBATFB), and the solvent includes acetonitrile, and the PEDOT-based coating includes a PEDOT:TFB structure cross-linked to the photoreactive polymer and the photoreactive-hydrophilic polymer.
17 . The method of claim 11 , wherein adding the layer of PEDOT-based polymer includes electrochemically depositing the PEDOT doped with the counter ions on a surface of the intra-body electrode using the solution, wherein the PEDOT doped with the counter ions on the surface of the intra-body electrode includes a PEDOT:tetrafluoroborate (TFB) structure that passively incorporates the photoreactive polymer.
18 . The method of claim 17 , wherein electrochemically depositing the layer includes depositing the PEDOT doped with the counter ions using potentiostatic electrochemical deposition by applying a voltage for a period of time to the intra-body electrode while the intra-body electrode is submerged in the solution.
19 . The method of claim 17 , wherein electrochemically depositing the layer includes depositing the PEDOT doped with the counter ions using cyclic voltammetry between a voltage range and at a scan rate for a number of cycles.
20 . The method of claim 17 , further including curing the PEDOT doped with the counter ions to the passively incorporated photoreactive polymer to form the layer of PEDOT-based polymer including the PEDOT doped with the counter ions cross-linked to the photoreactive polymer.