Dressing for a wound and for electrochemical detection of at least one analyte and method for its manufacture

Abstract

The invention relates to a dressing (100, 200) for a wound. The dressing (100, 200) comprises a flexible substrate (3), at least a working electrode (11), a reference electrode (13) and a counter electrode (15) and a biocompatible conductive layer (17) being intended to be placed in contact with a wound. The electrodes (13, 15, 17) are arranged on the first surface (5) of the flexible substrate (3). The biocompatible conductive layer (17) is configured to allow an electrochemical interaction between at least one analyte and the electrode assembly (9), a concentration of said analyte being determinable from a response generated by this electrochemical interaction. The invention also relates to a method for manufacturing such a dressing (100, 200).

Description

Dressing for a wound and for electrochemical detection of at least one analyte and method for its manufactureField of the Invention

[0001] The present invention relates to a wound dressing and a method for manufacturing such a dressing. The invention relates in particular to the field of dressings intended to improve wound healing and the monitoring of wound healing in a non-invasive manner and by electrochemical detection of at least one analyte.Technological background

[0002] Wounds and their complications are a major problem, both in hospitals and at home. Some wounds, sometimes chronic, heal only slowly, such as those occurring in individuals with diabetes. It is therefore important to be able to improve the treatment and repair times of these types of wounds. In the medical field, innovation related to dressings for monitoring and improving wound healing has seen significant progress through the integration of electronic technologies in dressings.

[0003] These devices are specifically designed either to monitor wound conditions in real time, such as moisture level, temperature, pH, or the presence of infections, or to improve wound repair through targeted electrical stimulation.

[0004] However, these devices require many components, including optical components, and are therefore costly and complex to manufacture. Dressings that release an active ingredient to improve wound repair usually require an electrode to dispense or activate the active ingredient. This again makes the devices complex and costly to manufacture.

[0005] The aim of the present invention is to overcome these drawbacks by providing a dressing that is simple and economical to manufacture, while combining functionalities for the electrochemical detection of at least one analyte.

[0006] The aim of the invention is achieved by virtue of a first aspect of the invention. According to the first aspect of the invention, a dressing for a wound and for the electrochemical detection of at least one analyte is provided. The dressing comprises a biocompatible conductive layer. The biocompatible conductive layer is intended to be placed in contact with a wound. The dressing also comprises a flexible substrate having a first surface and a second surface opposite the first surface, and an electrode assembly. The electrode assembly comprises at least a working electrode, a reference electrode and a counter electrode. Each of the electrodes of the electrode assembly is arranged on the first surface of the flexible substrate. In particular, each of the electrodes of the electrode assembly can be arranged directly on the first surface of the flexible substrate, i.e. without the presence of an intermediate layer between the first surface of theflexible substrate and each of said electrodes. Each of the electrodes of the electrode assembly is respectively electrically connected to at least one connection interface. The at least one connection interface is arranged on the second surface of the flexible substrate. And, the biocompatible conductive layer is in particular directly arranged on, the first surface of the flexible substrate and covers at least the electrode assembly. The biocompatible conductive layer is configured to allow an electrochemical interaction between at least one analyte and the electrode assembly, a concentration of said analyte being determinable from a response generated by this electrochemical interaction. The response generated may, in particular, be a variation in voltage or electrical current.

[0007] The dressing according to the first aspect makes it possible to provide a simple structure, since its structure requires only a limited number of elements. The two surfaces of the flexible substrate are electrically connected. The electrical connection between the two surfaces of the flexible substrate makes it possible to improve the compactness of the dressing. In addition, this simplifies the integration of electrodes and electronic components, for example electronic components at the connection interface. The dressing according to the first aspect therefore makes it possible to reduce the complexity, time and cost of its manufacture.

[0008] Furthermore, the flexible substrate provides a flexible structure. This allows the dressing to conform to irregular or anatomical surfaces of the human body. This can improve the comfort of the patient wearing the dressing. The flexible substrate can contribute to better contact and increased stability between the dressing and the skin, thereby improving the effectiveness of the dressing.

[0009] The biocompatible conductive layer may be configured to transmit charges between the electrodes and the wound, or between the electrodes themselves. In particular, the biocompatible conductive layer may contain at least one electrolyte. The electrolyte may facilitate the transport of charges within the biocompatible conductive layer. The electrolyte enables the flow of an electric current, in particular between the electrodes, through the biocompatible conductive layer. For example, the biocompatible conductive layer may contain an electrolyte such as NaCL

[0010] Depending on the material of the electrodes, in particular the working electrode, the reference electrode and the counter electrode, different types of electrolytes may be preferred. In particular, the biocompatible conductive layer may contain a biocompatible conductive polymer such as polyaniline or polypyrrole.

[0011] lt is also possible to dope the electrolyte contained in the biocompatible conductive layer. In particular, if the electrolyte is a conductive polymer, it is possible to dope it with metal particles, for example silver or gold, or with carbonaceous particles (graphene, carbon nanotubes). Thisdoping has the effect of increasing the conductivity of the electrolyte. In particular, the choice of electrolytes can improve electrochemical interactions with the electrodes, as well as the generation of electrical signals in the electrode assembly.

[0012] The biocompatible conductive layer may also comprise at least one analyte. The analyte is a target substance of the analysis. The analyte may, for example, be oxygen, glucose, lactate or any other relevant analyte.

[0013] The biocompatible conductive layer may also initially contain no analyte. By “initially”, it should be understood that in the dressing upon output from production, in other words before the dressing is applied to a wound, the biocompatible conductive layer contains no analyte. In this embodiment of the invention, the biocompatible conductive layer may be configured to allow the transfer, in particular by electrochemical reaction, of the analyte present in the wound or exudate, from the wound or exudate, to the biocompatible conductive layer, in particular to the electrode assembly, more particularly to the working electrode, the reference electrode and the counter electrode. The biocompatible conductive layer thus configured makes it possible to measure and monitor the concentration of an analyte contained in the wound.

[0014] The biocompatible conductive layer may be configured to transfer one or more analytes from the biocompatible layer to the wound. In particular, these analytes may have properties that improve or accelerate wound repair.

[0015] The biocompatible conductive layer may comprise at least one biomolecule, in particular an enzyme, aptamer or antibody. This at least one biomolecule may improve the targeting of an analyte.

[0016] ln addition, the dressing is suitable for monitoring and improving the repair, in particular the healing, of a wound, by enabling the concentration of an analyte to be determined. In particular, the dressing can be used to monitor the evolution over time of the concentration of an analyte in the biocompatible conductive layer.

[0017] ln the case of oxygen as an analyte, the biocompatible conductive layer may be configured to allow the transfer or flow of oxygen, in particular dissolved oxygen, in the biocompatible conductive layer. In particular, the biocompatible conductive layer may be configured to allow the transfer of oxygen that is reduced to the surface of at least one of the electrodes so as to generate a measurable current.

[0018] l n the case of glucose as an analyte, the biocompatible conductive layer can act as an electrolyte and enable the electrochemical detection of glucose via a specific enzymatic reaction at the working electrode. In particular, the biocompatible conductive layer may comprise a combination of at least one electrolyte and at least one biomolecule. This combination may be adapted to target glucose as an analyte. A combination of a mixture of conductive polymers aselectrolytes with an enzyme as a biomolecule for glucose detection may improve glucose targeting. In particular, a combination of polypyrrole (electrolyte) and glucose oxidase (biomolecule) in the biocompatible conductive layer may improve glucose targeting.

[0019] The biocompatible conductive layer may in particular be made of a gel, and more specifically of a hydrogel. This biocompatible conductive layer may also be made of a foam or of a film. The biocompatible conductive layer may be continuous, formed as a single piece. Alternatively, the biocompatible conductive layer may comprise a plurality of islands of material, such as dots or drops, particularly of hydrogel. In all cases, the biocompatible conductive layer covers at least the electrode assembly, and, in particular, covers the working electrode, the reference electrode and the counter electrode.

[0020] The electrode assembly may be encapsulated by the biocompatible conductive layer. The biocompatible conductive layer prevents direct contact between the electrode assembly and the wound, skin or tissue over which the dressing is applied. The biocompatible conductive layer is intended to be in direct physical contact with the wound or with a surface over which the dressing is applied. The biocompatible conductive layer may also be configured to adhere to the surface with which it is in contact. The monitoring or improvement of wound repair or both may be achieved non-invasively by means of the dressing.

[0021] The biocompatible conductive layer may have a composition that improves the wound healing process. The biocompatible conductive layer may have healing properties. The biocompatible conductive layer may have antibacterial properties.

[0022] For example, the biocompatible conductive layer may comprise propylene glycol. The biocompatible conductive layer comprising propylene glycol may limit bacterial proliferation. The biocompatible conductive layer may comprise carboxymethylcellulose (CMC). The biocompatible conductive layer comprising carboxymethylcellulose (or CMC) may facilitate the absorption of wound exudates. Alternatively, or in combination, the biocompatible conductive layer may comprise hyaluronic acid. The presence of hyaluronic acid in the biocompatible conductive layer may stimulate cellular activity, in particular tissue regeneration, more specifically wound healing.

[0023] The electrode assembly comprises at least a working electrode, a reference electrode and a counter electrode. The electrode assembly may comprise more electrodes, in particular more than 3 electrodes. In addition, the dressing according to the invention may comprise several electrode assemblies, each of these electrode assemblies comprising at least a working electrode, a reference electrode and a counter electrode. Having several electrode assemblies makes it possible to increase the effective surface area for monitoring and improving the repair of a wound. Indeed, if a wound is large and extensive, it is then possible to apply a dressing that covers the entire wound while providing precise, targeted and effective monitoring andimprovement of wound repair, even locally. In the case of a dressing with several electrode assemblies, the biocompatible conductive layer covers each of the electrodes in each of the electrode assemblies.

[0024] The working electrode, reference electrode and counter electrode form an electrochemical sensor.

[0025] The electrochemical sensor makes it possible to monitor the concentration of a target analyte, for example oxygen, in the biocompatible conductive layer. The electrochemical sensor may be electrically associated with a processing unit via the at least one connection interface of the flexible substrate. In particular, the processing unit may contain a potentiostat. The potentiostat may establish and vary an electrical potential, or an electrical current in the electrochemical sensor. For example, an electrochemical method implemented by the processing unit may consist in applying and measuring either an electrical potential at the terminals of the electrodes or an electrical current flowing through the electrical circuit formed by the electrodes. Another electrochemical method may consist in measuring an electrical potential at the terminals of the electrodes, without applying any potential, current or voltage.

[0026] The working electrode is an electrode where, at its interface with the biocompatible conductive layer, an electrochemical reaction takes place, in particular a reaction involving a transfer of charges, more specifically an oxidation-reduction reaction. This electrochemical reaction occurs in combination and simultaneously with the electrochemical reaction occurring at the interface of the counter electrode and the biocompatible conductive layer.

[0027] The reference electrode has a known electrochemical potential that is constant over time. The potential of the reference electrode serves as a reference value and is used to calculate the electrochemical potential of the working electrode when measuring the voltage between the working electrode and the reference electrode. The potential of the reference electrode also serves as a reference for applying the electrochemical potential of the working electrode, particularly when measuring electric current. It is then possible to infer the concentration of the target analyte contained in the biocompatible conductive layer. In particular, the concentration of the target analyte contained in the biocompatible conductive layer may be obtained depending on the potential or the electric current.

[0028] The electrochemical sensor may be subjected to a variation in electrical potential or to an electric current. For example, a processing means may be arranged on the second surface of the flexible substrate and may be electrically associated with the dressing via the at least one connection interface of the dressing. The processing means may make it possible to generate a variation in the voltage or the electric current. In particular, a potentiostat may be used to vary the voltage or electric current. The potentiostat may also be used to collect electrical signalsfrom the electrochemical sensor. The response generated by the electrochemical sensor may be proportional to the concentration of the target analyte, such as a target chemical substance in the wound or exudate. The concentration may be determined by the processing means which collects the signals detected via the at least one connection interface of the dressing.

[0029] The counter electrode may be relatively distant from the working electrode. This avoids changes in the concentration of the target analyte and in the chemical environment around the working electrode. If the distance between the counter electrode and the working electrode is too small, interference, in particular chemical interference, may appear. If the distance between the counter electrode and the working electrode is too great, the diffusion of the species of interest may be limited, which may lead to malfunctioning of the electrochemical sensor, in particular a slower response time. A minimum distance between the counter electrode and the working electrode may preferably be between 1 millimetre and 5 millimetres.

[0030] The working electrode, the reference electrode and the counter electrode may have various shapes, in particular circular or rectangular. The working electrode, the reference electrode and the counter electrode may also be shaped as a portion of a ring.

[0031] ln one embodiment, the dressing may include a single sensor, the sensor being an electrochemical sensor, in particular an electrochemical sensor formed by the working electrode, the reference electrode and the counter electrode. The dressing may be devoid of optical or physical detection means, which simplifies its design and reduces its manufacturing costs.

[0032] l n one embodiment of the invention, the working electrode may have the shape of a disc. The reference electrode may have an annular shape or an arc shape. The counter electrode may have an annular shape or an arc shape. The reference electrode and the counter electrode may each have an arc shape, with these arcs being arranged so as to form an annular shape. The working electrode, in particular when in the form of a disc, may be positioned in the centre of this annular shape.

[0033] This geometry and arrangement of the electrodes allows for good diffusion of the species of interest, in particular analytes and biomolecules, between the electrodes, in particular between the working electrode, the reference electrode and the counter electrode. In addition, this arrangement of the electrodes allows a good distribution of the potential.

[0034] The counter electrode serves in particular electrically, and in particular electrochemically, compensate for the reaction taking place at the working electrode. It is possible to define a surface area ratio between the surface areas of the two electrodes. This surface area ratio corresponds to the ratio of the surface area of the counter electrode to the surface area of the working electrode. A surface area ratio strictly greater than 1 , in other words, a surface area of the counter electrode greater than that of the working electrode, allows a good distribution of thepotential. In addition, the higher this surface area ratio, the more stable the electrical potential or current measurements. In particular, the higher this surface area ratio, the lower the polarisation of the counter electrode, which improves the accuracy and stability of the measurements. In particular, the surface area ratio between the counter electrode and the working electrode may be at least 10. A surface area ratio of between 3 and 10 may also be preferred. In particular, a surface area ratio of between 3 and 10 makes it possible to benefit from the advantages mentioned above while reducing the quantities of raw materials required and therefore the manufacturing costs.

[0035] ln another embodiment of the invention, the working electrode may have a rectangular shape, in particular a square shape. The reference electrode may have a rectangular shape. The counter electrode may have a shape including at least one right angle. In particular, the counter electrode may partially surround the working electrode. The reference electrode and the counter electrode may each be formed with at least one right angle and be arranged so as to form a rectangle surrounding the working electrode. In particular, the counter electrode may have a surface area at least three times greater than the surface area of the working electrode.

[0036] Each of the electrodes of the electrode assembly may be directly arranged on the same surface of the flexible substrate. In one embodiment of the first aspect of the invention, each of the electrodes of the electrode assembly may be electrodeposited on the first surface of the flexible substrate.

[0037] Having each of the electrodes of the electrode assembly electrodeposited on the first surface of the flexible substrate allows for easier manufacture of the dressing. This therefore makes it possible to reduce manufacturing time and costs. In particular, this avoids the need for an additional layer, in particular a printed circuit board. The electrodes may be directly arranged on the flexible substrate.

[0038] An electroplating process makes it possible to accurately control the thickness and shape of the deposited electrodes.

[0039] l n one embodiment of the first aspect of the invention, at least the working electrode, the reference electrode and the counter electrode of the electrode assembly may be co-planar. Coplanarity makes it possible to manufacture the electrodes in a single step on the flexible substrate. This simplifies the production process, particularly for techniques such as electroplating. Coplanarity simplifies the electrical connection between the electrodes and the connection interface, in particular connected by metal bolts. The co-planar arrangement of the electrodes can make it possible to reduce the bulkiness of the dressing.

[0040] ln one embodiment of the invention where the dressing comprises multiple electrode assemblies, at least the working electrode, the reference electrode and the counter electrode ofeach electrode assembly may be co-planar. It is also possible that at least one of the electrode assemblies does not have a co-planar working electrode, reference electrode and counter electrode.

[0041] ln one embodiment of the first aspect of the invention, the dressing may comprise an edge that may extend from the first surface of the flexible substrate. And, the biocompatible conductive layer may be at least partially surrounded by the edge.

[0042] The edge acts as a structural element that improves the stability of the biocompatible conductive layer. The edge may extend perpendicularly from the first surface of the flexible substrate.

[0043] ln one embodiment of the invention, the edge may be discontinuous. The edge may comprise a number of portions. This makes it possible, in particular, to reduce the quantity of material used while improving the structural stability of the biocompatible conductive layer.

[0044] ln one embodiment of the first aspect of the invention, the edge may form a continuous contour surrounding the biocompatible conductive layer. In particular, the edge may completely surround the biocompatible conductive layer. Specifically, the edge may have a circular, elliptical or rectangular shape.

[0045] An edge forming a continuous contour surrounding the biocompatible conductive layer further enhances the structural stability of the biocompatible conductive layer. This also allows the user to more easily apply the dressing correctly and precisely to the wound or area of interest. An edge with a circular, elliptical or rectangular shape also improves the effectiveness of the dressing by adapting it to the different shapes that different wounds may have.

[0046] ln one embodiment of the first aspect of the invention, the edge may have a height equal to or greater than a height of the biocompatible conductive layer, in particular a maximum height of the biocompatible conductive layer. In particular, the edge may have a height in a direction orthogonal to the plane formed by the first surface of the flexible substrate that is equal to or greater than a height of the biocompatible conductive layer in this same direction orthogonal to the first surface.

[0047] This difference in height allows points of contact between the edge and the application area, in particular with the skin or the wound. In addition, this difference allows the biocompatible conductive layer to be retained and held inside the contour formed by the edge in the event of external overpressure being exerted on the dressing. In particular, in the case of overpressure in the direction orthogonal to the first surface of the flexible substrate.

[0048] l n one embodiment of the first aspect of the invention, the edge may be made of foam, in particular silicone foam or polyethylene foam.

[0049] A foam edge, in particular made of silicone or polyethylene, makes the dressing lighter. This also reduces manufacturing costs. Indeed, these materials are readily available and relativelyinexpensive. The edge may also be made of any other biocompatible material suitable for delineating and holding the biocompatible conductive layer in place.

[0050] ln one embodiment of the first aspect of the invention, the flexible substrate may comprise an adhesive region capable of adhering to the skin or a wound.

[0051] ln particular, the adhesive region may be on the first surface of the flexible substrate. More particularly, the adhesive region may be arranged on a surface that is separate and different from the surface on which the biocompatible conductive layer is arranged. The flexible substrate may also comprise several adhesive regions. This adhesive region allows the dressing to adhere more firmly to the patient's skin. This therefore improves the conditions of use of the dressing. In particular, the dressing can thus be applied to surfaces of the body with a high degree of curvature, such as a finger.

[0052] l n one embodiment of the first aspect of the invention, the second surface of the flexible substrate may have three separate connection interfaces each associated with an electrode. In particular, the connection interfaces may have a circular or rectangular shape.

[0053] ln particular, each of the three connection interfaces may be electrically connected and associated respectively with a working electrode, a reference electrode and a counter electrode.

[0054] ln one embodiment of the first aspect of the invention, the flexible substrate may comprise or may be made of: polymer, polyethylene, polypropylene, polyamides, polyethylene terephthalate (PET), polyetheretherketone (PEEK), polyetherketone (PEK), or any combinations of these materials.

[0055] A flexible substrate comprising or made of polymer, polyethylene, polypropylene, polyamides, PET, PEEK, PEK, or any combination of these materials, makes it possible to reduce manufacturing costs. These materials are relatively inexpensive and readily available. A flexible substrate made from these materials can have a lower mass compared to rigid or metallic substrates.

[0056] The reduction in manufacturing costs is all the more significant as the dressing is intended in particular for single use.

[0057] ln one embodiment of the invention, the thickness of the flexible substrate may be between 200 micrometres and 500 micrometres, in particular having a thickness of less than 500 micrometres. Such a thickness of the flexible substrate allows the dressing to be both flexible enough for use on curved surfaces, and rigid enough to withstand and remain intact when subjected to stresses, such as impacts or twisting. Such a thickness also allows the dressing to be flexible enough to be produced using the “reel-to-reel” technique. The production of flexible substrates using the "reel-to-reel" technique consists of unwinding a flexible material from a first reel, processing it continuously, for example by coating, printing, deposition, or other means, andthen winding the flexible substrate thus obtained around a second reel. This method of producing flexible substrate is known to be fast and economical. Thus, manufacturing costs can be reduced.

[0058] The biocompatible conductive layer may have a thickness of between 500 micrometres and 3 millimetres, in particular less than 1 millimetre. The lower the thickness of the biocompatible conductive layer, the easier the chemical transfer between the wound and the electrodes.

[0059] ln one embodiment of the first aspect of the invention, the working electrode may be made of Platinum (Pt), gold (Au) or graphene. The reference electrode may be made of Ag / AgCL The counter electrode may be made of Platinum (Pt) or gold (Au).

[0060] l n particular, the working electrode, the reference electrode and the counter electrode may be simultaneously and respectively made of Pt, Ag / AgCI and Au. More broadly, the counter electrode may be made of a non-corrosive metal, for example graphite or titanium (Ti). The working electrode may in particular be made of an inert metal such as gold, Pt or inert carbon (vitreous carbon, boron-doped diamond, pyrolytic carbon, etc.). Electrodes made from the materials mentioned above make it possible to improve the performance of the electrochemical sensor. In fact, this improves the electrochemical reactions at the interfaces of the different electrodes. It also allows the electrochemical sensor to generate electrical signals that can be detected, in particular by a processing unit, and to determine a concentration of a target analyte in the biocompatible conductive layer.

[0061] l n one embodiment of the first aspect of the invention, a support layer may be arranged over at least the entirety of the second surface of the flexible substrate. In particular, the support layer may be made of fabric, polyurethane, or polyethylene.

[0062] This support layer may enhance the structural stability of the dressing. It may also improve the adhesion of the dressing to the application area, especially to the user's skin or a wound. Indeed, the support layer may have a greater total surface area than that of the flexible substrate. Thus, the regions of the support layer, where the flexible substrate is not arranged thereon, may comprise at least one adhesive region capable of adhering to the skin or a wound.

[0063] The at least one adhesive region may be made, for example, from polymers such as acrylate or can be silicone-based, which helps to prevent irritation.

[0064] The support layer may also have additional properties such as, for example, tightness, tear strength and / or flexibility. This improves the durability of the dressing.

[0065] ln one embodiment of the invention, the at least one connection interface may be connected to at least one other connection interface arranged on the support layer. In particular, this at least one other connection interface may be arranged on a surface of the support layer opposite to a surface of the support layer on which the flexible substrate is arranged. Thus, in oneembodiment of the invention, a processing unit may be electrically associated with the dressing via the connection interface arranged on the support layer. In particular, a processing unit may be electrically associated with the connection interface arranged on the surface of the support layer opposite to the surface of the support layer on which the flexible substrate is arranged. In addition, the support layer may comprise several connection interfaces, in particular three.

[0066] ln one embodiment of the first aspect of the invention, the biocompatible conductive layer may be doped with an active ingredient or an active substance having healing properties, in particular the biocompatible conductive layer may be doped with oxygen. This active ingredient or this active substance may be a molecule, an atom, an ion or a cation. In particular, this active ingredient or this active substance may be oxygen. The biocompatible conductive layer may be a gel doped with an active substance. In particular, the biocompatible conductive layer may be a hydrogel doped with an active substance. In addition, the biocompatible conductive layer may further comprise an acid, or an inorganic material, in particular a conductive polymer, more specifically polypyrrole or polyaniline for example.

[0067] ln particular, the active ingredient may be a biomolecule, more specifically an enzyme, aptamer, or antibody, in particular to target a specific analyte. The active ingredient may be one or more silver particles, in particular for their antibacterial properties. The active ingredient may also be activated charcoal, in particular to absorb odours and toxins from the wound. Any other species that improves wound healing mentioned above may also be an active ingredient.

[0068] As an example, a hydrogel containing lactate may be used to measure the acidity of a wound in a wound healing monitoring device.

[0069] A biocompatible conductive layer doped with an active ingredient or active substance makes it possible to improve wound repair and healing. This makes it possible to reduce the repair or healing time of the wound.

[0070] ln one embodiment of the first aspect of the invention, positioning or guide elements may be arranged on the second surface of the flexible substrate and are configured to facilitate the association of the connection interfaces of the flexible substrate with the housing.

[0071] ln one embodiment of the first aspect of the invention, the dressing comprises a support layer and positioning elements. The positioning elements may be arranged on the support layer. In particular, the positioning elements may be arranged on the surface of the support layer opposite to the surface of the support layer on which the flexible substrate is arranged.

[0072] A second aspect of the invention relates to an assembly. The assembly comprises a dressing according to one of the embodiments of the first aspect of the invention and a processing unit. The processing unit comprises at least one potentiostat. The processing unit is electricallycoupled to the electrode assembly via the at least one connection interface arranged on the second surface of the flexible substrate of the dressing.

[0073] ln particular, the processing unit makes it possible to ensure a constant electrical potential at least at the working electrode, the reference electrode and the counter electrode of the dressing, in particular with the potentiostat. The processing unit may also be configured to impose, monitor and measure an electric current in the electrochemical sensor, in particular in the electric circuits of the working electrode and of the counter electrode. Preferably, no electric current flows through the reference electrode. The processing unit may also be configured to collect electrical signals, in particular electric currents or potentials. These electrical signals come from the electrode assembly of the dressing, in particular from the working electrode, the reference electrode and the counter electrode of the dressing. The processing unit may also be configured to process these electrical signals, in particular to calculate a concentration of a target analyte, in particular the concentration of oxygen, contained in the biocompatible conductive layer. The processing unit may also be configured to store and transmit the collected electrical signals as well as the results of the processing of these signals.

[0074] The assembly comprising a dressing according to one of the embodiments of the first aspect of the invention and a processing unit makes it possible to detect and measure electrical signals generated by an electrochemical reaction at the electrochemical sensor. The assembly also makes it possible, from these electrical signals, to determine the concentration of a target analyte contained in the biocompatible conductive layer.

[0075] ln one embodiment of the second aspect of the assembly, the processing unit may be configured to transmit detected electrical signals and the results of the processing of these signals via a wireless connection, in particular via a Bluetooth® connection. This embodiment of the invention facilitates the transmission and communication of the signals collected by the processing unit and the results of the processing of these signals.

[0076] ln one embodiment of the assembly, the processing unit may be contained in a housing. The housing may comprise a display screen. The display screen may be touch-sensitive and may allow a user to interact with the screen by means of touch presses. The housing containing the processing unit may be used and reused with different dressings by being successively connected and then disconnected from the connection interface of each dressing.

[0077] A third aspect of the invention relates to a method for manufacturing a dressing, in particular a dressing in accordance with one of the embodiments of the first aspect of the invention. The manufacturing method comprises the steps of: providing a flexible substrate, in particular the provided flexible substrate may comprise a first surface and a second surface opposite to the first surface. The method also comprises a step for forming, in particular by electroplating, anelectrode assembly on a first surface of the flexible substrate. The electrode assembly comprises at least a working electrode, a reference electrode and a counter electrode. And, the method also comprises a step for forming at least one connection interface on a second surface of the flexible substrate, opposite to the first surface. The method also comprises a step for electrically connecting each of the electrodes of the electrode assembly to the at least one connection interface. In particular, the at least one connection interface may be arranged on the second surface of the flexible substrate. And, the at least one connection interface may be configured to be electrically associated with a processing unit. The method further comprises a step for providing a biocompatible conductive layer and, a step for arranging the biocompatible conductive layer on the first surface of the flexible substrate. The biocompatible conductive layer covers at least the electrode assembly.

[0078] This manufacturing method makes it possible to produce a dressing in a relatively simple and inexpensive manner.In accordance with one embodiment, the electrode assembly may be formed directly on the flexible substrate, in particular directly on the first surface of the flexible substrate. This embodiment further simplifies the manufacturing method.

[0079] The dressing thus obtained has all the technical effects and advantages associated with one of the embodiments described in the first aspect of the invention.

[0080] The drawings accompanying the invention are incorporated into and form an integral part of the description to illustrate several embodiments of the present invention. These drawings, together with the description, serve to explain the principles of the invention. The sole purpose of the drawings is to illustrate the preferred and alternative examples of how the invention may be embodied and used, and should not be construed as limiting the invention solely to the embodiments illustrated and described. In addition, several aspects of the embodiments may individually or in various combinations, represent solutions in accordance with the present invention. The embodiments described below can therefore be considered alone or in any combination.

[0081] 0ther features and advantages will become apparent from the more precise description that follows of the various embodiments of the invention, as illustrated in the accompanying drawings, in which similar references refer to similar elements, and where:

[0082] FIG. 1 is a schematic representation of a cross-section, orthogonal to the plane formed by the flexible substrate, of the dressing according to a first embodiment of the first aspect of the invention.

[0083] FIG. 2 is a schematic representation of a top view of the dressing, from the wound side, in accordance with a second embodiment of the first aspect of the invention.

[0084] The invention will be described in more detail below, by using advantageous embodiments, as an example, and by reference to the drawings. The embodiments described are merely possible configurations, so that the individual features as described may be provided independently from one another, or may be omitted during when implementing the present invention.

[0085] Figure 1 shows a dressing 100 according to a first embodiment of the first aspect of the invention. The dressing 100 comprises a flexible substrate 3. The flexible substrate 3 has a first surface 5, and a second surface 7, opposite to the first surface 5. The dressing 100 also comprises an electrode assembly 9. The electrode assembly 9 comprises a working electrode 11 , a reference electrode 13 and a counter electrode 15.

[0086] The dressing comprises a biocompatible conductive layer 17, with a first surface 19. In particular, the first surface 19 is intended to be placed in contact with the wound. The first surface 19 may allow the dressing 100 to adhere to the wound or skin. The biocompatible conductive layer 17 may comprise at least one electrolyte. The biocompatible conductive layer 17 may comprise at least one analyte and / or be capable of transporting an analyte. The biocompatible conductive layer 17 may comprise at least one biomolecule or other additive.

[0087] Each of the electrodes 11 , 13, 15 of the electrode assembly 9 is arranged on the first surface 5 of the flexible substrate 3. And each of the electrodes 11 , 13, 15 of the electrode assembly 9 is respectively electrically connected to three connection interfaces 33, 31 , 29 by means of electrical connections 34, 32, 30. The electrical connection means 34, 32, 30 are arranged on the second surface 7 of the flexible substrate 3.

[0088] The electrical connection means 34, 32, 30 may be produced using metallised through holes that electrically connect the first surface 5 of the substrate and the second surface 7 of the substrate. Alternatively, it is possible to use Pogo (registered trademark) pins to produce the electrical connection means 34, 32, 30.

[0089] The working electrode 11 , the reference electrode 13 and the counter electrode 15 are co-planar in the dressing 100. In an alternative embodiment of the invention, the working electrode 11 , the reference electrode 13 and the counter electrode 15 may not be aligned, and, may not be coplanar.

[0090] The biocompatible conductive layer 17 is arranged on the first surface 5 of the flexible substrate 3 and covers at least the electrode assembly 9. Indeed, the electrode assembly 9 has a height H3 in the direction of an axis R and the biocompatible conductive layer 17 has a height H2 in this same direction and this same axis R. The axis R corresponds to the normal of the first surface 5 of the flexible substrate 3. The height H2 is greater than the height H3. The height H3 in the dressing 100 is the same for the three electrodes 11 , 13, 15. However, in alternative embodiments of the invention, the heights of each of the electrodes may differ from one another.

[0091] The working electrode, the reference electrode, and the counter electrode are configured to electrochemically interact with the biocompatible conductive layer 17 that completely encapsulates the electrode assembly 9.

[0092] A response generated by electrochemical reaction can be detected by means of the electrode assembly 9 and makes it possible to determine a concentration of the at least one analyte contained in the biocompatible conductive layer 17.

[0093] ln addition, the dressing 100 comprises an edge 23 having a height H1 in the direction of the axis R. In particular, the height H1 is greater than the height H2 of the biocompatible conductive layer. This makes it possible to structurally maintain the biocompatible conductive layer 17. The edge 23 also prevents the biocompatible conductive layer from extending beyond the contour delineated by the edge 23.

[0094] l n Figure 1 , the dressing 100 includes an edge 23 that completely encircles the biocompatible conductive layer.

[0095] The dressing 100 also comprises a support layer 21 with a first surface 25 and a second surface 27. The flexible substrate 3 is arranged on the support layer 21. In particular, the second surface 7 of the flexible substrate 3 is in direct physical contact with the first surface 25 of the support layer 21.

[0096] The flexible substrate 3 can be bonded and arranged on the support layer 21 by means of an adhesive region arranged at the interface of the flexible substrate 3 and the support layer 21. This adhesive region may be arranged only partially at the interface of the flexible substrate 3 and the support layer 21. In addition, this adhesive region may not be continuous.

[0097] For example, the layers 3 and 21 may be assembled by a layer lamination method.

[0098] The connection interfaces 29, 31 , 33 may be extended through the support layer 21 by means of electrical connections which are not shown in Figure 1 . These connection means may then be linked to other connection interfaces, in this case to 3 connection interfaces in the dressing 100. These three other connection interfaces may in particular be arranged on the second surface 27 of the support layer 21 .

[0099] Thus, a processing unit may be electrically associated with the dressing 100 by being arranged in direct physical contact with either, the interfaces 29, 31 , 33 of the flexible substrate 3, or, if there are any, with the other connection interfaces arranged on the second surface 27 of the support layer 21 .

[0100] Figure 2 schematically illustrates a dressing 200 in accordance with a second embodiment of the first aspect of the invention from the viewpoint on the wound side, above the dressing 200.

[0101] The dressing 200 differs from the dressing 100 of Figure 1 in that the support layer 21 comprises two adhesive regions 35, 37 intended to improve the adhesion of the dressing 200 to the wound or to the skin. These adhesive regions 35, 37 can also be arranged on the flexible substrate 3.

[0102] ln the example of Figure 2, the reference electrode 13 and the counter electrode 15 are shaped as a portion of a ring and arranged along a circular circumference 39. And, the working electrode 11 is circular in shape and arranged at the centre of the circular circumference 39.

[0103] The distance between the reference electrode 13 and the working electrode 11 is defined so as to be sufficient to prevent the reference electrode 13 from being disturbed by electrolytic or electric currents. One function of the reference electrode 13 is to accurately measure the potential of the system formed by the electrodes 11 , 13, 15.

[0104] The edge 23 of the dressing 200 is essentially rectangular. The edge 23 is arranged in a rectangle, in particular a rectangle with rounded corners. The edge 23 may be arranged at different locations on the first surface 5. Similarly, the biocompatible conductive layer 17 and the electrode assembly 9 may be arranged at different locations on the first surface 5. Similarly, the flexible substrate 3 may be arranged at different locations on the first surface 25 of the support layer 21.

[0105] ln alternative embodiments, the edge may surround a plurality of electrode assemblies.

[0106] ln other embodiments, there may be an edge for each of the electrode assemblies of the dressing.

[0107] The dressing 100 of figure 1 and the dressing 200 of figure 2 can be respectively manufactured by a manufacturing method which comprises the steps of: providing the flexible substrate 3; forming, in particular by electroplating, the assembly 9 of electrodes 11 , 13, 15 on the first surface 5 of the flexible substrate 3; forming at least one connection interface 29, 31 , 33 on the second surface 7 of the flexible substrate 3; electrically connecting each of the electrodes 11, 13, 15 to the at least one connection interface 29, 31 , 33 and providing the biocompatible conductive layer 17 and arranging it on the first surface 5 of the flexible substrate 3, the biocompatible conductive layer 17 covering at least the electrodes 11 , 13, 15.

[0108] List of reference signs 3: flexible substrate5: first surface of the flexible substrate 7: second surface of the flexible substrate 9: electrode assembly 11 : working electrode 13: reference electrode 15: counter electrode17: biocompatible conductive layer19: first surface of the biocompatible conductive layer21 : support layer23: edge25: first surface of the support layer27: second surface of the support layer29: connection interface30: electrical connection means31 : connection interface32: electrical connection means33: connection interface34: electrical connection means35: adhesive region37: adhesive region39: circular circumference100: dressing200: dressingH1 : height of the edgeH2: height of the biocompatible conductive layerH3: height of the electrode assemblyR: axis

Claims

CLAIMS1 . A dressing (100, 200) for a wound and for electrochemical detection of at least one analyte, the dressing (100) comprising: a biocompatible conductive layer (17), the biocompatible conductive layer (17) being intended to be placed in contact with a wound, and a flexible substrate (3) having a first surface (5) and a second surface (7) opposite to the first surface (5), and an electrode assembly (9), the electrode assembly (9) comprising at least a working electrode (11), a reference electrode (13) and a counter electrode (15), and each of the electrodes (11 , 13, 15) of the electrode assembly (9) is arranged on the first surface (5) of the flexible substrate (3), and each of the electrodes (11 , 13, 15) of the electrode assembly (9) is respectively electrically connected to at least one connection interface (29, 31 , 33) arranged on the second surface (7) of the flexible substrate (3), and the biocompatible conductive layer (17) is arranged on the first surface (5) of the flexible substrate (3) and covers at least the electrode assembly (9), and the biocompatible conductive layer (17) is configured to allow an electrochemical interaction between at least one analyte and the electrode assembly (9), a concentration of said analyte being determinable from a response generated by this electrochemical interaction.

2. The dressing (100, 200) according to claim 1 , wherein each of the electrodes (11 , 13, 15) of the electrode assembly (9) is electrodeposited on the first surface (5) of the flexible substrate (3).

3. The dressing (100, 200) according to claim 1 or 2, wherein at least the working electrode (11), the reference electrode (13) and the counter electrode (15) of the electrode assembly (9) are co-planar.

4. The dressing (100, 200) according to any one of the preceding claims, further comprising an edge (23) which extends from the first surface (5) of the flexible substrate (3), and the biocompatible conductive layer (17) is at least partially surrounded by the edge (23).

5. The dressing (100, 200) according to claim 4, wherein the edge (23) forms a continuous contour surrounding the biocompatible conductive layer (17).

6. The dressing (100, 200) according to claim 4 or 5, wherein the edge (23) has a height (H 1 ) equal to or greater than a height (H2) of the biocompatible conductive layer (17).

7. The dressing (100, 200) according to any of claims 4 to 6, wherein the edge (23) is made from foam, in particular silicone foam or polythelene foam.

8. The dressing (100, 200) according to any one of the preceding claims, wherein the flexible substrate (3) comprises an adhesive region (35, 37) capable of adhering to the skin or a wound.

9. The dressing (100, 200) according to any one of the preceding claims, wherein the second surface (7) of the flexible substrate (3) has three distinct connection interfaces (29, 31 , 33), each respectively associated with an electrode (11 , 13, 15).

10. The dressing (100, 200) according to any one of the preceding claims, wherein the flexible substrate (3) comprises or is made of: polymer, polyethylene, polypropylene, polyamides, polyethylene terephthalate, polyetheretherketone, polyetherketone or any combinations of these materials.

11. The dressing (100, 200) according to any one of the preceding claims, wherein the working electrode (11 ) is made of platinum, gold or graphene; the reference electrode (13) is made of Ag / AgCI and the counter electrode (15) is made of platinum or gold.

12. The dressing (100, 200) according to any one of the preceding claims, wherein a support layer (21 ) is arranged on at least the entirety of the second surface (7) of the flexible substrate (3), in particular the support layer (21) is made of fabric, polyurethane or polyethylene.

13. The dressing (100, 200) according to any one of the preceding claims, wherein the biocompatible conductive layer (17) may be doped with an active ingredient or an active substance having healing properties.

14. An assembly of the dressing (100, 200) according to any one of the preceding claims and of a processing unit, the processing unit comprising at least one potentiostat, and the processing unit is electrically coupled to the electrode assembly (9) via the at least one connection interface (29, 31 , 33) arranged on the second surface (7) of the flexible substrate (3) of the dressing (100, 200).

15. A method for manufacturing a dressing, in particular a dressing (100, 200) according to any one of claims 1 to 13, the manufacturing method comprising the steps of: providing a flexible substrate (3), forming, in particular by electroplating, an electrode assembly (9) on a first surface (5) of the flexible substrate (3), the electrode assembly (9) comprising at least a working electrode (11), a reference electrode (13) and a counter electrode (15), and forming at least one connection interface (29, 31 , 33) on a second surface (7) of the flexible substrate (3), opposite the first surface (5), electrically connecting each of the electrodes (11, 13, 15) of the electrode assembly (9) to the at least one connection interface (29, 31 , 33), and providing a biocompatible conductive layer (17) and arranging it on the first surface (5) of the flexible substrate (3), the biocompatible conductive layer (17) covering at least the electrode assembly (9).

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