Electrochemical sensor

Abstract

The invention relates to an electrochemical sensor (10) having at least three elements (18, 20, 22, 24, 28) selected from a group of elements, the electrochemical sensor (10) comprising a transducer element (20) and a membrane element (22) having selectivity for at least one target substance, the membrane element (22) is in direct contact with a further element (18, 20, 24, 28) of the electrochemical sensor (10) selected from the group of elements and is bonded together at the interface between them by a covalent chemical bond, and wherein the membrane element (22) comprises at least one membrane element (22), at least two elements (18, 20, 24, 28) selected from the group of elements other than the membrane element (22) are in direct contact and bonded together at the interface between them by a covalent chemical bond.

Description

Technical Field

[0001] This invention relates to an electrochemical sensor. Background Technology

[0002] Common electrochemical sensors, such as ion-selective electrodes, include membrane elements that are selective for at least one target substance and transducer elements that convert the presence of the target substance (also known as an analyte) into an electrical signal, particularly converting the concentration into a potential or current.

[0003] Such electrochemical sensors can be applied to many different purposes, such as detecting ions, molecules, proteins, bacteria, enzymes or other substances, for clinical, biopharmaceutical or similar applications.

[0004] However, the lifespan of these sensors is typically limited. In particular, the function of the sensors deteriorates over time due to delamination and / or water buildup at the sensor element interfaces. Summary of the Invention

[0005] The purpose of this invention is to provide an electrochemical sensor with improved lifespan and durability.

[0006] The objective of this invention is achieved through an electrochemical sensor having at least three elements selected from a group comprising a conductor element, a transducer element, a membrane element, a hydrophilic element, a housing, and a substrate. The electrochemical sensor includes a transducer element that converts the presence of at least one target substance into an electrical signal and a membrane element selective for the target substance. The membrane element and another element of the electrochemical sensor, selected from this group of elements, are in direct contact and covalently bonded together at their interface. Furthermore, at least two elements from this group of elements, excluding the membrane element, are in direct contact and covalently bonded together at their interface.

[0007] This invention is based on the understanding that covalent chemical bonds can improve the contact and adhesion between layers of various components, particularly in electrochemical sensors. In other words, these layers can be grafted together to improve the robustness of electrochemical sensors. It has been found that, in addition to lifetime, the temperature resistance of electrochemical sensors is significantly improved when not only the ion-selective membrane but also other components of the electrochemical sensor are bonded together by covalent chemical bonds. Furthermore, the signal and / or charge transport characteristics between individual components can be improved through interfacial bonding.

[0008] It should be clear that the statement "two elements are covalently bonded together at their interface" means that the two elements covalently bonded together are covalently bonded to each other over the entire region defined by the interface between them or only over a portion of the region defined by the interface.

[0009] The transducer element converts the presence of at least one target substance into an electrical signal; that is, the transducer element is configured to convert the presence of at least one target substance into an electrical signal. For example, the transducer element may be configured to convert the concentration of at least one target substance into an electric potential or an electric current.

[0010] Electrochemical sensors may also include conductive elements.

[0011] In one variant, the electrochemical sensor includes a conductive element that is in direct contact with a transducer element and is covalently bonded at the interface between the two elements, i.e., at the interface between the conductive element and the transducer element. Specifically, the conductive element or ion-electron transducer element can be a conductive or semi-conductive material. Materials such as metals or metalloids and their derivatives (e.g., in oxidized or halogenated forms) or materials intrinsically doped with chemical elements to affect their conductivity can be used, such as platinum (Pt), gold (Au), carbon (C), indium tin oxide (ITO), silver / silver chloride (Ag / AgCl), tantalum oxide (Ta₂O₅), and iridium oxide (IrO₂). x Electrodes in n-type or p-type silicon. Ion-electron transducer elements can also comprise structures such as nanoscale assemblies of monomolecules or polymers that are inherently electronically conductive or semi-conductive. It can include organic conductive polymers and their copolymers, such as polyacetylene (PAC), poly(p-phenyleneacetylene) (PPV), polypyrrole (PPY), polyaniline (PANI), polyphenylene sulfide (PPS), polythiophene (PT), their respective derivatives and / or mixtures, such as poly(3,4-ethylenedioxythiophene)polystyrene sulfonate (PEDOT:PSS). Transducer elements and conductor elements are examples of two elements besides membrane elements that can be bonded together to increase the overall stability and lifetime of the sensor.

[0012] Alternatively or additionally, the conductor element may be in direct contact with the membrane element and bonded by covalent chemical bonds at the interface between the two elements.

[0013] The transducer element and conductor element can also be made of the same material, such as conductive platinum or carbon-based material. This facilitates sensor manufacturing because the transducer element and conductor element can be manufactured in a single processing step.

[0014] It is also conceivable that the electrochemical sensor includes an insulating substrate, wherein a conductive element, a transducer element, and / or a selective membrane element partially covers the substrate. In the region of the substrate not covered by the conductive element, the substrate is in direct contact with another element and is covalently bonded to the other element at the interface between the substrate and the directly contacting element, the other element being particularly a membrane element, a transducer element, or a hydrophilic element.

[0015] The substrate serves as a support for the electrochemical sensor. Covalent bonds between the substrate and other contact elements further enhance the sensor's mechanical stability and lifespan.

[0016] Additionally, the substrate can serve as an electrical insulator. It can be composed of inorganic materials, such as ceramic or glass materials (e.g., quartz, mica, porcelain, SiO2, Al2O3, AlN, Si3N4) or composite materials, such as printed circuit board materials (e.g., FR-4) made of glass fiber and epoxy resin plastic. These materials exhibit various interesting combinations of chemical inertness, robustness, and / or excellent electrical insulation properties, thereby preventing unwanted interference with the detection signal.

[0017] In an advantageous variation, the conductor element and / or transducer element comprises structured, particularly randomly or specifically organized, electronically conductive or semiconducting materials. Materials of any compound, such as aggregated dendritic or self-assembled crystalline particles, nanotubes, sheets, flakes, cubes, rods, wires, or specific morphologies with high specific surface areas (e.g., porous or nanoflower shapes), can be applied. Of course, the materials mentioned above, composite materials, or mixtures are also possible.

[0018] By applying structured materials, the contact interface with other components can be increased. Furthermore, charge transport and electrical properties can be improved.

[0019] In another preferred embodiment, the conductor element is composed of a solid electronically conductive material having a functionalized, particularly silanized, interface to adjacent elements. The conductor element and / or transducer element can be a solid planar contact, for example, made of graphite, graphene, doped or glassy carbon (C), gold (Au), platinum (Pt), copper (Cu), or silver (Ag). Functionalization, particularly silanization, is technically easy to implement and can and / or improve the formation of covalent bonds between the conductor element and the direct contact layer.

[0020] Optionally, each element of the electrochemical sensor, particularly the layer, is in direct contact with at least one other element of the electrochemical sensor and is covalently bonded to the other element at the interface between the directly contacting elements. This configuration provides the sensor with the highest thermal and mechanical stability.

[0021] In another embodiment, the membrane element comprises a polymer matrix. The polymer matrix can be an insulating, hydrophobic, and / or repeating structure based on the same monomer or a mixture of different monomers and comonomers. Materials constituting the polymer matrix and based on organic hydrophobic polymers can be applied, such as epoxy resins, polyethylene, polystyrene, poly(vinyl chloride), polysiloxanes, polyesters, polyurethanes, poly([meth]acrylate), polyethers, or fluorocarbon polymers and derivatives. It may also contain crosslinking agents, plasticizers, detergents, or several of these to accommodate membrane stiffness and control the transport of target substances.

[0022] Alternatively, monomers and comonomers may have alkyl groups (e.g., derivatives of acrylates or methacrylates) to replace the use of plasticizers.

[0023] It is also conceivable that at least some of the alkyl groups can be replaced by other functionalized groups containing halogen elements or atoms, such as chlorides or fluorides. This improves the hydrophobicity of the membrane element and prevents water permeation and accumulation at the interface.

[0024] In another embodiment, the membrane element includes a polymer matrix and at least one chemical selector, particularly an ion carrier for recognizing the target substance, and / or at least one neutral carrier, to improve the transport characteristics of the target substance through the selective membrane element. This improves the selectivity of the sensor for the target substance.

[0025] To avoid the consumption of membrane components, at least one of the selector and / or neutral support may be covalently bonded to the polymer matrix.

[0026] In a technically simple arrangement, the polymer matrix is ​​made of polymerized monomers and polymerized comonomers, wherein the polymerized comonomers or a portion thereof are selectants.

[0027] It is also conceivable that the electrochemical sensor includes a hydrophilic element located between the transducer element and the membrane element. The hydrophilic element can be in direct contact with the transducer element and bonded by covalent chemical bonds at the interface between the two elements (i.e., the interface between the hydrophilic element and the transducer element), and / or the hydrophilic element can be in direct contact with the membrane element and bonded by covalent chemical bonds at the interface between the two elements (i.e., the interface between the hydrophilic element and the membrane element).

[0028] The hydrophilic element may include at least: a hydrophilic polymer matrix (e.g., a hydrogel) capable of interacting favorably with a polar solvent to result in solubility or swelling capacity; and an internal electrolyte comprising a polar solvent (e.g., water), a soluble salt (e.g., KCl, NaCl) for increasing conductivity, an interfering salt acting as a potentiating ion, a known amount of a target substance, a free chemical dopant (e.g., one or both forms of a redox pair), a chelating agent (e.g., ethylenediaminetetraacetic acid, EDTA), and / or a chemical substance for buffering the internal pH, or several of these. Materials constituting a hydrophilic polymer matrix and based on organic hydrophilic polymers can be applied, such as materials derived from natural compounds, such as polysaccharides (e.g., dextran, alginate, chitosan, agarose, and pullulan) and / or proteins (e.g., albumin, gelatin, collagen, lectins, lentinan, and pea globulin); and / or materials derived from synthetic compounds, such as polyacrylamide, poly([alkyl]acrylic acid), poly([[meth]acrylate), poly(ethylene glycol), poly(ethylene oxide), poly(styrene sulfonic acid), poly(vinylamide), poly(ethyleneamine), poly(vinylazine), poly(N-vinylimidazolium), poly(vinylpyridine), poly(ethyleneimine), poly(L-histidine), poly(methyl vinyl ether), poly(oxymethylene), poly(L-proline), polyfuran, or poly(vinyl alcohol), their respective derivatives, and / or mixtures thereof.

[0029] Typically, a hydrophilic layer can be applied to achieve a fixed concentration of the target substance and / or interfering agent at the transducer and / or membrane interface. Therefore, it can improve the sensor's sensitivity, detection limit, and / or selectivity.

[0030] In another embodiment, the transducer element includes chemical groups and / or contains chemical substances, particularly crosslinking agents, which form covalent chemical bonds at the interface to directly contact adjacent elements. These chemical bonds can be formed with membrane elements, conductor elements, or both. This reduces the risk of lamination separation and water buildup at the interface.

[0031] It can also be envisioned that chemical groups and / or chemical substances form covalent bonds within the transducer element. This improves the thermal and chemical stability of the transducer element and prevents potential consumption of components.

[0032] In another variation, the transducer element may comprise a conductive polymer, particularly a conductive polymer with chemical dopants (e.g., electroactive materials and / or redox materials). The dopants may, for example, improve the conductivity of the transducer element and / or increase sensor sensitivity or response time to changes in the concentration of the target substance.

[0033] In another preferred embodiment, the transducer element and / or hydrophilic element includes a chelating agent. By applying a chelating agent (e.g., EDTA), the amount of target substance at the layer and / or layer interface can be immobilized. This particularly improves the sensor's detection limit.

[0034] Furthermore, it is conceivable that electrochemical sensors include a substrate composed of an insulating material having a functionalized, particularly silanized, interface to adjacent elements. Surface modification of the material imparts physical, chemical, and / or biological properties different from those of the initial material surface. For example, the process of functionalizing the substrate results in the formation of a monolayer that acts as a coupling agent between the substrate and adjacent elements, thereby improving their adhesion at the interface. Functionalization includes adding small functional groups, portions, oligomers, and / or polymers to the surface or interface, particularly through oxidation or grafting processes such as plasma, flame, or corona treatment. The functionalized addition portion can be an integrated portion of at least one of the adjacent element components or for bonding to at least one of the adjacent element components, for example, through further chemical reactions, such as copolymers serving as adjacent polymer matrices. Functionalization provides a simple yet highly effective method for achieving covalent chemical bonds between the substrate and adjacent elements.

[0035] In another variation, the substrate is partially covered by the aforementioned conductor elements and / or transducer elements. To facilitate the fabrication process of the electrochemical sensor, the substrate, conductor elements, and / or transducer elements can be functionalized together in a single processing step. Attached Figure Description

[0036] Further advantages and features will become apparent from the following description and accompanying drawings of the invention, in which non-limiting exemplary embodiments of the invention are illustrated:

[0037] - Figure 1 A cross-sectional side view of a first embodiment of the electrochemical sensor according to the present invention is schematically shown;

[0038] - Figure 2 A cross-sectional side view of a second embodiment of the electrochemical sensor according to the present invention is schematically shown;

[0039] - Figure 3 A cross-sectional side view of a third embodiment of the electrochemical sensor according to the present invention is schematically shown;

[0040] - Figure 4 A cross-sectional side view of a fourth embodiment of the electrochemical sensor according to the present invention is schematically shown;

[0041] - Figure 5A cross-sectional side view of the layers and two grafting interfaces of the electrochemical sensor according to the present invention is schematically shown.

[0042] - Figure 6 A schematic cross-sectional side view of the layers and three grafting interfaces of the electrochemical sensor according to the present invention is shown; and

[0043] - Figure 7 A schematic cross-sectional side view of the layers and three grafting interfaces of the electrochemical sensor according to the present invention, as well as the grafting selector and neutral support, is shown. Detailed Implementation

[0044] Figure 1 A first embodiment of the electrochemical sensor 10 according to the present invention is illustrated schematically.

[0045] Sensor 10 is located in liquid sample 12 and is connected to reference electrode 14 (e.g., Ag / AgCl / 3M KCl) via electrical measuring device 16 (e.g., potentiometer).

[0046] The sensor 10 includes a conductor element 18, a transducer element 20, and a selective membrane element 22.

[0047] In the described embodiment, the conductor element 18 is a solid contact, for example, made of glassy carbon.

[0048] The transducer element 20 is a PEDOT:PSS thin layer covering the conductor element 18.

[0049] The selective membrane element 22 is composed of a polymer, for example, made of polyvinyl chloride (PVC), and other chemicals, and covers the transducer element 20. It is selective for at least one target substance, such as calcium ions.

[0050] In this context, selectivity means that the affinity of membrane element 22 for the target substance is better than its affinity for other substances (e.g., interfering substances and / or water) due to polymeric properties (e.g., hydrophobicity) and / or the bonding efficiency from selectivity and carrier. In short, the mass transfer of substances other than the analyte is hindered during the transfer / exchange process across membrane element 22 and across interfaces (e.g., between membrane element 22 and liquid sample 12).

[0051] In the described embodiment, the conductor element 18 is in direct contact with the transducer element 20 and is bonded together at their interface by covalent chemical bonds. Furthermore, the transducer element 20 is in direct contact with the selective membrane element 22 and is bonded together at their interface by covalent chemical bonds. These direct chemical bonds make the sensor 10 very durable and robust at high applied temperatures.

[0052] The sensor 10 shown operates as follows: a membrane element 22 selectively transports the target substance from the liquid sample 12 toward the transducer element 20. Optionally, the membrane element 22 can be filled with the target substance before measurement to reduce sensor setup. A concentration gradient of the target substance is generated between the corresponding interfaces of the liquid sample 12-membrane element 22 and the membrane element 22-transducer element 20. The transducer element 20 converts information about the presence of the analyte (e.g., its concentration) into an electrical signal, specifically a potential or current, generated, for example, by the target substance discharging through the transducer element 20. A conductor element 18 conducts the electrical signal to an electrical measuring device 16 that detects the signal. By evaluating the detected signal, information about the interface gradient can be obtained, thereby obtaining information about the target substance in the liquid sample 12. For example, according to the Nikolsky-Eisenman semi-empirical model, the potential difference between the sensor 10 and the reference electrode 14, measured by the electrical device 16, such as a potentiometer, is proportional to the concentration of the target substance in the liquid sample 12.

[0053] The given examples of functional principles and materials do not, of course, limit the scope of the invention. Other types of conductor elements 18, such as conductive elements made of copper, graphite, graphene, or doped carbon, and / or transducer elements 20, such as those made of Pt nanoflowers or iridium oxide (IrO) produced by electrodeposition, can be applied. x Transducer elements made of bonded nanoparticles or redox conductive polymers based on electropolymerized or chemically polymerized PANI derivatives, and / or other types of membrane elements 22, such as membrane elements made of polyurethane acrylate-based compositions polymerized under UV.

[0054] For example, conductor element 18 and / or transducer element 20 may include structured, random or specifically organized conductive or semiconducting materials to achieve increased interfacial surface area contact and / or improved charge transport or charge transfer characteristics toward adjacent layers.

[0055] The following reference Figures 5 to 7 Describe further details about the individual components, their parts, and their interfaces.

[0056] Figure 2 A second embodiment of the electrochemical sensor 10 according to the present invention is illustrated schematically.

[0057] The second embodiment corresponds to the first embodiment in several basic features; therefore, only the differences will be discussed below. Components that are identical or functionally identical are given the same reference numerals.

[0058] Compared to the first embodiment, the sensor 10 according to the second embodiment includes an additional hydrophilic element 24 located between the membrane element 22 and the transducer element 20.

[0059] The hydrophilic element 24 includes a hydrophilic layer, particularly a hydrogel swollen with an electrolyte, which improves the detection limit and / or selectivity of the sensor 10 by fixing the analyte concentration at the transducer interface.

[0060] Apart from the additional hydrophilic element 24, the functional principle is the same as described above.

[0061] exist Figure 2 In this process, the hydrophilic element 24 is in direct contact with the transducer element 20 and is bonded to the transducer element 20 by covalent chemical bonds at the interface between them.

[0062] In addition, the hydrophilic element 24 is in direct contact with the membrane element 22 and is bonded to the membrane element 22 by covalent chemical bonds at the interface between them.

[0063] In the second embodiment, the conductor element 18, the transducer element 20, and the membrane element 22 are located within a housing 26, which has an opening sealed by the selective membrane element 22. The housing 26 and the selective membrane element 22 protect the hydrophilic element 24 from the influence of the liquid sample 12.

[0064] Optionally, the housing 26 is in direct contact with the selective membrane element 22 and / or the hydrophilic element 24 and is covalently bonded to the selective membrane element 22 and / or the hydrophilic element 24 at their interface. This direct chemical bonding prevents the individual elements from peeling off from the housing 26, even under elevated applied temperature and pressure variations of the sensor 10.

[0065] Figure 3 A third embodiment of the electrochemical sensor 10 according to the present invention is illustrated schematically.

[0066] The third embodiment corresponds to the first embodiment in several basic features; therefore, only the differences will be discussed below. Components that are identical or functionally identical are provided with the same reference numerals.

[0067] Compared to the first embodiment, the sensor 10 according to the third embodiment includes a substrate 28. In this embodiment, the substrate 28 is a common electronically and chemically inert ceramic plate, such as a thin Si / SiO2 wafer substrate.

[0068] The conductor element 18 is a conventionally deposited metal layer that partially covers the substrate 28, such as a titanium-platinum (Ti / Pt) electrode locally deposited by electron beam evaporation under nanofabrication methods, such as photolithography and vacuum processes.

[0069] Alternatively, the substrate 28 and / or conductor element 18 may be functionalized, particularly silanized.

[0070] exist Figure 3In this process, both substrate 28 and conductor element 18 are silanized (during the fabrication of sensor 10, the silanization step is performed after the deposition of conductor element 18) to add functional groups on both surfaces for covalent bonding with at least one of the selective membrane 22 and / or transducer element 20 components.

[0071] Due to silanization, the sensor 10 shown includes a connection interface with direct chemical bonds between the substrate 28 and the membrane element 22, and between the conductor element 18 and the transducer element 20.

[0072] In the first region 30 of the substrate 28 that is not covered by the conductor element 18 or the transducer element 20, the substrate 28 is in direct contact with the membrane element 22 and is bonded to the membrane element 22 by covalent chemical bonds at the interface between them.

[0073] Additionally, in the second region 32 of the substrate 28 that is not covered by the conductor element 18, the substrate 28 is in direct contact with the transducer element 20 and is covalently bonded to the transducer element 20 at the interface between them.

[0074] In this embodiment, direct chemical bonding prevents the individual components from peeling off from the substrate 28, even under elevated application temperatures and extended application times of the sensor 10.

[0075] Figure 4 A fourth embodiment of the electrochemical sensor 10 according to the present invention is illustrated schematically.

[0076] The fourth embodiment is a combination of the second and third embodiments. Components with the same corresponding features and functions are also provided with the same reference numerals.

[0077] Compared to the first embodiment, the sensor 10 includes a substrate 28 and a hydrophilic element 24.

[0078] In the fourth embodiment, each element of the electrochemical sensor 10 is in direct contact with at least one other element and is bonded to the at least one other element by covalent chemical bonds at the interface between them.

[0079] Figure 4 The sensor 10 shown includes interfaces with covalent chemical bonds between a substrate 28 and a membrane element 22 in a first region 30, between a substrate 28 and a transducer element 20 in a second region 32, and between a substrate 28 and a hydrophilic element 24 in a third region 34.

[0080] It also includes interfaces with covalent chemical bonds between the conductor element 18 and the transducer element 20, between the transducer element 20 and the hydrophilic element 24, and between the hydrophilic element 24 and the selective membrane element 22.

[0081] The described embodiments are by no means limiting the scope of the invention. Similar sensors 10 with fewer or even more chemically bonded interfaces are possible.

[0082] In the following text, based on Figures 5 to 7 The various elements and interfaces of the electrochemical sensor 10 according to the present invention are described in more detail below.

[0083] Figure 5 A schematic side view of a cross-section of the electrochemical sensor 10 is shown. It is conceivable that it is based on the first and / or third embodiments (…). Figure 1 Electrochemical sensor 10 (and / or 3).

[0084] The sensor 10 includes a conductor element 18, a transducer element 20, and a selective membrane element 22.

[0085] The direct contact interface between conductor element 18, transducer element 20, and selective membrane element 22 is grafted (bonded together by covalent chemical bonds). This is in Figure 5 The number 36 is represented by a vertical stripe pattern.

[0086] In this embodiment, the transducer element 20 includes a conductive polymer 38 having chemical dopants (e.g., PEDOT:PSS).

[0087] The transducer element 20 also includes chemical coupling groups and / or coupling agent chemicals 40, particularly crosslinking agents, which form covalent chemical bonds at the interface for direct contact with adjacent elements. Furthermore, the chemical coupling groups and / or coupling agent chemicals 40 form covalent chemical bonds within the transducer element 20, resulting in increased stability and reduced delamination and / or water buildup at the interface.

[0088] In addition, the membrane element 22 includes at least one polymer matrix 42 and at least one chemical selector 44, particularly an ion carrier selective for the target substance, and / or at least one neutral carrier 46, for improving the transport properties of the target substance through the selective membrane element 22.

[0089] Figure 6 Another side view of the cross-section of the electrochemical sensor 10 is schematically shown. It corresponds in several basic features to... Figure 5 The side view is shown, therefore only the differences will be discussed below. Identical and functionally identical parts are given the same reference numerals.

[0090] and Figure 5 Compared to sensor 10, Figure 6 The sensor 10 has an additional hydrophilic element 24 located between the transducer element 20 and the selective membrane element 22.

[0091] It can be imagined that, Figure 6 The second and / or fourth embodiments are shown. Figure 2 The cross section of the electrochemical sensor 10 (and / or 4).

[0092] As indicated by the vertical stripe pattern 36, the direct contact interfaces between the conductor element 18, transducer element 20, hydrophilic element 24, and selective membrane element 22 are all grafted. This makes the sensor 10 very durable.

[0093] In the described embodiment, the electrolyte contained in the hydrophilic element 24 includes, in addition to a small amount of the target substance, a chelating agent 48 (e.g., EDTA) to improve the performance of the sensor 10, particularly the lower detection limit.

[0094] Of course, the transducer element 20 may also optionally include a chelating agent 48 and / or a crosslinking agent.

[0095] Figure 7 Another side view of the cross-section of the electrochemical sensor 10 is schematically shown. It corresponds in several basic features to... Figure 6 Side view. Similarly, only the differences will be discussed below. Identical and functionally identical parts are provided with the same reference numerals.

[0096] and Figure 6 Compared to sensor 10, Figure 7 The sensor 10 has a selective membrane element 22, in which the selectant 44 and / or neutral support 46 are grafted (covalently bonded) to a polymer matrix 42 to avoid consumption. This is in Figure 7 The middle is indicated by the spring-shaped tail 50 connected to the corresponding material.

[0097] In this embodiment, the polymer matrix 42 is made of polymerized monomers and polymerized comonomers. A portion of the polymerized comonomer or polymerized comonomer is a selector 44 and / or a neutral carrier 46.

Claims

1. An electrochemical sensor having at least three elements (18, 20, 22, 24, 26, 28), said at least three elements (18, 20, 22, 24, 26, 28) being selected from a group of elements including a conductor element (18), a transducer element (20), a membrane element (22), a hydrophilic element (24), a housing (26), and a substrate (28). The electrochemical sensor (10) includes a transducer element (20) that converts the presence of at least one target substance into an electrical signal and a membrane element (22) that is selective for the at least one target substance. in, The membrane element (22) is in direct contact with another element (18, 20, 24, 26, 28) of the electrochemical sensor (10) selected from the group of elements, and is covalently bonded together at the interface between them. Among them, at least two elements (18, 20, 24, 26, 28) selected from the group of elements, other than the membrane element (22), are in direct contact and are bonded together by covalent chemical bonds at the interface between them.

2. The electrochemical sensor according to claim 1, comprising the conductor element (18), wherein, The conductor element (18) is in direct contact with the transducer element (20) and is covalently bonded to the transducer element (20) at the interface between the two elements (18, 20), and / or wherein the conductor element (18) is in direct contact with the membrane element (22) and is covalently bonded to the membrane element (22) at the interface between the two elements (18, 22).

3. The electrochemical sensor according to claim 2, comprising the substrate (28), wherein, The conductor element (18) partially covers the substrate (28), and wherein, in the region (30, 32, 34) of the substrate (28) not covered by the conductor element (18), the substrate (28) is in direct contact with another element (20, 22, 24) selected from the group of elements and is covalently bonded to the other element (20, 22, 24) at the interface between the substrate (28) and the directly contacting element (18, 20, 22, 24, 28), the other element (20, 22, 24) selected from the group of elements being particularly the membrane element (22) or the transducer element (20) or the hydrophilic element (24).

4. The electrochemical sensor according to claim 3, wherein, The substrate (28) is composed of inorganic materials.

5. The electrochemical sensor according to any one of claims 2 to 4, wherein, The conductor element (18) and / or the transducer element (20) comprise structured, particularly randomly or specifically organized, electronically conductive materials.

6. The electrochemical sensor according to any one of claims 2 to 5, wherein, The conductor element (18) is composed of a solid electronically conductive material having a functionalized, particularly silanized interface to adjacent elements (20, 22, 24).

7. The electrochemical sensor according to any one of the preceding claims, comprising the hydrophilic element (24), the hydrophilic element (24) being located between the transducer element (20) and the membrane element (22), wherein, The hydrophilic element (24) is in direct contact with the transducer element (20) and is covalently bonded to the transducer element (20) at the interface between the two elements (20, 24), and / or the hydrophilic element (24) is in direct contact with the membrane element (22) and is covalently bonded to the membrane element (22) at the interface between the two elements (22, 24).

8. The electrochemical sensor according to any one of the preceding claims, wherein, Each element (18, 20, 22, 24, 26, 28) of the electrochemical sensor (10) is in direct contact with at least one other element (18, 20, 22, 24, 26, 28) selected from the set of elements of the electrochemical sensor (10) and is covalently bonded to the at least one other element (18, 20, 22, 24, 26, 28) at the interface between the directly contacting elements (18, 20, 22, 24, 26, 28).

9. The electrochemical sensor according to any one of the preceding claims, wherein, The membrane element (22) comprises: a polymer matrix (42) and at least one chemical selector (44), particularly an ion carrier selective for the target substance, and / or at least one neutral carrier (46), for improving the transport properties of the target substance through the selective membrane element (22).

10. The electrochemical sensor according to claim 9, wherein, At least one of the selector (44) and / or the neutral carrier (46) is covalently bonded to the polymer matrix (42).

11. The electrochemical sensor according to claim 9 or 10, wherein, The polymer matrix (42) is made of polymerized monomers and polymerized comonomers, wherein the polymerized comonomers or a portion thereof are the selector (44).

12. The electrochemical sensor according to any one of the preceding claims, wherein, The transducer element (20) includes chemical groups and / or contains chemical substances (40), particularly crosslinking agents, which form covalent chemical bonds at the interface to directly contact adjacent elements (18, 22, 24, 26, 28).

13. The electrochemical sensor according to claim 12, wherein, The chemical groups and / or chemical substances (40) form covalent chemical bonds within the transducer element (20).

14. The electrochemical sensor according to any one of the preceding claims, wherein, The transducer element (20) comprises a conductive polymer (38), particularly a conductive polymer with chemical dopants.

15. The electrochemical sensor according to any one of the preceding claims, wherein, The transducer element (20) and / or the hydrophilic element (24) include a chelating agent (48).

16. The electrochemical sensor according to any one of the preceding claims, comprising the substrate (28) comprising an insulating material having a functionalized, particularly silanized interface to adjacent elements (18, 20, 22, 24).

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