DE102017117478A1 - Sensor material with temperature-dependent coloring - Google Patents

Abstract

The present invention provides a sensor material comprising a solid support material, an indicator dye, and a reaction substance wherein the indicator dye and the reaction substance are bound to the support material and a reactive group of the reaction substance can interact with the indicator dye to change temperature of an optical property of the indicator dye ,

Description

Field of the invention

The present invention relates to a sensor material for detecting temperature changes by a color change. In particular, the invention relates to a sensor material comprising a solid support material, an indicator dye and a reaction substance, wherein a reactive group of the reaction substance with the indicator dye can interact with temperature changing a optical property of the indicator dye.

State of the art

Thermochromic materials are known in the art. For example, they are based on liquid crystalline materials (Experiments in Fluids, 2001, 30: 190; Polym. Eng. Sei, 30: 1005-1018), the physico-structural changes of which result in a change in reflection. Another example is colorless leuco dyes ( JP 06106848 A . JP 07179040 A ), which become colored by the action of acids as a function of the temperature.

Furthermore, there are spyran dyes ( AU 2011240892 B2 ), which undergo an internal molecular cyclization reaction with themselves, resulting in colorlessness or colorlessness.

Also, polydiacetylenes are reported to exhibit a color change depending on their physical structure (Chem. Sci., 2014, 5, 4189).

Problems to be solved by the invention

However, the prior art does not disclose the use of temperature-dependent indicators incorporated in a solid support.

Therefore, it is the object of the present invention to provide a sensor material wherein the indicator dye is in or on a solid support and wherein a visible color change can be effectively achieved by raising the temperature in the range of room temperature to 150 ° C.

Summary of the invention

The object has been achieved by providing a sensor material according to the present claims.

1. [1] Sensormaterial, das ein festes Trägermaterial, einen Indikatorfarbstoff und eine Reaktionssubstanz umfasst, worin der Indikatorfarbstoff und die Reaktionssubstanz an das Trägermaterial gebunden sind und eine reaktive Gruppe der Reaktionssubstanz mit dem Indikatorfarbstoff unter Änderung einer optischen Eigenschaft des Indikatorfarbstoffes temperaturabhängig wechselwirken kann.
2. [2] Sensormaterial nach [1], wobei die Wechselwirkung reversibel ist.
3. [3] Sensormaterial nach [1] oder [2], wobei die Wechselwirkung eine kovalente oder nicht-kovalente Wechselwirkung ist.
4. [4] Sensormaterial nach einem der vorstehenden Punkte, wobei mindestens ein Mitglied der Gruppe, die aus dem Indikatorfarbstoff, der Reaktionssubstanz und der reaktiven Gruppe besteht, über einen Abstandshalter an das Trägermaterial gebunden ist.
5. [5] Sensormaterial nach einem der vorstehenden Punkte, wobei mindestens ein Mitglied der Gruppe, die aus dem Indikatorfarbstoff, der Reaktionssubstanz und der reaktiven Gruppe besteht, über Abstandshalter unterschiedlicher Länge an das Trägermaterial gebunden ist.
6. [6] Sensormaterial nach einem der vorstehenden Punkte, wobei der Indikatorfarbstoff und/oder die Reaktionssubstanz kovalent an das Trägermaterial gebunden ist/sind.
7. [7] Sensormaterial nach einem der vorstehenden Punkte, wobei die eine reaktive Gruppe tragende Reaktionssubstanz das Trägermaterial ist.
8. [8] Sensormaterial nach einem der vorstehenden Punkte, wobei das Trägermaterial ein organisches Polymermaterial, ein Papiermaterial, ein Textilmaterial, ein Wundverband oder ein Verpackungsmaterial ist.
9. [9] Sensormaterial nach einem der vorstehenden Punkte, wobei der Indikatorfarbstoff ein Azofarbstoff, Cyaninfarbstoff, Merocyaninfarbstoff, Oxonolfarbstoff, Triphenylmethanfarbstoff, Trifluoracetylazofarbstoff, Trifluoracetylfarbstoff, Aldehydfarbstoff oder Boronsäurefarbstoff ist.
10. [10] Sensormaterial nach einem der vorstehenden Punkte, wobei die reaktive Gruppe der Reaktionssubstanz eine Amingruppe, Hydroxygruppe oder Thiolgruppe ist.
11. [11] Sensormaterial nach einem der vorstehenden Punkte, wobei der Indikatorfarbstoff ein Azofarbstoff ist und reaktive Gruppe ein Amin eines aminhaltigen Polymers, ausgewählt unter Amino-PVC, Aminoethylcellulose und Polyethylenimin, ist oder der Indikatorfarbstoff ein Trifluoracetylfarbstoff ist und reaktive Gruppe eine Hydroxygruppe oder Thiolgruppe ist.
12. [12] Sensormaterial nach einem der vorstehenden Punkte, wobei der Indikatorfarbstoff ein Trifluoracetylazofarbstoff ist und die Reaktionssubstanz ein lipophiles Amin ist.
13. [13] Sensormaterial nach einem der vorstehenden Punkte, wobei die optische Eigenschaft eine für das menschliche Auge sichtbare Färbung ist.
14. [14] Sensormaterial nach einem der vorstehenden Punkte, wobei die Wechselwirkung zwischen Indikatorfarbstoff und Reaktionssubstanz unter Änderung einer optischen Eigenschaft in einem Bereich von vorzugsweise 0°C bis 80°C temperaturabhängig ist.
15. [15] Sensormaterial nach einem der vorstehenden Punkte, das eine Indikatorfolie ist.

The object of the present invention is defined in particular in the following items [1] to [15]:

1. [1] A sensor material comprising a solid support material, an indicator dye and a reaction substance, wherein the indicator dye and the reaction substance are bonded to the support material and a reactive group of the reaction substance can interact with the indicator dye to change temperature of an optical property of the indicator dye.
2. [2] Sensor material according to [1], whereby the interaction is reversible.
3. [3] Sensor material according to [1] or [2], where the interaction is a covalent or non-covalent interaction.
4. [4] The sensor material according to any preceding item, wherein at least one member of the group consisting of the indicator dye, the reaction substance and the reactive group is bonded to the carrier material through a spacer.
5. [5] The sensor material according to any preceding item, wherein at least one member of the group consisting of the indicator dye, the reaction substance and the reactive group is bonded to the carrier material through spacers of different lengths.
6. [6] The sensor material according to any one of the preceding items, wherein the indicator dye and / or the reaction substance is / are covalently bound to the carrier material.
7. [7] The sensor material according to any one of the preceding items, wherein the reactive substance carrying a reactive group is the carrier material.
8. [8] The sensor material according to any preceding item, wherein the support material is an organic polymer material, a paper material, a textile material, a wound dressing or a packaging material.
9. [9] The sensor material according to any preceding item, wherein the indicator dye is an azo dye, cyanine dye, merocyanine dye, oxonol dye, triphenylmethane dye, trifluoroacetylazo dye, trifluoroacetyl dye, aldehyde dye or boronic acid dye.
10. [10] The sensor material according to any preceding item, wherein the reactive group of the reaction substance is an amine group, hydroxy group or thiol group.
11. [11] The sensor material according to any preceding item, wherein the indicator dye is an azo dye and reactive group is an amine of an amine-containing polymer selected from amino-PVC, aminoethylcellulose and polyethyleneimine, or the indicator dye is a trifluoroacetyl dye and reactive group is a hydroxy group or thiol group ,
12. [12] A sensor material according to any preceding item, wherein the indicator dye is a trifluoroacetylazo dye and the reaction substance is a lipophilic amine.
13. [13] Sensor material according to any of the preceding items, wherein the optical property is a color visible to the human eye.
14. [14] The sensor material according to any preceding item, wherein the interaction between the indicator dye and the reaction substance is temperature-dependent by changing an optical property in a range of preferably from 0 ° C to 80 ° C.
15. [15] Sensor material according to any one of the preceding points, which is an indicator film.

Advantages of the invention

The inventive approach allows a novel determination of the temperature change with a chemically stable system that can be connected not only physically but also covalently to polymeric support materials. Thus, it is much more stable than on liquid crystalline materials or leuco dyes or spiropyrane based systems, since they can be dissolved by solvents or destroyed by (for example textile) washing processes. Furthermore, the newly developed measurement principle results in a significantly wider temperature range with an observable color change than with existing temperature indicators based on leuco dyes and liquid crystalline materials.

Embodiments of the invention

Interaction of the indicator dye with the reaction substance

The indicator dye and the reaction substance interact. This interaction can be described as chemical equilibrium, which depends on various factors, eg. B. of the concentration of the educts, but also of the temperature according to the principle of Le Chatelier-Braun. Thereafter, a chemical equilibrium always shifts so that it evades the external constraint in the form of a change in temperature or pressure. In an exothermic reaction, heat is released, i. the standard reaction enthalpy is negative. When such a reaction mixture in equilibrium is heated, the quantities of the products are reduced, those of the starting materials increase. In this case, heat is consumed, whereby the system avoids the external constraint in the form of temperature increase. Accordingly, the yield increases in equilibrium for an endothermic reaction with temperature increase.

The temperature dependence of the interaction reaction between the indicator dye and the reaction substance as starting materials can be controlled by selecting the reactants and the other parameters of the reaction so that an exothermic or endothermic interaction reaction takes place as required.

For example, the equilibrium between the starting materials and the product can basically be shifted by increasing the concentration of the educts. In addition, the formation of the product is facilitated if the educts carry hydrophobic residues and the medium is hydrophilic. The same applies if the starting materials are hydrophilic or even charged and the medium is hydrophobic.

The equilibrium may also be influenced by the polarity of the environment of indicator dye and reaction substance, i. whether the chemical environment, for example a polymer matrix, is highly polar or strongly non-polar.

The equilibrium can furthermore be influenced by shifting the carrier molecules to which dye molecules and reaction substances are bonded to one another and / or by altering the mobility of the carrier material and thus changing the number of possible bonds between dye molecules and reaction substances.

Since all these equilibria are also temperature dependent, the parameters can be adjusted as needed so that a change in temperature causes a suitable shift of the equilibrium and thus the optical property of the system.

temperature dependence

The temperature dependence of the coloration of the indicator dye is based on the temperature dependence of the interaction between the indicator dye and the reaction substance. This temperature dependence is according to the invention in the range of -20 ° C to 150 ° C, preferably from 0 ° C to 80 ° C and more preferably from 20 ° C to 80 ° C.

reversibility

The term "reversible" as used herein in reference to the interaction between indicator dye and reaction substance means that the change in color associated with this interaction is reversible. This means that a change in color caused by temperature change is reversed on return to the starting temperature and the coloration is restored before the temperature changes.

This reversibility is preferably given over a plurality of temperature change cycles.

binding

The binding between indicator dye and reaction substance may be covalent or noncovalent.

A covalent bond can be made directly or via spacers.

As used herein, the term "noncovalent" bonding or interaction refers to an ionic, a coordinative, a hydrophobic, a hydrophilic, or a van der Waals or hydrogen bonding based interaction.

Indicator dye and reaction substance

As indicator dyes, indicator dyes having trifluoroacetyl groups for interaction with amines, alcohols, phenols, thiols and amino acids, indicator dyes having boronic acid groups for interaction with sugars and catecholamines and indicator dyes having aldehyde groups for interaction with amines, amino acids and organo-phosphates can be used.

Further examples of indicator dyes are a pyrylium salt or dyes which include a trifluoroacetyl group, a tricyanovinyl group, an aldehyde group, a maleimide group, a dicyanovinyl group, a hydrazine group, an amino or diamino group, an isothiocyanate or isocyanate group, or a boronic acid group.

An example of a suitable dye is the commercially available 4- (dioctylamino) -4 '- (trifluoroacetyl) azobenzene (Sigma-Aldrich), which is useful as an indicator dye for reaction with amines:

A preferred indicator dye is a trifluoroacetylazo dye.

In general, azo dyes are preferred. Azo dyes are characterized by the general formula R ¹ -N = NR ² . The two radicals (R ¹ and R ² , usually aromatic) may be identical or stand for different radicals. If the indicator dye molecule contains two azo groups, it is a diazo dye. Accordingly, there are also tri-, tetra- and polyazo dyes.

Typical of azo dyes is the azo group -N = N- with the coloring nitrogen double bond. These synthetic indicator dyes use amines as starting material, in the simplest case the aniline. Azo dyes reach their diversity by the simple substitution of the hydrogen atoms on the benzene ring or rings, which then auxochromize the azo bond and allow an exact adjustment of the color shades.

Azodyes often have polar and non-polar substituents and can thus be tailored to the required medium. With appropriate construction, they can also form hydrogen bonds in addition to van der Waals bonds.

This indicator dye group is represented in the entire color range due to the diverse coupling options with indicator dyes. Azo dyes are used for dyeing textiles, fats and oils, for dyeing waxes, straw, wood, and for paper.

An example of an azo dye is methyl red.

Methyl red is yellow in the neutral (left structure), so absorbs violet light. At a pH below 4.4, the molecule is protonated at the nitrogen, the polarized azo bridge leads to color deepening to red by absorption of now green (longer-wave) light (right structure).

The azo bridge may be in protonated or deprotonated form depending on the pH. This is associated with a shift in color depth. Azo dyes are therefore used as acid-base dyes. Examples include methyl red, methyl orange, Congo red and Alizaringelb R. In addition, there are also redox dyes among the azo dyes.

The indicator dyes preferably carry specific receptor groups to ensure selective reaction substance recognition.

An example of the detection of amines is the trifluoroacetyl group-amine interaction shown in the following figure, which leads to a color change from red to yellow

As receptors that cause a visible change in the control surface for reactive oxygen species, for example, metal-ligand complexes can be used and the recognition reaction then takes place at the metal center. Fluorescein sulfonate groups are selective receptor groups for hydrogen peroxide, maleimide functions are selective receptor groups for thiols, tricyanovinyl groups are selective receptor groups for primary and secondary amines, pyrylium functions are selective receptor groups for primary amines, hydrazine functions are selective receptor groups for aldehydes and ketones, amino groups are selective receptor groups for Aldehydes and ketones, boronic acid functions are selective receptor groups for diols, 1,2-diaminobenzene groups are selective receptor groups for nitrogen oxides, aldehyde functions are selective receptor groups for amino acids, isocyanates are selective receptor groups for alcohols, isothiocyanates are selective receptor groups for amines and alcohols. Crown ethers, calixarenes, and cryptands are selective receptor groups for cations and anions, while metal-polyphyrin complexes are selective receptor functions for carbon monoxide, amines, and nitrogen oxides.

The following compilation gives examples of UV-absorbing trifluoroacetylbenzene derivatives 1-8, liquid crystal ligands 9-10, stilbene reactants 11-12 and azobenzene reactants.

Examples of indicator dyes which can be used in the present invention are fluorophores bearing said receptors or receptor groups. Fluorophores can interact with reaction substances to change their optical properties. A distinction is made between fluorophores which non-covalently bind to reaction substances and those which can be covalently bound to reaction substances.

• F-X + HY-Molekül → F-Y-Molekül + XH.

The general reaction scheme in all known processes can be represented as follows: A fluorophore F contains a group X (receptor group) which reacts with a second group (eg HY) present on a reaction substance molecule ("molecule") (or even a strong non-covalent bond) is received. In the formation of chemical (covalent) bonds, a group of type XH can be cleaved, typically according to the following reaction equation:

• FX + HY molecule → FY molecule + XH.

However, the conjugation can also take place in the sense of an addition reaction to form the compound F-XH-Y molecule. Typical examples of the groups X and Y and the reaction types are as follows: X (on the fluorophore) Y (on the reaction substance molecule) Reaction type (leaving group or new group) -SO ₂ Cl R'-NH ₂ Substitution (-HCl) -CO-CH ₂ -I R'-SH Substitution (-HI) -CO-CH ₂ -Br R'-COOH Substitution (-HBr) -CO-O-NHS *) R'-NH ₂ Substitution (-N-hydroxysuccinimide) --NCS R'-NH ₂ Addition (-NH-CS-NH-R ') NCO R'-OH (alcohol) Addition (-NH-CO-OR ') -maleinimide R'-SH addition biotin R 'avidin Affinity binding (non-covalent) avidin R 'biotin Affinity binding (non-covalent) -Pyrylium R'-NH ₂ Substitution (-H ₂ O) boronic acid RAW Substitution (-H ₂ O) crown ether R'-NH ₃ ⁺ complex bond -Calixaren R'-NH ₃ ⁺ complex bond cryptand R'-NH ₃ ⁺ complex bond -COCF ₃ R'-NH ₂ addition CHO R'-NH ₂ addition - tricyanovinyl R'-NH ₂ substitution -Dicyanovinyl R'SH addition -NH ₂ Aldehyde / ketone addition -NH-NH ₂ Aldehyde / ketone addition - (NH ₂ ) ₂ Nitrogen oxides addition *) NHS = N-hydroxysuccinimide

In this way, it is possible to react a fluorophore F with a reaction substance and thus make it accessible to all fluorescence analytical methods.

The above fluorophore F can be replaced by any other indicator dye. That is, the receptor group X is not limited to binding to a fluorophore. Rather, it may be bound to any indicator dye employed in the present invention which changes its optical properties upon interaction with the reaction substance.

As described above, there are various ways of obtaining a molecule with an indicator dye, e.g. As a fluorescent marker to provide.

Known indicator dye groups for coupling with organic compounds are boronic acids RB (OH) ₂ . Boronic acids are derivatives of boric acid in which a hydroxy group is substituted by an organyl group R. The organyl group may contain at least one group selected from an acetonyl group, acyl group (eg, acetyl group, benzoyl group), alkyl group (eg, methyl group, ethyl group), alkenyl group (eg, vinyl group, allyl group), alkynyl group (propargyl group) , Aminocarbonyl group, aryl group (eg phenyl group, 1-naphthyl group, 2-naphthyl group, 2-thiophenyl group, 2,4-dinitrophenyl group), alkylaryl group (eg benzyl group, triphenylmethyl group), benzyloxycarbonyl group (Cbz), tert-butoxycarbonyl group ( Boc), carboxy group, (fluorene-9-ylmethoxy) carbonyl group (Fmoc), furfuryl group, glycidyl group, haloalkyl group (e.g., chloromethyl group, 2,2,2-trifluoroethyl group), indolyl group, nitrile group, nucleosidyl group and trityl group.

support material

The carrier material can be any material to which an indicator dye and a reaction substance can be bound.

The carrier material may be, for example, an organic polymer material, a paper material, a textile material, a wound dressing or a packaging material.

The carrier material may in particular be a textile material, for example a woven or nonwoven fabric. The fabric may consist of the usual textile materials, such as cotton, sheep's wool or the like, silk or synthetic fibers.

The sensor material may have the appearance of the carrier material. That is, the sensor material according to the invention may be, for example, an organic polymer material, a paper material, a textile material, a wound dressing or a packaging material.

Preferred polymers are amine-containing polymers (e.g., amino-PVC, aminoethylcellulose, polyethyleneimine) to which the indicator dye is attached or embedded. This is especially true when using a trifluoroacetylazo dye. In this case, in addition, a lipophilic amine may be present. Alternatively, an additional lipophilic amine is not present in this case.

Polymers can also be made by polymerizing an indicator dye having polymerizable chemical functions into a polymer. For example, when the indicator dye carries a vinyl, acryl, acrylamide, methacrylate group, it may be copolymerized into methacrylic acid, methyl methacrylate, hydroxyethyl methacrylate, styrene, acrylamide, methylenebisacrylamide, etc.

The indicator dye can also be coupled to the polymer via click chemistry or Suzuki, Heck or Sonogashira coupling.

In a preferred embodiment, the carrier material is a film of an organic polymer. Thus, the sensor material is an indicator film, in particular a film of an organic polymer.

Solid carrier material or solid sensor material

The term "solid" as used herein in reference to the carrier material or sensor material means that the material is a solid, ie, not liquid or gaseous, and accordingly is stable, in particular dimensionally stable, within the temperature ranges specified herein. The term "solid" also excludes emulsions or gels or the like.

On the other hand, a solid carrier material or a solid sensor material can also have a certain content of liquid medium, so that a reaction, in particular a reversible interaction, between indicator dye and reaction substance is made possible or facilitated.

The liquid medium may be an aqueous medium or an organic medium or a mixture thereof.

The medium is selected depending on the reactants.

For example, a solid support material or a solid sensor material may have some moisture content, water, e.g. in the range of 0.1 to 40%, 1 to 30%, 1 to 20%, 5 to 40%, 10 to 40% or 10 to 30% at room temperature.

For the interaction between indicator dye and reaction substance minimum moisture content in the carrier material or sensor material may be advantageous or essential, for. B. a moisture content of at least 0.1%, at least 1%, at least 5% or at least 10% at room temperature.

The same preferred levels apply to the use of organic media or solvents.

Interaction between indicator dye and reaction substance

The interaction between the indicator dye and the reaction substance is determined by several factors. Indicator dye and reaction substance react in a chemical reaction as starting materials and give the product. Whether an indicator dye and a reaction substance interact and thus cause a color change or not depends first on the concentration of the reactants and the accessibility of the starting materials in the composition according to the invention.

The temperature dependence of the interaction depends critically on the binding energy of the product. When the indicator dye and / or the reaction substance is covalently bound to the support material, the interaction also depends on the temperature-dependent movement of the support material molecules.

In one embodiment, the indicator dye is contained in a carrier material and moves from the carrier material to the reaction substance and / or the reaction substance moves toward the indicator dye fixed in the carrier material. That is, in a first alternative, that the indicator dye is contained in the carrier material but is not covalently or otherwise fixed. Rather, it is, for example, contained in a liquid and can be separated with this liquid from the carrier material or diffuse within the liquid or from the liquid. In a second alternative, the indicator dye is firmly fixed on or in the carrier material, so that preferably no bleeding or discharge of the indicator dye occurs. This fixation may be by covalent bonding, described by attachment to particles, or by inclusion in a compartment whose outer wall is not permeable to the indicator dye but to the reaction substance to be detected. A third alternative is a combination of the first two alternatives in that both the indicator dye and the reaction substance are free to move.

An example of a sensor material according to the invention comprises a trifluoroacetylazo dye and a lipophilic amine, wherein the indicator dye shows a color change from violet to orange upon reversible chemical reaction with the lipophilic amine.

The amine mentioned in the present invention may be a lipophilic amine. The term "lipophilic" amine means that an amine group is attached to a lipophilic chain, especially a hydrocarbon chain.

The term "lipophilic" chain is synonymous with "hydrophobic" chain and specifically refers to a hydrocarbon chain having at least 4 carbon atoms, preferably at least 6, at least 8 or at least 10 carbon atoms, preferably 4 to 30 carbon atoms, more preferably 6 to 24 carbon atoms, and even more preferably 8 to 22 carbon atoms. The hydrocarbon chain can be linear or branched, saturated or unsaturated.

Binding of the indicator dye and / or the reaction substance to the carrier material

As used herein, "the indicator dye and the reaction substance bound to the support material" means that the indicator dye and the reaction substance interact directly or indirectly with the support material to provide some adhesion to the support material, and thus bleeding or Washing out the indicator dye and the reaction substance is prevented or at least restricted or slowed down.

The expression "wherein the indicator dye and the reaction substance are bound to the carrier material" generally means that the indicator dye and the reaction substance interact with the carrier material, and in particular means that the indicator dye and the reaction substance are embedded in the carrier material and / or on the Surface of the carrier material are arranged.

The interaction of the indicator dye and the interaction of the reaction substance with the carrier material can be independent of each other.

But they can also be dependent on each other, for example, both are bound to the substrate via the same functionalization or the same spacer.

The embedding in the carrier material may in particular mean that a matrix of carrier material is present. This matrix can be a polymer matrix of the carrier material itself. The matrix may also be embedded in the carrier material as a gel matrix.

The interaction of the indicator dye and / or the reaction substance with the carrier material may be covalent or non-covalent. As used herein, the term "non-covalent" interaction refers to an ionic, a coordinative, a hydrophobic, a hydrophilic or a van der Waals forces or hydrogen bonds based interaction.

The binding takes place, for example, via nanoparticles and / or microparticles present in or on the carrier material, which are described in more detail below. In addition, the indicator dye may be bonded to the fibers in a textile or casting material.

According to one embodiment, the indicator dye and / or the reaction substance is / are bound to the carrier material. Both are preferably covalently bonded to the support material.

A stable chemical bonding of indicator dye and / or reaction substance to the carrier material, such as textile fibers or polymers, may, for. Example, be achieved by the use of amino-functionalized fibers and the chemical bonding of an acid function of the indicator dye to the amino groups of the fibers. The resulting amide bond is very stable and also ensures the permanent dyeing of the fibers with indicator dyes.

An advantage of materials whose fibers are provided with chemically bound indicator dyes and / or reaction substances is the ease of handling and the high information content of, for example, color change.

With regard to the location of the application of the bandage materials with fibers provided with chemically bound indicator dyes and / or reaction substances, there is an important advantage in the chemical bonding and thus very high stability of the dyeing. Due to the stable adhesion of the fibers no discharge of the indicator dyes and / or reaction substances.

The indicator dye may also be attached to or embedded in amine-containing polymers (e.g., amino-PVC, aminoethylcellulose, polyethyleneimine). Here, the amino group of the polymer itself can function as a reactive substance.

The reaction of trifluoroacetyl dyes occurs, albeit more slowly, also with polymers bearing hydroxyl or thiol groups. An example of such a polymer is polyHEMA.

Binding of the indicator dyes and / or reaction substances to particles

According to an alternative embodiment, the indicator dyes and / or the reaction substances can not be attached directly but indirectly by chemical bonding to the fibers, such as. By being covalently bonded to particles, which in turn are covalently or noncovalently bonded, printed, glued or laminated to the fibers of the substrate, or embedded in a polymer, or otherwise bonded to the substrate are.

The material of the particles may consist of inorganic components, for example of silicas, titania, silica, zirconium phosphate, zeolites, silica, gold, silver or glass, or of organic materials, preferably polymers, such as cellulose and cellulose derivatives, such as carboxymethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, dextran , Polyacrylamide, gelled starch, gelatin, polylactate, polystyrene or polyvinylpyrrolidone, or the aforementioned materials may be included as a component in these particles, or hybrid materials, such as organically modified sol-gel glasses, or up-conversion nanoparticles or magnetic nanoparticles.

The particles used in the present invention are nano- and / or microparticles and have, for example, an average diameter ranging from 10 nanometers to 100 microns, inclusive. The particles can be spherically shaped. In order to bind the indicator dyes and / or reaction substances chemically stable to particles, they can be covalently bonded to the surface or into pores of the particles, for example. Alternatively, it is possible for indicator dyes and / or reaction substances to be covalently copolymerized into the particles during their production. As a result, the particles can be coated in a separate production process with the indicator dye and / or the reaction substance, and then printed on the textiles in the usual printing process.

In embodiments, the indicator dye and / or the reaction substance can be easily handled and used in a variety of ways by being directly attached to the particles. For example, a simple application of the indicator dye and / or the reaction substance with the particles on or in the carrier material is possible. In the preparation of the indicator dye and / or the reaction substance with particles z. B. be present as a suspension and sprayed onto the substrate, printed or doctored. Furthermore, the suspension can be drawn as a film and the film can be applied to a carrier. Furthermore, the direct binding of the indicator dye and / or the reaction substances to the particles leads to a faster response compared to known systems through shorter diffusion paths.

The indicator dye and / or the reaction substance can be bonded directly to particles by means of a chemical bond. The chemical bond z. B. be an atomic bond or covalent bond. In the case of an atomic bond is a firm bond. Thereby, leakage of the indicator dye and / or the reaction substance from the area containing the particles can be avoided.

An interaction of the indicator dye with the reaction substance can be detected optically based, for example, on absorption, reflection, luminescence, SPR (SPR = Surface Plasmon Resonance) or IR (IR = infrared absorption or Raman absorption).

For this purpose, suitable reversible or irreversible indicator dyes can be used with appropriate receptor functionalities. These tailor-made indicator dyes are chemically stable (covalently bonded) to the particles of suitable organic or inorganic polymers. As already mentioned, the particles can then be processed either directly or embedded in a suitable natural or artificial polymer matrix to form a sensor.

The use of particles has the advantage over known systems of faster response through shorter diffusion paths. Due to the small dimensions of the particles, the z. B. in the range of 10 to 150 nm or in the range of 3 to 600 nm, results in a faster reaction of the embedded indicator dye on the reaction substance compared with the embedding thicker Polymermatrizes.

Furthermore, the particles may be porous. Thus, selectivities towards the biofilm constituents, and thus the reliability of the color change, can be influenced by the porosity of the particles. Here, depending on the porosity or type of pores, the diffusion of the reaction substance can be advantageously controlled, as for example with zeolites or MCM-41.

For particles, it is also possible to use several indicator dyes simultaneously, embedded in different particles. These can recognize several reaction substances in parallel. Alternatively, a plurality of indicator dyes having different reactivities with respect to the reaction substance may extend the temperature range of the signal change. Alternatively, in luminescence measurements, an inert indicator dye can be added to refer the signal. This further increases the reliability of the statement of the sensor.

Furthermore, the particles may have a core and a shell. In other words, the particles can be designed in a core-shell construction. In this case, the core of the particle may comprise the indicator dye and / or the reaction substance, and the shell of the particle control a solubility of the particle in polymer materials.

Alternatively, the shell of the particle may have pores, wherein the pores are selectively permeable to a gas, and wherein the core of the particle comprises the indicator dye, wherein the indicator dye is adapted to detect the gas in its ionic form. Thus, the shell may have a specific porosity which selectively passes only gases, while in the core there is an indicator dye for ions, which then detects the gas in its ionic form.

Above all, the use of the particles offers the possibility of a stable immobilization of the indicator dye and / or the reaction substance. The indicator dye and / or the reaction substance can be chemically stabilized (covalently) incorporated into the matrix of the particle-forming polymer. Thus, they can no longer escape from the particles. The particles may optionally be introduced into a polymer layer, crosslinked or applied directly to a support material, such as a film.

A major advantage of particles is thus their significantly improved processability over other formulations, as evidenced by their good processability in roll-to-roll processes, ink-jet printing, screen printing and extrusion. This is a big advantage on a favorable large-scale production of the sensor.

One particular embodiment of the present invention utilizing particles utilizes so-called localized surface plasmon resonance (LSPR) between metal nanoparticles (eg, gold and silver nanoparticles). One nanoparticle is functionalized with an amino group, and another nanoparticle is functionalized with a trifluoroacetyl group. Upon contact of the nanoparticles, a chemical reaction of the amino group with the trifluoroacetyl group occurs. This leads due to the LSPR in gold nanoparticles to a blue color. If the contact of the particles is dissolved at elevated temperature, a red coloration is observed.

spacer

As described in the present application, indicator dyes and / or reaction substances may be covalently bonded to the support material.

In each case, binding can be direct.

Alternatively, however, it is also possible to use a spacer (or "spacer") in order to covalently bond the components contained in the sensor material according to the invention.

This covalent bond relates to the bond between the carrier material and the indicator dye and / or between the carrier material and the reaction substance.

In a preferred embodiment, both the indicator dye and the reaction substance are bound to the carrier material via spacers. In this case, the spacer may be the same and have multiple functionalities, so that both the indicator dye and the reaction substance may be bound to the same spacer molecule.

In each embodiment, chemically different spacers and / or spacers of different lengths may be used.

Chemically different spacers are preferably used when both an indicator dye and a reaction substance are bonded to the support material, or when different indicator dyes or different reaction substances are bound to the support material.

The spacer preferably has an optionally interrupted by oxygen atoms and / or amino groups hydrocarbon chain having a chain length of preferably from 5 to 10,000 atoms. Preferably, this spacer via amino groups to the carrier material, for. B. polymer, attached; Alternatively, other coupling groups are possible which can be obtained by attaching suitable reactive groups to free carboxylic acid groups present on the polymer or the like. In particular, the spacer is obtained by reacting at least difunctional amines optionally of different length such as polyethylene glycol-NH ₂ and / or a polyalkyleneamine such as tetraethylene-pentamine with the carrier material and by reacting with the indicator dye or the reaction substance.

In this context, the terms "derived from polyalkylene glycol-NH ₂ ", "derived from polyethylene glycol-NH ₂ ", "derived from polyalkyleneamine" and "derived from tetraethylenepentamine" mean that a terminal modified with NH ₂ groups polyalkylene glycol / polyethylene glycol or an oligoalkyleneamine / tetraethylenepentamine has been reacted with the carrier material and with the indicator dye or the reaction substance, so that the resulting spacer has at least two coupling groups, the carrier material being bound via one of these groups and the indicator dye or the reaction substance via the other of these groups , The bond is usually designed in each case as -C (O) NH coupling group.

The spacer preferably comprises both spacers derived from polyethylene glycol-NH _{2 of} different lengths and spacers derived from tetraethylenepentamine.

The presence of a variable length surface spacer as described above, particularly of different lengths, increases the mobility of the attached group and thereby improves structural flexibility.

By using spacers of different lengths, the number of dye molecules or the reaction substance molecules per unit area or volume unit can be significantly increased, so that the performance of the sensor material can be improved.

Binding of the spacers to the carrier material

The following describes the bonding of the spacers to the substrate.

The same considerations apply equally to the binding of the spacers to the indicator dye and / or to the reaction substance.

The free amino end of the functionalization of the PEG-NH ₂ or TEPA is suitable for attachment to the support material. However, it is also possible to use a COOH radical as functionalization on the carrier material.

The combination of the use of carrier material and the described functionalization has the advantage that the spacer-functionalized carrier material, for example NH ₂ -PEG carrier material or TEPA carrier material, are used.

As already stated above, for the functionalization, for example, tetraethylenepentamine (TEPA) of the formula (1) H ₂ N-CH ₂ CH ₂ -NH-CH ₂ CH ₂ -NH-CH ₂ CH ₂ -NH-CH ₂ CH ₂ -NH ₂ (Formula (1)) be used. Commercially available TEPA is often a mixture of several compounds (oligomers), which are formed from a different monomer number and therefore have a different chain length. The TEPA used in the present compound may therefore contain, for example, one or more of the compounds selected from the group consisting of N- (2-aminoethyl) -N '- {2- {2-aminoethyl) amino} ethyl} - 1,2-ethanediamine; 4- (2-aminoethyl) -N- (2-aminoethyl) -N '- {2 - {(2-aminoethyl) amino} ethyl} -1,2-ethanediamine; 1- (2-aminoethyl) -4 - [(2-aminoethyl) amino] ethyl] piperazine) and 1- [2 - [[2 - [(2-aminoethyl) amino] ethyl] amino] ethyl] piperazine).

These compounds differ in their structure and thus their reactivity with the reactants.

Thus, the term "tetraethylene pentamine" or "TEPA" used herein includes not only the compound of the formula (1) but also any of the other compounds mentioned above alone or in a mixture of two or more of these compounds.

The polyethylene glycol-NH ₂ (PEG-NH ₂ ) is derived from polyethylene glycol (PEG). PEG is a polymer of ethylene glycol monomer units and can have a wide variety of chain lengths. Typical chain lengths of commercially available PEG include 200, 400, 600 or 1500 monomer units. In the present invention, the PEG-NH _{2 may} consist of from 5 to about 3500, preferably from 10 to 600, more preferably from 20 to 100, of the monomer units. It is possible to use PEG-NH _{2 of} a single chain length or PEG-NH _{2 of} different chain lengths. That is, the present invention also includes an embodiment in which a mixture of PEG-NH _{2 of} different chain length is used for the production of the sensor. In addition, this mixture may also contain one or more of the above-mentioned various TEPAs.

In this way, spacers of different lengths and also reactivity can be obtained on the carrier material of a sensor material.

After binding the spacers to the support material, the reaction substance molecules are bound to the spacers.

However, it is also possible first to bind the spacers to the reaction substance molecules, and then the spacers are bonded to the carrier material. Another alternative method of preparation is the simultaneous linking of carrier material with indicator dye and reaction substance via spacers.

The amino, hydroxy, phenolic, or thiol group of the spacers can serve not only for attachment and thus immobilization of the indicator dyes, but also act as a reactive substance at the same time.

The use of spacers of various lengths has the advantage that the sensory surface can be increased. Specifically, this means that the indicator dye molecules or the reaction substance molecules can be quasi present in several layers and still readily accessible on the carrier material.

In one embodiment of the present invention, the NH ₂ carrier material termini can be acidified using azidoacetyl chloride. Through this functionalization, click chemistry can be used as a binding mechanism. Via click chemistry, the most diverse molecules can be bound to the substrate surface.

Optical property

The optical property mentioned in the present invention may be the absorption wavelength, absorption intensity, refractive index, interference, emission wavelength, emission intensity, or fluorescence decay time.

In a preferred embodiment, the optical property is a discoloration or decolorization recognizable by the human eye.

Visible color with the human eye

As used herein, the term "human-discernible stain" or "visible" or generally "stain" to the human eye means that the stain may be in a wavelength range that can be perceived by the human eye without the aid of any aids. This wavelength range is from 350 to 750 nm, in particular from 400 to 700 nm.

In one embodiment, the optical property is a color recognizable to the human eye, and / or the indicator dye is colorless without interaction with the reaction substance.

That is, the indicator dye is colorless and is colored by the interaction with the reaction substance; or the indicator dye is colored and changes color by interaction with the reaction substance; or the indicator dye is colored and is decolorized by the interaction with the reaction substance.

Preferred embodiments

An example of a sensor system of the present invention comprises a trifluoroacetylazo dye and a lipophilic amine in a polymer layer wherein the indicator dye exhibits a color change from violet to orange upon reversible chemical reaction with the lipophilic amine. The presence of the amine in the layer leads to an orange color. The reversible reaction of the indicator dye with the amine is shifted toward the starting materials as the temperature increases, which leads to a reverse color change, whereby the orange layer turns violet again with the amine. Since the chemical reaction is reversible, the color change is reversible. By varying additions of amine, the range of color change can be adjusted. By appropriate synthesis of indicator dyes, the color change can be specially selected. By adding inert dyes to form mixed colors, a color change such as e.g. from green to red when the temperature is raised. By combining several indicator dyes with different reactivities, the temperature measurement range can be extended.

The trifluoroacetylazo dye and lipophilic amine may be physically embedded in the polymer. Therefore, the indicator dye or the amine can be washed out so that the color change is not reproducible. To maintain the color change constant and reliable, both the indicator dye and the amine can be covalently, i. chemically stable to a polymeric material (e.g., paper test strips, fabric, wound dressing, packaging material).

The indicator dye may also be attached to or embedded in amine-containing polymers (e.g., amino-PVC, aminoethylcellulose, polyethyleneimine). In this case, an additional lipophilic amine is no longer necessary.

The reaction of the trifluoroacetyl dyes is also slower (e.g., with polyHEMA) with polymers bearing hydroxyl or thiol groups.

The hydrophobic components (amine, indicator dye and polymer) can be dissolved in an organic solvent and precipitated in water as nanoparticles. These nanoparticles can then be processed by means of inkjet, valve jet or aerosol jet printing.

Examples

The present invention will be further illustrated by the following example.

The indicator dye used was N, N-dioctylamino-4-trifluoroacetyl-2-nitroazobenzene (CR546). The reaction substance used was dodecylamine.

Composition 1

• 1 mg of N, N-dioctylamino-4-trifluoroacetyl-2-nitroazobenzene (CR546)
• 0 mg dodecylamine
• 40 mg polyvinyl chloride (PCV)
• 80 mg ortho-nitrophenyl octyl ether (NPOE)
• 0.6 ml of tetrahydrofuran (THF)

Composition 2

• 1 mg of N, N-dioctylamino-4-trifluoroacetyl-2-nitroazobenzene (CR546)
• 0.66 mg dodecylamine
• 40 mg polyvinyl chloride (PCV)
• 80 mg ortho-nitrophenyl octyl ether (NPOE)
• 0.6 ml of tetrahydrofuran (THF)

Composition 3

• 1 mg of CR546
• 1.64 mg of dodecylamine
• 40 mg PVC
• 80 mg NPOE
• 0.6 ml of THF

Composition 4

• 1 mg of CR546
• 3.29 mg dodecylamine
• 40 mg PVC
• 80 mg NPOE
• 0.6 ml of THF

All five components are mixed and coated on a polyethylene terephthalate (PET) film. Thereafter, it is allowed to dry for 6 hours, and a second PET layer is placed on the indicator layer and pressed. As a result, sensor layers are obtained which have a different color at different temperatures.

At low temperatures, the layers are more yellow or orange, at higher temperatures red or purple. The color changes were reversible.

The three compositions have different sensitive measuring ranges for temperature changes due to the different amount of amine.

The results are summarized in Table 1 below. Table 1 approach composition Coloring at different temperatures Amount of CR546 (mg) Amount of dodecylamine (mg) 20 ° C 40 ° C 60 ° C 80 ° C 1 1 0 raspberry raspberry raspberry raspberry 2 1 0.66 orange dark orange dark orange, light blue cast red, blue cast 3 1 1.64 orange dark orange dark orange, light blue cast dark red, blue cast 4 1 3.29 orange bright orange light orange, towards yellow light orange, towards yellow

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 06106848 A [0002]
• JP 07179040 A [0002]
• AU 2011240892 B2 [0003]

Claims (15)

A sensor material comprising a solid support material, an indicator dye and a reaction substance, wherein the indicator dye and the reaction substance are bonded to the support material and a reactive group of the reaction substance with the indicator dye can interact with temperature changing a visual property of the indicator dye. Sensor material after Claim 1 , where the interaction is reversible. Sensor material after Claim 1 or 2 , where the interaction is a covalent or non-covalent interaction. A sensor material according to any one of the preceding claims, wherein at least one member of the group consisting of the indicator dye, the reaction substance and the reactive group is bound to the support material via a spacer. A sensor material according to any one of the preceding claims, wherein at least one member of the group consisting of the indicator dye, the reaction substance and the reactive group is bonded to the support material via spacers of different lengths. Sensor material according to one of the preceding claims, wherein the indicator dye and / or the reaction substance is / are covalently bound to the carrier material. Sensor material according to one of the preceding claims, wherein the reaction group carrying a reactive group is the carrier material. Sensor material according to one of the preceding claims, wherein the carrier material is an organic polymer material, a paper material, a textile material, a wound dressing or a packaging material. A sensor material according to any one of the preceding claims, wherein the indicator dye is an azo dye, trifluoroacetylazo dye, trifluoroacetyl dye, aldehyde dye or boronic acid dye. Sensor material according to one of the preceding claims, wherein the reactive group of the reaction substance is an amine group, hydroxy group, phenol group or thiol group. A sensor material according to any one of the preceding claims, wherein the indicator dye is an azo dye and reactive group is an amine of an amine-containing polymer selected from amino-PVC, aminoethylcellulose and polyethyleneimine, or the indicator dye is a trifluoroacetyl dye and reactive group is a hydroxy group or thiol group. A sensor material according to any one of the preceding claims, wherein the indicator dye is a trifluoroacetylazo dye and the reaction substance is a lipophilic amine. Sensor material according to one of the preceding claims, wherein the optical property is a color visible to the human eye. A sensor material according to any one of the preceding claims, wherein the interaction between the indicator dye and the reaction substance is temperature dependent by changing an optical property in a range of 0 ° C to 80 ° C. A sensor material according to any one of the preceding claims, which is an indicator film.