Uses of spider silk polypeptide fibers

Abstract

To provide a use of a shrinkable silk polypeptide fiber as an effective, inexpensive and easy-to-use sensor which can be used for determining the authenticity of a product, and to provide an effective, inexpensive and non-toxic sensor which can be used for determining the presence of liquid / moisture.SOLUTION: There is provided a use of a silk polypeptide fiber for forming a fabric including or consisting of the silk polypeptide fiber, in which the silk polypeptide fiber can be used as a sensor. Preferably, the forming of the fabric includes at least one of the shrinkage, the compression and the size reduction of the fabric. In order to form the fabric, it is preferable that the silk polypeptide fiber shrinks by at least 10% of the total length by contact with a solvent.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to the use of contractile biopolymer fibers as sensors. In a first embodiment, the sensor makes it possible to determine the authenticity of a product. In a second embodiment, the sensor makes it possible to determine the presence of a solvent. Furthermore, the present invention relates to a method for determining the authenticity of a product. Furthermore, the present invention relates to a method for determining the presence of a solvent. Furthermore, the present invention relates to the use of contractile biopolymer fibers for molding an object. Furthermore, the present invention relates to a method for molding an object. Furthermore, the present invention relates to the use of contractile biopolymer fibers as suture material or wound dressing material. [Background technology]

[0002] Counterfeit consumer goods are a common problem today. Counterfeit consumer goods are products manufactured or sold under another brand name without the brand owner's permission. Counterfeit consumer goods exist in virtually every category, including food, beverages, clothing, shoes, pharmaceuticals, electronics, auto parts, toys, and currency. Counterfeit goods are widespread worldwide; in 2008, a study by the International Chamber of Commerce (ICC) estimated the global value of all counterfeit goods to be $650 billion per year. The same study predicted that by 2015, the global value of counterfeit and pirated goods could be as high as $1.77 trillion. Counterfeit designer clothing, shoes, jewelry, and handbags are produced in varying degrees of quality. While some simply aim to deceive gullible buyers who only see the label or tag and do not know the authenticity of the product, others are more serious about imitating fashion details. Most consumers understand that they do not care whether the product they purchase is counterfeit; they simply want to purchase a cheaper product. Some counterfeit products are manufactured to be difficult to distinguish from the original. This is particularly problematic for sellers of such products, who may infringe a brand owner's trademark, patent, or copyright by selling their goods as manufactured by the brand owner.

[0003] Packaging can be designed to help reduce the risk of package theft or theft and product resale. Some packages are more theft-resistant, and some have theft-indicating seals. These anti-counterfeiting technologies can all reduce counterfeit consumer goods, unauthorized sales (diverting), material substitution, and tampering. Packaging may include authentication seals or use security printing to help indicate that the package and contents (which are also susceptible to counterfeiting) are not counterfeit. Packaging may also include anti-theft devices such as dye packs, RFID tags, or electronic article surveillance tags that can be activated or detected by devices at exit points and require special tools to deactivate. Anti-counterfeiting technologies that can be used with packaging include, for example, taggant fingerprinting (uniquely coded microscopic material verified from a database), encrypted microparticles (unpredictably arranged marks (numbers, layers, and colors) invisible to the human eye), UV printing (marks visible only under UV light), or serial barcodes.

[0004] Some of the anti-counterfeiting technologies currently in use on the market have the drawback of being ineffective, expensive, or too cumbersome to be practical.

[0005] Therefore, there is a further need for an effective, inexpensive, and easy-to-use system for use in determining the authenticity of products.

[0006] Additionally, ensuring product quality is critical in many manufacturing segments. Product quality degradation can be a serious public health and safety issue. Furthermore, product quality degradation can negatively impact the functional capabilities of the product. One of the most common events that leads to product quality degradation is the ingress of liquid / moisture into the product or the product becoming wet. For example, a wetted drug no longer has the proper quality, which may cause it to lose its therapeutic efficacy. Furthermore, a wetted electronic device no longer has the proper quality, which may not function adequately or may no longer function.

[0007] Liquid / moisture sensors / indicators currently on the market use, for example, a color change to indicate the liquid / moisture stage when a certain liquid / moisture level is exceeded. The color response depends on the absorption of water. The most well-known is silica gel blended with cobalt chloride, which changes color from purple to pink. However, cobalt chloride is toxic to both users and consumers. Alternative non-toxic systems are often expensive.

[0008] Therefore, there is a further need for an effective, inexpensive, non-toxic system that can be used to determine the presence of liquid / moisture.

[0009] The inventors of the present patent application have surprisingly found that the ability of biopolymer fibers to contract allows them to be used as sensors: the inventors realized that said contractile biopolymer fibers make it possible to determine, on the one hand, the authenticity of a product and, on the other hand, the presence of solvents, in an effective, cheap and easy-to-use manner. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] International Publication No. 2006 / 008163 Pamphlet [Patent Document 2] International Publication No. 2014 / 037453 Brochure [Non-patent literature]

[0011] [Non-Patent Document 1] “A multilingual glossary of biotechnological terms: (IUPAC Recommendations)”, Leuenberger, HGW, Nagel, B. and Kolbl, H. eds. (1995), Helvetica Chimica Acta, CH-4010 Basel, Switzerland Summary of the Invention

[0012] In a first aspect, the present invention relates to the use of contractile biopolymer fibers as sensors. In a first embodiment, the sensor makes it possible to determine the authenticity of a product. In a second embodiment, the sensor makes it possible to determine the presence of a solvent.

[0013] In a second aspect, the present invention provides a method for determining the authenticity of a product, comprising: (i) providing a contractile biopolymer fiber as a sensor; (ii) contacting the fibers with a solvent; (iii) observing whether shrinkage of the fiber occurs after contact with the solvent; wherein a shrinkage of at least 10% relative to the total length of the fiber indicates the authenticity of the product.

[0014] In a third aspect, the present invention provides a method for determining the presence of a solvent, comprising: (i) providing a contractile biopolymer fiber as a sensor; (ii) observing whether shrinkage of the fiber occurs; wherein a shrinkage of at least 10% relative to the overall length of the fiber indicates the presence of a solvent in contact with the fiber.

[0015] This summary does not necessarily describe all features of the invention, and other embodiments will become apparent from consideration of the detailed description that follows.

[0016] In a fourth aspect, the present invention relates to the use of shrinkable biopolymer fibers to form an object.

[0017] In a fifth aspect, the present invention provides a method of forming an object, comprising the steps of: (i) providing an object comprising or consisting of contractile biopolymer fibers; (ii) contacting the body with a solvent, thereby shaping the body.

[0018] In a sixth aspect, the present invention relates to the use of contractible biopolymer fibers as suture material.

[0019] In a seventh aspect, the present invention relates to the use of contractible biopolymer fibers as a wound dressing. [Brief explanation of the drawings]

[0020] [Figure 1]This figure shows the time to shrinkage, onset of shrinkage, duration, and completion of shrinkage of a biopolymer fiber depending on the effects of temperature and pH. Fibers were immersed in aqueous buffer solutions at three different pH values ​​(pH 2.8, 10 mM NaCl; pH 7.0, 10 mM NaCl; pH 11.6, 10 mM NaCl) and four different temperatures (8 °C, 16 °C, 24 °C, and 35 °C) while maintaining a constant salt content. The time range between 0 and the minimum value of each bar corresponds to the period between the first contact with the solvent / the first contact of the fiber with the solvent and the onset of shrinkage (time to shrinkage). The minimum value of each bar corresponds to the onset of shrinkage (onset of shrinkage), the maximum value of each bar corresponds to the end of the shrinkage process (completion of shrinkage), and the values ​​between the minimum and maximum values ​​of each bar correspond to the time range between the onset of shrinkage and the end / cessation of fiber shrinkage (duration of shrinkage). It was demonstrated that biopolymer fibers have specific shrinkage behaviors that are affected by temperature. The shrinkage (process) started after a certain period of time after the first contact with the solvent / first contact of the solvent with the fiber and was completed after a certain time range. Increasing the temperature shortened the period between the first contact of the solvent with the fiber and the start of shrinkage ("time to shrinkage"). Furthermore, it could be shown that increasing the temperature shortens the time range for shrinkage completion ("shrinkage completion"). Furthermore, it could be demonstrated that the biopolymer fiber has a specific shrinkage behavior that is influenced by pH. Increasing the pH (to a more basic pH) shortened the time range for shrinkage completion ("shrinkage completion"). [Figure 2]Figure 2 shows the time to contraction, onset of contraction, contraction duration, and contraction completion of two different biopolymer fibers with various diameters, depending on the effects of temperature and pH. The contraction behavior (onset of contraction and contraction duration) was determined between two different fibers with various diameters (a first silk biopolymer fiber with a diameter of approximately 250 μm and a second silk biopolymer fiber with a diameter of approximately 76 μm). The first and second biopolymer fibers were then contacted with an aqueous solvent. The time range between 0 and the minimum value of each bar corresponds to the period between the initial contact of the solvent with the fiber and the onset of contraction (time to contraction). The minimum value of each bar corresponds to the onset of contraction (onset of contraction), the maximum value of each bar corresponds to the end of the contraction process (completion of contraction), and the values ​​between the minimum and maximum values ​​of each bar correspond to the time range between the onset of contraction and the end / cessation of fiber shrinkage (contraction duration). Figure 2A represents the contraction behavior of the first biopolymer fiber. Figure 2B represents the contraction behavior of the second biopolymer fiber. It was demonstrated that biopolymer fibers have specific shrinkage behavior that is influenced by the fiber diameter. The shrinkage process began after a certain period of time following the first contact of the solvent with the fiber and was completed after a certain time range. The decrease in fiber diameter shortened the time to shrinkage and the shrinkage duration in deionized water and aqueous buffer solution. The shrinkage behavior of biopolymer fibers in deionized water (neutral pH) compared with the shrinkage behavior of biopolymer fibers in aqueous buffer solution (pH 12.8) indicates that increasing the pH (to a more basic pH) shortened the time to shrinkage and the shrinkage duration. Because the minimum temperature values ​​for the first and second biopolymer fibers were different (first biopolymer fiber: 7.5°C, second biopolymer fiber: 4.3°C), the results for this minimum temperature value cannot be directly compared between the first and second biopolymer fibers. It should be noted that higher temperatures result in shorter time to shrinkage and the shrinkage duration. DETAILED DESCRIPTION OF THE INVENTION

[0021] definition Before describing the present invention in detail below, it should be understood that the present invention is not limited to the specific methodology, protocols, and reagents described herein, as these may vary. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention, which is limited only by the appended claims. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.

[0022] Preferably, the terms used herein are defined as set forth in Non-Patent Document 1.

[0023] Several documents are cited throughout the text of this specification. Whether supra or infra, each document cited herein (including all patents, patent applications, scientific publications, manufacturer's specifications, instructions, GenBank accession number sequence entries, etc.) is hereby incorporated by reference in its entirety. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such disclosure by virtue of prior invention. In the event of a conflict between a definition or teaching of such incorporated reference and a definition or teaching recited herein, the text of this specification shall control.

[0024] The term "comprise" according to the present invention, or variations such as "comprises" or "comprising", means the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers. The term "consisting essentially of" according to the present invention means the inclusion of a stated integer or group of integers, but the exclusion of any other integer or group of integers. The term "consisting of" according to the present invention, or variations such as "consists of", means the inclusion of a stated integer or group of integers, and the exclusion of any other integer or group of integers.

[0025] As used in the context of the description of the present invention (particularly in the context of the claims), the terms "a," "an," and "the" and similar references should be construed to encompass both the singular and the plural, unless otherwise specified herein or clearly contradicted by context.

[0026] The term "sensor," as used herein, refers to an object / material that has the ability to detect an event or change in its environment and then provide a corresponding output. More specifically, the term "sensor," as used herein, refers to an object / material that reacts after contact with liquid or moisture. This reaction is optionally discernible. This is manifested as a shape change, preferably contraction.

[0027] The term "biopolymer," as used herein, refers to a large molecule or macromolecule of biological origin that is composed of many repeating subunits / repeating components. A biopolymer may be a polypeptide, such as a recombinant polypeptide. The polypeptide comprises repeating subunits / repeating components formed of amino acids. Preferably, the polypeptide is a silk polypeptide, more preferably a spider silk polypeptide. An exemplary method for producing a biopolymer that can be used in the present invention is described in U.S. Patent No. 5,999,299.

[0028] The terms "polypeptide" and "protein" are used interchangeably in the context of this invention and refer to long peptide chains of amino acids, e.g., at least 40 amino acids in length.

[0029] The term "silk polypeptide" as used herein refers to a polypeptide that exhibits a highly unusual amino acid composition compared with other polypeptides.In particular, silk polypeptide has a large amount of hydrophobic amino acids, such as glycine or alanine, but does not have (or has only a small amount of) tryptophan, for example.In addition, silk polypeptide contains highly repeated amino acid sequences or repeat units (repeated units, modules), especially in its large core domain.

[0030] Based on DNA analysis, it has been shown that all silk polypeptides are chains of repeating units, which further contain a limited set of different shorter peptide motifs. The terms "peptide motif" and "consensus sequence" can be used interchangeably herein. Generally, silk consensus sequences include GPGXX, GGX, A, B, C, D, E, F, G ... x or (GA) n These peptide motifs can be classified into four major categories: spacers and spacers. Structural roles have been assigned to these categories of peptide motifs in silk polypeptides. For example, the GPGXX motif has been suggested to be involved in a β-turn helix and provide elasticity. The GGX motif is known to be involved in a glycine-rich 31-helix. Both the GPGXX and GGX motifs are thought to be involved in the formation of an amorphous matrix connecting crystalline regions, thereby providing elasticity to the fiber. Alanine-rich motifs typically contain 6 to 9 residues and have been found to form crystalline β-sheets. Spacers typically contain charged groups and separate repeated peptide motifs into clusters. Preferably, the silk polypeptide is a spider silk polypeptide. More preferably, the silk polypeptide, e.g., the spider silk polypeptide, is a recombinant polypeptide.

[0031] The term "biopolymer fiber," as used herein, refers to a material that is significantly longer than it is wide, and that includes or consists of a biopolymer.

[0032] The term "biopolymer fiber," as used herein, further refers to a material that includes or consists of a biopolymer that is a continuous filament, staple fiber, or individual elongated pieces.

[0033] Preferably, the biopolymer fibers have a residual moisture content of 20% or less, e.g., 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. More preferably, the biopolymer fibers have a residual moisture content of 10% or less, e.g., 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. At a residual moisture content of 0%, the fibers are dry. Preferably, the moisture content of the fibers is between 2% and 10%.

[0034] It is further (alternatively or additionally) preferred that the biopolymer fibers have a linear density of 1 to 700 decitex (dtex). More preferably, the biopolymer fibers have a linear density of 10 to 300 dtex. Even more preferably, the biopolymer fibers have a linear density of 50 to 250 dtex. Most preferably, the biopolymer fibers have a linear density of 60 to 200 dtex.

[0035] It is also (alternatively or additionally) preferred that the biopolymer fibers have a thickness (diameter) between 0.5 μm and 300 μm. More preferably, the biopolymer fibers have a thickness (diameter) between 1 μm and 200 μm.

[0036] The term "biopolymer fiber" as used herein encompasses monofilament or multifilament biopolymer fibers. A monofilament biopolymer fiber is composed of a single (mono)filament. A multifilament biopolymer fiber is composed of several (mono)filaments. For example, a multifilament fiber may be composed of between 2 and 1000 (mono)filaments, for example 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, or 1000 (mono)filaments.

[0037] The term "biopolymer fiber," as used herein, further encompasses single-draw and multiply-draw (e.g., double-draw) fibers. The fibers have been drawn one or more times during their preparation process, particularly the wet-spinning process. An exemplary method for processing biopolymers into fibers that can be used in the present invention is described in U.S. Patent No. 5,629,999.

[0038] The term "biopolymer fiber" as used herein also encompasses biopolymer fibers that include or are blended with one or more additional polymers, such as additional biopolymers and / or additional plastic polymers. For example, the biopolymer fibers may include or be blended with one or more additional biopolymers selected from the group consisting of (recombinant) silk polypeptides (e.g., (recombinant) spider silk polypeptides, (recombinant) insect silk polypeptides, and / or (recombinant) Bombyx mori silk polypeptides), collagen (e.g., natural and / or recombinant collagen), keratin, and polyolefins (e.g., polylactic acid (PLA), polycaprolactone (PCL), polylactate (PLA), and / or polyhydroxybutyrate (PHB)). The additional plastic polymer may be polyacrylate. In specific examples, (i) the (recombinant) silk polypeptide fibers may comprise a (recombinant) silk polypeptide as the biopolymer and collagen as the additional biopolymer; (ii) the (recombinant) silk polypeptide fibers may comprise a (recombinant) silk polypeptide as the biopolymer and keratin as the additional biopolymer; (iii) the (recombinant) spider silk polypeptide fibers may comprise a (recombinant) spider silk polypeptide as the biopolymer and a (recombinant) insect silk polypeptide as the additional biopolymer; (iv) the (recombinant) spider silk polypeptide fibers may comprise a (recombinant) spider silk polypeptide as the biopolymer and a (recombinant) Bombyx mori silk polypeptide as the additional biopolymer; or (v) the (recombinant) spider silk polypeptide fibers may comprise a (recombinant) spider silk polypeptide as the biopolymer and another / different (recombinant) spider silk polypeptide as the additional biopolymer.

[0039] Preferably, the content of one or more additional polymers, such as biopolymers and / or plastic polymers, in the biopolymer fibers is less than 66% by weight, more preferably less than 50%, 30%, or 20% by weight, and even more preferably less than 15%, 10%, 5%, or 1% by weight. Alternatively, the content of one or more additional polymers in the biopolymer fibers is preferably at least 0.1%, at least 1%, at least 5%, at least 10%, at least 15%, at least 20%, at least 30%, or at least 50% by weight, and / or less than 66%, 50%, 30%, 20%, 10%, 5%, or 1% by weight. Thus, it is particularly preferred that the content of one or more additional polymers in the biopolymer fibers be within the range of 0.1 to 66 wt%, 1 to 66 wt%, 5 to 50 wt%, 5 to 30 wt%, 5 to 20 wt%, or 5 to 10 wt%. Such biopolymer fibers can have any desired improved properties, such as appearance, flexibility, weight, durability, water repellency, and improved manufacturing costs, which may be useful in medical, industrial, or commercial applications.

[0040] The term "contractible biopolymer fiber," as used herein, refers to a biopolymer fiber whose length is contractible / shortenable after first contact with a chemical, e.g., a solvent. In this regard, it should be noted that the entire contraction process (starting upon first contact with a chemical, e.g., a solvent, and ending upon completion of contraction) occurs entirely within the chemical, e.g., solvent. Preferably, the length of the biopolymer fiber is contractible / shortenable by at least 10%, more preferably at least 15%, even more preferably at least 25%, and most preferably at least 35% of its total length after first contact with a chemical, e.g., a solvent.

[0041] The term "contractile biopolymer fiber," as used herein, also refers to a biopolymer whose contraction (process) begins a period of time after first contact with a chemical, e.g., a solvent, and is completed after a certain time range. In this regard, it should be noted that the entire contraction process (starting a period of time after first contact with a chemical, e.g., a solvent, and ending upon completion of contraction after a certain time range) occurs entirely within the chemical, e.g., solvent. Preferably, the length of the biopolymer fiber contracts / shortens by at least 10%, more preferably at least 15%, even more preferably at least 25%, and most preferably at least 35% of its total length after first contact with a chemical, e.g., a solvent. The fiber may be a fiber produced as described in U.S. Patent No. 6,279,999.

[0042] The term "solvent" as used herein refers to an aqueous solution or a solution containing an alcohol. The aqueous solution is preferably a buffered aqueous solution, such as Tris / HCl, or water (H2O), such as industrial H2O or deionized H2O. In another preferred embodiment, the water may be tap water, rainwater, or seawater. The alcohol is preferably ethanol or isopropanol.

[0043] In this context, the term "after first contact with a chemical substance" means that the biopolymer fiber described herein is contacted with a chemical substance, e.g., a solvent, for the first time after its production / formation. The contact with the chemical substance, e.g., a solvent, preferably results in shrinkage of at least 10%, more preferably at least 15%, even more preferably at least 25%, and most preferably at least 35% of its overall length. Preferably, the shrinkage is irreversible.

[0044] The term "irreversible shrinkage," as used herein, means that the fiber does not return to its original shape without an external shock / influence, particularly without the application of a force, such as fiber extrusion, fiber stretching, or fiber drawing.

[0045] The term "product," as used herein, refers to anything that can be offered to the marketplace that can fulfill a want or need. A product may be purchased as a raw material or sold as a finished product. The product may be a pharmaceutical product (e.g., a drug), a cosmetic product, an electronic product, a mechanical product, a bag (e.g., a handbag), a shoe, or a garment. With respect to authentication, the product is preferably a fabric, e.g., a woven or knitted fabric. More preferably, the fabric, e.g., a woven or knitted fabric, is a garment.

[0046] The term "product authenticity," as used herein, refers to the determination of whether a product is original and not a copy or counterfeit.

[0047] The term "label" or "tag," as used herein, refers to a piece of polymer, e.g., fabric, that is attached to or is part of a product, or that is attached to or is part of the packaging for the product, or that contains the product. It typically contains written or printed information about the product. The biopolymer fibers described herein are preferably part of a label or tag.

[0048] The term "object," as used herein, refers to any object that can be formed from contractile biopolymer fibers. The object comprises or consists of contractile biopolymer fibers. In one embodiment, the object comprises or consists of a single contractile biopolymer fiber. In another embodiment, the object comprises or consists of two or more contractile biopolymer fibers.

[0049] Preferably, the object is a garment, an article of clothing, a medical object, an orthopedic object, a sporting item including shoes, or an outdoor item including shoes. The term "object" also encompasses shoes. Preferably, the object is a fabric, such as a woven or knitted fabric. It is particularly preferred that the fabric, such as a woven or knitted fabric, is a garment. The garment may be fashion, sport, outdoor, medical, or orthopedic garment. The garment may be a fashion article, a fashion merchandise, a shirt, a sock, a stocking, such as a compression stocking, medical stocking, or support stocking, a tight, such as a support tight, a pant, such as a sports or outdoor pant, an undergarment, such as a sports or outdoor undergarment, a glove, a hat, a storm hood, a shoe, or a bandage.

[0050] The term "object" as used herein encompasses an object comprising one or more biopolymer fibers and one or more additional polymer fibers, such as additional biopolymer fibers or additional plastic polymer fibers. For example, the object may comprise additional biopolymer fibers selected from the group consisting of (recombinant) silk polypeptide fibers (e.g., (recombinant) spider silk polypeptide fibers, (recombinant) insect silk polypeptide fibers, and / or (recombinant) silkworm (Bombyx mori) silk polypeptide fibers), collagen fibers (e.g., natural fibers and / or recombinant collagen fibers), keratin fibers, and polyolefin fibers (e.g., polylactic acid (PLA) fibers, polycaprolactone (PCL) fibers, polylactate (PLA) fibers, and / or polyhydroxybutyrate (PHB) fibers). The additional plastic polymer fibers may be polyacrylate fibers.

[0051] In specific examples, the object may comprise (i) (recombinant) silk polypeptide fibers as the biopolymer fibers and collagen fibers as the additional biopolymer fibers; (ii) (recombinant) silk polypeptide fibers as the biopolymer fibers and keratin fibers as the additional biopolymer fibers; (iii) (recombinant) spider silk polypeptide fibers as the biopolymer fibers and (recombinant) insect silk polypeptide fibers as the additional biopolymer fibers; or (iv) (recombinant) spider silk polypeptide fibers as the biopolymer fibers and (recombinant) Bombyx mori silk polypeptide fibers as the additional biopolymer fibers.

[0052] Preferably, the object is composed of at least 5%, at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 99%, or up to 100% (a) contractile biopolymer fibers, and / or the object is composed of at least 95%, at least 90%, at least 80%, at least 70%, at least 60%, at least 50%, at least 40%, at least 30%, at least 20%, at least 10%, at least 5%, or at least 1% of one or more additional polymer fibers, such as additional biopolymer fibers or additional plastic polymer fibers.

[0053] More preferably, the object is composed of at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 99%, or up to 100% (a) contractile biopolymer fibers, and / or the object is composed of at least 50%, at least 40%, at least 30%, at least 20%, at least 10%, at least 5%, or at least 1% of one or more additional polymer fibers, such as additional biopolymer fibers or additional plastic polymer fibers.

[0054] The term "shaping an object," as used herein, includes, for example, shrinking an object, compressing an object, and / or reducing the size of an object.

[0055] The term "suture material," as used herein, refers to a material used to hold body tissues or vessels together after injury or surgery. In a preferred embodiment, the suture material is a suture, e.g., a surgical suture. The application of suture material generally involves the use of a needle to which a length of thread or fiber is attached. Several different shapes, sizes, and thread materials have been developed. Typically, surgeons, physicians, dentists, podiatrists, ophthalmologists, registered nurses and other trained nursing personnel, physicians, and clinical pharmacists perform sutures. A surgical knot is used to secure the suture.

[0056] The term "wound dressing" as used herein refers to a pad or compress, especially in sterile form, for promoting wound healing and protecting the wound from further damage. Wound dressings are designed for direct contact with the wound. In a preferred embodiment, the wound dressing is adhesive.

[0057] Embodiments of the invention The inventors of the present patent application have surprisingly found that the ability of biopolymer fibers to contract allows them to be used as sensors: the inventors realized that said contractile biopolymer fibers make it possible to determine, on the one hand, the authenticity of a product and, on the other hand, the presence of solvents, in an effective, cheap and easy-to-use manner.

[0058] Thus, in a first aspect, the present invention relates to the use of a contractile biopolymer fiber as a sensor, said sensor may be a true / false sensor or a liquid / moisture sensor.

[0059] Preferably, the biopolymer fibers have a residual moisture content of 20% or less, e.g., 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less, or 0%. More preferably, the biopolymer fibers have a residual moisture content of 10% or less, e.g., 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less, or 0%. Preferably, the moisture content of the fibers is between 2% and 10%.

[0060] It is further (alternatively or additionally) preferred that the biopolymer fibers have a linear density of 1 to 700 decitex (dtex). More preferably, the biopolymer fibers have a linear density of 10 to 300 dtex. Even more preferably, the biopolymer fibers have a linear density of 50 to 250 dtex. Most preferably, the biopolymer fibers have a linear density of 60 to 200 dtex.

[0061] It is also (alternatively or additionally) preferred that the biopolymer fibers have a thickness (diameter) between 0.5 μm and 300 μm. More preferably, the biopolymer fibers have a thickness (diameter) between 1 μm and 200 μm.

[0062] In particular, biopolymer fibers have a specific shrinkage behavior. The specific shrinkage behavior can be / is influenced by temperature and / or pH. More specifically, the shrinkage (process) begins after the first contact with the solvent / after the first contact of the solvent with the fiber. Even more specifically, the shrinkage (process) begins a certain period of time after the first contact with the solvent / after the first contact of the solvent with the fiber and is completed after a certain time range. The inventors of the present patent application surprisingly found that increasing the temperature / temperature increase shortens the period between the first contact of the solvent / solvent with the fiber and the shrinkage / start of the shrinkage process ("time to shrinkage") and / or shortens the time range for which shrinkage is complete ("shrinkage period"). Furthermore, the inventors of the present patent application surprisingly found that increasing the pH (to a more basic pH) shortens the time range for which shrinkage (process) is complete ("shrinkage period"). In this regard, it should be noted that the entire shrinkage process (starting some time after first contact with the chemical, e.g., solvent, and ending upon completion of shrinkage after a certain time range) occurs entirely in the chemical, e.g., solvent.

[0063] In a preferred embodiment, the fibers are coated / finished. The inventors of the present patent application have surprisingly found that the coating can affect the shrinkage behavior. The coating / finish can extend the period between the first contact of the solvent / first contact of the solvent with the fiber and the start of the shrinkage / shrinkage process ("time to shrinkage") and / or the time range over which shrinkage is complete ("shrinkage period").

[0064] The shrinkage process preferably occurs at a temperature between 8° C. and 37° C., for example, between 15° C. and 25° C. In other words, the temperature at which the contractile biopolymer fiber is contacted with the solvent, or the solvent is contacted with the contractile biopolymer fiber, is preferably between 8° C. and 37° C., for example, between 8° C. and 35° C., between 15° C. and 25° C., between 16° C. and 24° C., or between 24° C. and 35° C. For example, the temperature may be 8° C., 9° C., 10° C., 11° C., 12° C., 13° C., 14° C., 15° C., 16° C., 17° C., 18° C., 19° C., 20° C., 21° C., 22° C., 23° C., 24° C., 25° C., 26° C., 27° C., 28° C., 29° C., 30° C., 31° C., 32° C., 33° C., 34° C., 35° C., 36° C., or 37° C.

[0065] Alternatively, or additionally, the shrinkage (process) preferably occurs at a pH between 2.8 and 12.2, for example between pH 6 and 8. In other words, the pH of the solvent is preferably between pH 2.8 and 12.2, for example between pH 6 and 8. For example, the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0066] In a first embodiment, the sensor makes it possible to determine the authenticity of the product.

[0067] Preferably, the fibers shrink by at least 10% along their length after first contact with the solvent. More preferably, the fibers shrink by at least 15% along their length after first contact with the solvent. Even more preferably, the fibers shrink by at least 25% along their length after first contact with the solvent. Most preferably, the fibers shrink by at least 35% along their length after first contact with the solvent. For example, the fibers shrink by at least 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% along their length after first contact with the solvent. Preferably, the fibers shrink between 10% and 50% of their total length after first contact with the solvent. More preferably, the fibers shrink between 15% and 35% of their total length after first contact with the solvent. Even more preferably, the fibers shrink between 15% and 25% of their total length after first contact with the solvent. For example, the fibers may exhibit shrinkage of between 10% and 50%, between 11% and 49%, between 12% and 48%, between 13% and 47%, between 14% and 46%, between 15% and 45%, between 16% and 44%, between 17% and 43%, between 18% and 42%, between 19% and 41%, between 20% and 40%, between 21% and 39%, between 22% and 38%, between 23% and 37%, between 24% and 36%, between 25% and 35%, between 26% and 34%, between 27% and 33%, between 28% and 32%, and between 29% and 31% of their total length after first contact with the solvent.

[0068] During contraction, the cross-sectional area of ​​the biopolymer fiber increases.

[0069] Preferably, shrinkage indicates the authenticity of the product.

[0070] Furthermore, the shrinkage process preferably begins between 3 and 200 seconds after the first contact with the solvent. More preferably, the shrinkage process begins between 4 and 120 seconds after the first contact with the solvent. Even more preferably, the shrinkage process begins between 20 and 60 seconds after the first contact with the solvent. Most preferably, the shrinkage process begins between 20 and 50 seconds after the first contact with the solvent. For example, the shrinkage process may begin between 3 and 200 seconds, between 4 and 150 seconds, between 5 and 140 seconds, between 6 and 130 seconds, between 7 and 120 seconds, between 8 and 110 seconds, between 9 and 100 seconds, between 10 and 60 seconds, between 11 and 58 seconds, between 12 and 55 seconds, between 13 and 52 seconds, between 14 and 50 seconds, between 15 and 49 seconds, between 16 and 48 seconds, or between 17 and 47 seconds after the first contact with the solvent. The temperature at the time of contacting the contractile biopolymer fiber with the solvent may be between 8 and 37°C, for example, between 8 and 35°C, between 15 and 25°C, between 16 and 24°C, or between 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, for example, between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0071] Preferably, the shrinkage process begins between 4 and 120 seconds after first contact with the solvent at a temperature between 8 and 35°C and / or a pH between 2.8 and 12.2. More preferably, the shrinkage process begins between 20 and 60 seconds after first contact with the solvent at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage process begins between 4 and 25 seconds after first contact with the solvent at a temperature between 24 and 35°C and / or a pH between 2.8 and 12.2. Most preferably, the shrinkage process begins between 25 and 45 seconds after first contact with the solvent at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0072] Preferably, the contraction is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). More preferably, the contraction is at least 90%, e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). It is even more preferred that shrinkage is completed to 100% after a time range (after the start of the shrinkage process) of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds. The temperature at which the shrinkable biopolymer fiber is contacted with the solvent may be between 8 and 37°C, e.g., between 8 and 35°C, 15 and 25°C, 16 and 24°C, or 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, e.g., between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0073] Preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 550 seconds (after initiation of shrinkage (process)) at a temperature of between 8 and 35°C and / or a pH of between 2.8 and 12.2. More preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 110 to 275 seconds (after the start of the shrinkage process) at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 150 seconds (after the start of the shrinkage process) at a temperature of 24 to 35°C and / or a pH of 2.8 to 12.2. Most preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 115 to 230 seconds (after initiation of shrinkage (process)) at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0074] Preferably, the shrinkage is irreversible. As mentioned above, irreversible means that the fiber does not return to its original shape without an external shock / influence, in particular without the application of a force, such as fiber extrusion, fiber stretching, or fiber drawing. Generally, it is possible to stretch a shrunken biopolymer fiber back to approximately its original shape by techniques known to those skilled in the art, such as fiber extrusion, fiber stretching, or fiber drawing. The fiber can then be contracted by contacting the fiber with a solvent a second time / again. However, the inventors of the present invention have noticed that the shrinkage behavior of such biopolymer fibers is different from biopolymer fibers that shrink after the first contact with a solvent.

[0075] The solvent may be an aqueous solution or a solution containing an alcohol. The aqueous solution is preferably a buffered aqueous solution such as Tris / HCl, or water (H2O), such as technical H2O or deionized H2O. The alcohol is preferably ethanol or isopropanol.

[0076] Preferably, the article is a fabric, such as a woven or knitted fabric. More preferably, the fabric, such as a woven or knitted fabric, is a garment.

[0077] Preferably, the contractile biopolymer fiber is part of a label or tag. The label or tag is a piece of fabric. It will be clear to those skilled in the art that the label or tag comprises two or more fibers. In fact, the label or tag is composed of multiple fibers. In other words, the label or tag comprises or consists of fibers. The label or tag may be a woven fabric. In this case, it will be clear to those skilled in the art that the label or tag comprises or consists of fibers woven together. It will also be understood by those skilled in the art that contraction in a single biopolymer fiber occurs in one dimension. In contrast, contraction in a woven fabric comprising or consisting of interwoven biopolymer fibers occurs in multiple dimensions.

[0078] The label or tag may further include written or printed information about the product. The label or tag may be affixed / attached to the product or is part of the product. If the label or tag is part of the product, it is, for example, supplied with the product. Alternatively, the label or tag is affixed / attached to packaging or is part of the packaging that contains the product. This means that the label or tag is not affixed / attached directly to the product itself, but is affixed / attached to the outer packaging in which the product is delivered / sold.

[0079] In a second embodiment, the sensor allows for determining the presence of a solvent / presence of a solvent at any time in the past, for example the presence of water, which may be tap water, rainwater or seawater.

[0080] Preferably, the fibers shrink by at least 10% along their length after first contact with the solvent. More preferably, the fibers shrink by at least 15% along their length after first contact with the solvent. Even more preferably, the fibers shrink by at least 25% along their length after first contact with the solvent. Most preferably, the fibers shrink by at least 35% along their length after first contact with the solvent. For example, the fibers shrink by at least 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% along their length after first contact with the solvent. Preferably, the fibers shrink between 10% and 50% of their total length after first contact with the solvent. More preferably, the fibers shrink between 15% and 35% of their total length after first contact with the solvent. Even more preferably, the fibers shrink between 15% and 25% of their total length after first contact with the solvent. For example, the fibers may exhibit shrinkage of between 10% and 50%, between 11% and 49%, between 12% and 48%, between 13% and 47%, between 14% and 46%, between 15% and 45%, between 16% and 44%, between 17% and 43%, between 18% and 42%, between 19% and 41%, between 20% and 40%, between 21% and 39%, between 22% and 38%, between 23% and 37%, between 24% and 36%, between 25% and 35%, between 26% and 34%, between 27% and 33%, between 28% and 32%, and between 29% and 31% of their total length after first contact with the solvent.

[0081] During contraction, the cross-sectional area of ​​the biopolymer fiber increases.

[0082] Preferably, shrinkage indicates the presence of a solvent, or the presence of a solvent at any time in the past, for example the presence of water. The water may be tap water, rain water, or sea water.

[0083] Furthermore, the shrinkage process preferably begins between 3 and 200 seconds after the first contact with the solvent. More preferably, the shrinkage process begins between 4 and 120 seconds after the first contact with the solvent. Even more preferably, the shrinkage process begins between 20 and 60 seconds after the first contact with the solvent. Most preferably, the shrinkage process begins between 20 and 50 seconds after the first contact with the solvent. For example, the shrinkage process may begin between 3 and 200 seconds, between 4 and 150 seconds, between 5 and 140 seconds, between 6 and 130 seconds, between 7 and 120 seconds, between 8 and 110 seconds, between 9 and 100 seconds, between 10 and 60 seconds, between 11 and 58 seconds, between 12 and 55 seconds, between 13 and 52 seconds, between 14 and 50 seconds, between 15 and 49 seconds, between 16 and 48 seconds, or between 17 and 47 seconds after the first contact with the solvent. The temperature at the time of contacting the contractile biopolymer fiber with the solvent may be between 8 and 37°C, for example, between 8 and 35°C, between 15 and 25°C, between 16 and 24°C, or between 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, for example, between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0084] Preferably, the shrinkage process begins between 4 and 120 seconds after first contact with the solvent at a temperature between 8 and 35°C and / or a pH between 2.8 and 12.2. More preferably, the shrinkage process begins between 20 and 60 seconds after first contact with the solvent at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage process begins between 4 and 25 seconds after first contact with the solvent at a temperature between 24 and 35°C and / or a pH between 2.8 and 12.2. Most preferably, the shrinkage process begins between 25 and 45 seconds after first contact with the solvent at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0085] Preferably, the contraction is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). More preferably, the contraction is at least 90%, e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). It is even more preferred that shrinkage is completed to 100% after a time range (after the start of the shrinkage process) of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds. The temperature at which the shrinkable biopolymer fiber is contacted with the solvent may be between 8 and 37°C, e.g., between 8 and 35°C, 15 and 25°C, 16 and 24°C, or 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, e.g., between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0086] Preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 550 seconds (after initiation of shrinkage (process)) at a temperature of between 8 and 35°C and / or a pH of between 2.8 and 12.2. More preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 110 to 275 seconds (after the start of the shrinkage process) at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 150 seconds (after the start of the shrinkage process) at a temperature of 24 to 35°C and / or a pH of 2.8 to 12.2. Most preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 115 to 230 seconds (after initiation of shrinkage (process)) at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0087] Preferably, the shrinkage is irreversible. As mentioned above, irreversible means that the fiber does not return to its original shape without an external shock / influence, in particular without the application of a force, such as fiber extrusion, fiber stretching, or fiber drawing. Generally, it is possible to stretch a shrunken biopolymer fiber back to approximately its original shape by techniques known to those skilled in the art, such as fiber extrusion, fiber stretching, or fiber drawing. The fiber can then be contracted by contacting the fiber with a solvent a second time / again. However, the inventors of the present invention have noticed that the shrinkage behavior of such biopolymer fibers is different from biopolymer fibers that shrink after the first contact with a solvent.

[0088] The solvent may be an aqueous solution, such as water, which may be tap water, rain water, or sea water.

[0089] With respect to the first or second embodiment, the biopolymer is preferably a silk polypeptide. More preferably, the biopolymer is a recombinant silk polypeptide. The (recombinant) silk polypeptide may be a spider silk polypeptide, for example, a major ampullate silk polypeptide, such as a dragline silk polypeptide, a minor ampullate silk polypeptide, or a flagelliform silk polypeptide of an orb-web spider (e.g., Araneidae or Araneoids), an insect silk polypeptide, a mussel byssus silk polypeptide, or a mixture thereof. The orb-web spider may be selected from the group consisting of Araneus diadematus, Nephila clavipes, and Latrodectus hesperus. The insect silk polypeptide may be from the Lepidoptera, in particular the Bombycidae, for example Bombyx mori. The silk polypeptide may also be from Hymenoptera, in particular Apoidea, such as Anthophila. Preferably, the silk polypeptide is a spider silk polypeptide, more preferably a recombinant spider silk polypeptide.

[0090] It is further (alternatively or additionally) preferred that the silk polypeptide is a polypeptide having an amino acid sequence that comprises or consists of at least 50%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% multiple copies of the repeating unit. More preferably, the silk polypeptide is a polypeptide having an amino acid sequence that comprises or consists of at least 95% multiple copies of the repeating unit. The repeating units may be identical or different. It is particularly preferred that the silk polypeptide comprises at least two identical repeating units. For example, silk polypeptides may have between 2 and 100 repeating units, e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 110, 111, 112, 113, 114, 115, 116, 117, 118, 1 It may comprise 0, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 100 repeating units.

[0091] It is also preferred (alternatively or additionally) that the silk polypeptide consists of between 40 and 3000 amino acids. It is more preferred that the silk polypeptide consists of between 40 and 1500 amino acids. It is even more preferred that the silk polypeptide consists of between 200 and 1200 amino acids. It is most preferred that the silk polypeptide consists of between 250 and 600 amino acids.

[0092] As mentioned above, it is particularly preferred that the silk polypeptide comprises at least two identical repeating units. In one embodiment, the repeating unit is module C (SEQ ID NO: 1) or a variant thereof, module C Cys (This module also includes module C C(SEQ ID NO: 2), and module C kappa (SEQ ID NO: 3). Module C Cys (SEQ ID NO: 2) is a variant of module C (SEQ ID NO: 1). In this module, the amino acid S (Ser) at position 25 is replaced by the amino acid C (Cys). Module C kappa (SEQ ID NO: 3) is also a variant of module C (SEQ ID NO: 1). In this module, the amino acid E (Glu) at position 20 is replaced by the amino acid K (Lys).

[0093] A module C variant differs from the reference module C from which it is derived by up to 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 amino acid changes in amino acid sequence (i.e., substitutions, additions, insertions, deletions, N-terminal truncations, and / or C-terminal truncations). Such module variants may alternatively or additionally be characterized by a degree of sequence identity to the reference module from which it is derived. Thus, module C variants have at least 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or even 99.9% sequence identity to the respective reference module C. Preferably, the sequence identity is over a contiguous stretch of at least 5, 10, 15, 18, 20, 24, 27, 28, 30, 34, 35 or more amino acids, preferably over the entire length of each reference module C.

[0094] The sequence identity may be at least 80% over the entire length of each reference module C, at least 85% over the entire length, at least 90% over the entire length, at least 95% over the entire length, at least 98% over the entire length, or at least 99% over the entire length. Alternatively, the sequence identity may be at least 80% over a contiguous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids of the respective reference module C, at least 85% over a contiguous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids, at least 90% over a contiguous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids, at least 95% over a contiguous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids, at least 98% over a contiguous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids, or at least 99% over a contiguous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids.

[0095] Fragment (or deletion) variants of module C preferably have a deletion of up to 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 amino acids at their N-terminus and / or C-terminus. Deletions may also be internal.

[0096] Furthermore, a module C variant or fragment is considered simply a module C variant or fragment in the context of the present invention if modifications to the amino acid sequence on which the variant or fragment is based do not adversely affect the ability of the silk polypeptide to function as a sensor. Those skilled in the art can easily assess whether a silk polypeptide comprising a module C variant or fragment can still function as a sensor, making it possible to, for example, determine the authenticity of a product or the presence of a solvent. In this regard, see the contraction example included in the experimental section of this patent application.

[0097] C Cys or C kappa Mutant forms are also encompassed by the present invention. Cys or C kappa Regarding the variants, the same explanations / definitions apply as given for the module C variants (see above).

[0098] Furthermore, it is particularly preferred that the silk polypeptide comprises at least one non-repeating (NR) unit. The non-repeating (NR) unit may be present at the N- and / or C-terminus. In one embodiment, the NR unit is selected from the group consisting of NR3 (SEQ ID NO: 4) or a variant thereof, NR4 (SEQ ID NO: 5) or a variant thereof, NR5 (SEQ ID NO: 6) or a variant thereof, and NR6 (SEQ ID NO: 7) or a variant thereof. The NR3 (SEQ ID NO: 4) unit is based on the amino acid sequence of ADF-3 from the spider Araneus diadematus, and the NR4 (SEQ ID NO: 5) unit is based on the amino acid sequence of ADF-4 from the spider Araneus diadematus (Patent Document 1). Furthermore, the NR5 (SEQ ID NO: 6) and NR6 (SEQ ID NO: 7) units are obtained from Latrodectus hesperus.

[0099] With respect to NR3, NR4, NR5, or NR6 unit variants, the same explanations / definitions apply as given for module C variants (see above).

[0100] Furthermore, NR3, NR4, NR5, or NR6 unit variants or fragments are considered simply NR3, NR4, NR5, or NR6 unit variants or fragments in the context of the present invention if modifications to the amino acid sequence on which the variant or fragment is based do not adversely affect the ability of the silk polypeptide to function as a sensor. Those skilled in the art can easily assess whether a silk polypeptide containing an NR3, NR4, NR5, or NR6 unit variant or fragment can still function as a sensor, for example, to determine the authenticity of a product or the presence of a solvent. In this regard, see the shrinkage example included in the experimental section of this patent application.

[0101] In one preferred embodiment, the silk polypeptide is (C) m , (C Cys ) m , (C kappa ) m , (C) m C Cys , C Cys (C) m , (C) m C Cys (C) m , (C) m NR z , N.R. z (C) m and N.R. z (C) m NR z wherein m is an integer from 8 to 96, i.e., 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95 or 96, z is an integer from 1 to 3, i.e., 1, 2, or 3, and NR represents a non-repeating unit.

[0102] In one more preferred embodiment, the silk polypeptide is C8, C 16 , C 32 , C 48 , C kappa 8. C kappa 16 , C kappa 32 , C kappa 48 , C8C Cys , C 16 C Cys , C 32 C Cys , C48 C Cys , C Cys C8, C Cys C 16 , C Cys C 32 , and C Cys C 48 is selected from the group consisting of:

[0103] As described above, biopolymer fibers have a specific shrinkage behavior. The shrinkage behavior can be further influenced by the thickness (diameter) of the biopolymer fiber. More specifically, the shrinkage process begins a certain period of time after the first contact with the solvent / first contact of the solvent with the fiber and is completed within a certain time range. The inventors of the present patent application surprisingly discovered that increasing the thickness (diameter) of the biopolymer fiber increases the period between the first contact with the solvent / first contact of the solvent with the fiber and the start of the shrinkage process, and / or increases the time range within which the shrinkage is completed. Preferably, the biopolymer fiber has a thickness (diameter) between 0.5 μm and 300 μm. More preferably, the biopolymer fiber has a thickness (diameter) between 1 μm and 200 μm. It is further preferred that the biopolymer fiber has a linear density of 1 to 700 dtex. More preferably, the biopolymer fibers have a linear density of 10 to 300 dtex. Even more preferably, the biopolymer fibers have a linear density of 50 to 250 dtex. Most preferably, the biopolymer fibers have a linear density of 60 to 200 dtex.

[0104] In view of the above, biopolymer fibers have a particular shrinkage behavior that can be / is influenced by the factors of temperature, pH, and / or thickness (diameter) of the biopolymer fiber. The shrinkage behavior can be / may be influenced by additional factors.

[0105] Furthermore, the inventors of the present patent application have surprisingly found that the degree of shrinkage relative to the overall length of a biopolymer fiber can be affected by the type of biopolymer fiber used as a starting material. In particular, the inventors have surprisingly found that the degree of shrinkage relative to the overall length of a biopolymer fiber can be / is affected by the degree of drawing of the biopolymer fiber used as a starting material. As described above, the biopolymer fiber may be a single-drawn or multiply-drawn (e.g., double-drawn) fiber. The fiber may be drawn one or more times during its preparation process, particularly during a wet-spinning process. Here, the inventors of the present patent application have observed that the higher the degree of drawing of the biopolymer fiber used as a starting material, the higher the degree of shrinkage relative to the overall length of the biopolymer fiber. Preferably, the degree of shrinkage can be adjusted in the range of 10% to 50% by changing the degree of drawing of the biopolymer fiber during and / or after the spinning process. More preferably, the degree of shrinkage can be adjusted between 10% and 35% by varying the degree of stretching of the biopolymer fiber during and / or after the spinning process. For example, the degree of shrinkage relative to the overall length of the biopolymer fiber is higher in multiply stretched (e.g., double stretched) biopolymer fibers (e.g., at least 20%) compared to single stretched biopolymer fibers (e.g., at least 10%).

[0106] Based on the above, biopolymer fibers have specific shrinkage behavior that can be / is influenced by factors such as temperature, pH, thickness (diameter) of the biopolymer fiber, and / or the type of biopolymer fiber used as starting material (e.g., single-stretched or multi-stretched biopolymer fiber).

[0107] The first aspect of the invention as described above can alternatively be restated as follows: In a first aspect, the invention relates to a sensing method in which a contractile biopolymer fiber is used.

[0108] In a second aspect, the present invention provides a method for determining the authenticity of a product, comprising: (i) providing a contractile biopolymer fiber as a sensor; (ii) (first) contacting the fibers with a solvent; (iii) observing whether shrinkage of the fibre occurs / occurs after contact with the solvent; wherein a shrinkage of at least 10% relative to the total length of the fiber indicates the authenticity of the product.

[0109] As mentioned above, the inventors of the present invention have surprisingly found that the ability of biopolymer fibers to contract allows them to be used as sensors. The inventors have realised that said contractile biopolymer fibers allow for the determination of the authenticity of products in an effective, inexpensive and easy to use manner.

[0110] Preferably, the product is a fabric, such as a woven or knitted fabric. More preferably, the fabric, such as a woven or knitted fabric, is a garment. The product may also be a bag (e.g., a handbag) or a shoe.

[0111] In step (i) of the method of the second aspect of the present invention, a contractile biopolymer fiber is provided as a sensor. Preferably, the biopolymer is a silk polypeptide. More preferably, the biopolymer is a recombinant silk polypeptide. The (recombinant) silk polypeptide may be a spider silk polypeptide, for example, a major ampullate silk polypeptide, such as a dragline silk polypeptide, a minor ampullate silk polypeptide, or a flagelliform silk polypeptide of an orb-web spider (e.g., Araneidae or Araneoids), an insect silk polypeptide, a mussel byssus silk polypeptide, or a mixture thereof. The orb-web spider may be selected from the group consisting of Araneus diadematus, Nephila clavipes, and Latrodectus hesperus. The insect silk polypeptide may also be from Hymenoptera, in particular Apoidea, for example Anthophila. Preferably, the silk polypeptide is a spider silk polypeptide, more preferably a recombinant spider silk polypeptide.

[0112] It is further (alternatively or additionally) preferred that the silk polypeptide is a polypeptide as already described in the first aspect.

[0113] Furthermore, it is particularly preferred that the silk polypeptide comprises at least one non-repeating (NR) unit as already described in the first aspect, which may be comprised at the N-terminus and / or C-terminus.

[0114] In one preferred embodiment, the silk polypeptide is (C) m , (C Cys ) m , (C kappa ) m , (C) m C Cys , CCys (C) m , (C) m C Cys (C) m , (C) m NR z , N.R. z (C) m and N.R. z (C) m NR z wherein m is an integer from 8 to 96, i.e., 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95 or 96, z is an integer from 1 to 3, i.e., 1, 2, or 3, and NR represents a non-repeating unit.

[0115] In one more preferred embodiment, the silk polypeptide is C8, C 16 , C 32 , C 48 , C kappa 8. C kappa 16 , C kappa 32 , C kappa 48 , C8C Cys , C 16 C Cys , C 32 C Cys , C 48 C Cys , C Cys C8, C Cys C 16 , C Cys C 32 , and C Cys C 48 is selected from the group consisting of:

[0116] Preferably, the biopolymer fibers have a residual moisture content of 20% or less, e.g., 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. More preferably, the biopolymer fibers have a residual moisture content of 10% or less, e.g., 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. At a residual moisture content of 0%, the fibers are dry. Preferably, the moisture content of the fibers is between 2% and 10%.

[0117] It is further (alternatively or additionally) preferred that the biopolymer fibers have a linear density of 1 to 700 decitex (dtex). More preferably, the biopolymer fibers have a linear density of 10 to 300 dtex. Even more preferably, the biopolymer fibers have a linear density of 50 to 250 dtex. Most preferably, the biopolymer fibers have a linear density of 60 to 200 dtex.

[0118] It is also (alternatively or additionally) preferred that the biopolymer fibers have a thickness (diameter) between 0.5 μm and 300 μm. More preferably, the biopolymer fibers have a thickness (diameter) between 1 μm and 200 μm.

[0119] Preferably, the contractile biopolymer fiber is part of a label or tag. The label or tag is a piece of fabric. It will be clear to those skilled in the art that the label or tag comprises two or more fibers. In fact, the label or tag is composed of multiple fibers. In other words, the label or tag comprises or consists of fibers. The label or tag may be a woven fabric. In this case, it will be clear to those skilled in the art that the label or tag comprises or consists of fibers woven together.

[0120] The label or tag may further include written or printed information about the product. The label or tag may be affixed / attached to the product or is part of the product. If the label or tag is part of the product, it is, for example, supplied with the product. Alternatively, the label or tag is affixed / attached to packaging or is part of the packaging that contains the product. This means that the label or tag is not affixed / attached directly to the product itself, but is affixed / attached to the outer packaging through which the product is delivered / sold.

[0121] In step (ii) of the method of the second aspect of the present invention, the contractile biopolymer fiber is / was contacted with a solvent. Contacting the contractile biopolymer fiber with the solvent can / was caused by dropping the solvent onto the contractile biopolymer fiber, by immersing the contractile biopolymer fiber in the solvent, or by spraying the solvent onto the contractile biopolymer fiber.

[0122] As described above, the contractile biopolymer fiber is preferably part of a label or tag. The label or tag comprises or consists of a fiber. In this case, a solvent is dripped onto the label or tag comprising or consisting of the fiber, immersed in the solvent, or sprayed onto the label or tag comprising or consisting of the fiber. To contact the solvent, the label or tag may be left on the product or on the packaging containing the product. Alternatively, the label or tag may be removed from the product to contact the label or tag with the solvent. Depending on the size of the label or tag, the label or tag may also be only partially removed from the product to contact the label or tag with the solvent.

[0123] The solvent may be an aqueous solution or a solution containing an alcohol. The aqueous solution is preferably a buffered aqueous solution such as Tris / HCl, or water (H2O), such as technical H2O or deionized H2O. The alcohol is preferably ethanol or isopropanol.

[0124] In step (iii) of the method of the second aspect of the invention, it is observed whether shrinkage of the fiber after contact with the solvent occurs / has occurred at any time in the past. The shrinkage occurs / starts after the (first) contact with the solvent in step (ii). The shrinkage is optionally discernible. The shrinkage may also be measured. For example, the length of the fiber may be measured before and after contact with the solvent to determine whether shrinkage occurs / occurs / starts.

[0125] In this regard, it should be noted that a shrinkage of at least 10%, preferably at least 15%, more preferably at least 25%, and even more preferably at least 35% relative to the total length of the fibers is indicative of the authenticity of the product, for example, a shrinkage of at least 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% relative to the total length of the fibers is indicative of the authenticity of the product.

[0126] Preferably, shrinkage of between 10% and 50% of the total length of the fibers indicates authenticity of the product. More preferably, shrinkage of between 15% and 35% of the total length of the fibers indicates authenticity of the product. Even more preferably, shrinkage of between 15% and 25% of the total length of the fibers indicates authenticity of the product. For example, shrinkage of between 10% and 50%, between 11% and 49%, between 12% and 48%, between 13% and 47%, between 14% and 46%, between 15% and 45%, between 16% and 44%, between 17% and 43%, between 18% and 42%, between 19% and 41%, between 20% and 40%, between 21% and 39%, between 22% and 38%, between 23% and 37%, between 24% and 36%, between 25% and 35%, between 26% and 34%, between 27% and 33%, between 28% and 32%, and between 29% and 31% of the total length of the fibers indicates the authenticity of the product.

[0127] During contraction, the cross-sectional area of ​​the biopolymer fiber increases.

[0128] Furthermore, the shrinkage process preferably begins between 3 and 200 seconds after the first contact with the solvent. More preferably, the shrinkage process begins between 4 and 120 seconds after the first contact with the solvent. Even more preferably, the shrinkage process begins between 20 and 60 seconds after the first contact with the solvent. Most preferably, the shrinkage process begins between 20 and 50 seconds after the first contact with the solvent. For example, the shrinkage (process) may begin between 3 and 200 seconds, between 4 and 150 seconds, between 5 and 140 seconds, between 6 and 130 seconds, between 7 and 120 seconds, between 8 and 110 seconds, between 9 and 100 seconds, between 10 and 60 seconds, between 11 and 58 seconds, between 12 and 55 seconds, between 13 and 52 seconds, between 14 and 50 seconds, between 15 and 49 seconds, between 16 and 48 seconds, or between 17 and 47 seconds after the (first) contact with the solvent. The temperature of the shrinkable biopolymer fiber at the time of contact with the solvent may be between 8 and 37°C, e.g., between 8 and 35°C, between 15 and 25°C, between 16 and 24°C, or between 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, e.g., between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0129] Preferably, the shrinkage process begins between 4 and 120 seconds after first contact with the solvent at a temperature between 8 and 35°C and / or a pH between 2.8 and 12.2. More preferably, the shrinkage process begins between 20 and 60 seconds after first contact with the solvent at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage process begins between 4 and 25 seconds after first contact with the solvent at a temperature between 24 and 35°C and / or a pH between 2.8 and 12.2. Most preferably, the shrinkage process begins between 25 and 45 seconds after first contact with the solvent at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0130] Preferably, the contraction is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). More preferably, the contraction is at least 90%, e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). It is even more preferred that shrinkage is completed to 100% after a time range (after the start of the shrinkage process) of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds. The temperature at which the shrinkable biopolymer fiber is contacted with the solvent may be between 8 and 37°C, e.g., between 8 and 35°C, 15 and 25°C, 16 and 24°C, or 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, e.g., between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0131] Preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 550 seconds (after initiation of shrinkage (process)) at a temperature of between 8 and 35°C and / or a pH of between 2.8 and 12.2. More preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 110 to 275 seconds (after the start of the shrinkage process) at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 150 seconds (after the start of the shrinkage process) at a temperature of 24 to 35°C and / or a pH of 2.8 to 12.2. Most preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 115 to 230 seconds (after initiation of shrinkage (process)) at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0132] Preferably, the shrinkage is irreversible. As mentioned above, irreversible means that the fiber does not return to its original shape without an external shock / influence, in particular without the application of a force, such as fiber extrusion, fiber stretching, or fiber drawing. Generally, it is possible to stretch a shrunken biopolymer fiber back to approximately its original shape by techniques known to those skilled in the art, such as fiber extrusion, fiber stretching, or fiber drawing. The fiber can then be contracted by contacting the fiber with a solvent a second time / again. However, the inventors of the present invention have noticed that the shrinkage behavior of such biopolymer fibers is different from biopolymer fibers that shrink after the first contact with a solvent.

[0133] It will also be understood by those skilled in the art that contraction in a single biopolymer fiber occurs in one dimension, whereas contraction in a woven fabric that includes or is made up of interwoven biopolymer fibers occurs in multiple dimensions.

[0134] With regard to the specific shrinkage behavior of shrinkable biopolymer fibers, which may be / is influenced by factors such as temperature, pH, thickness (diameter) of the biopolymer fiber, and / or the type of biopolymer fiber used as starting material (e.g., single-stretched or multi-stretched biopolymer fiber), please refer to the first aspect of the present invention.

[0135] In a third aspect, the present invention provides a method for determining the presence of a solvent, comprising: (i) providing a contractile biopolymer fiber as a sensor; (ii) observing whether contraction of the fibre occurs / has occurred, wherein a shrinkage of at least 10% relative to the overall length of the fiber indicates the presence of a solvent in contact with the fiber.

[0136] As mentioned above, the inventors of the present invention have surprisingly found that the ability of biopolymer fibers to contract allows them to be used as sensors. The inventors have realized that the contractile biopolymer fibers allow for an effective, inexpensive, and easy-to-use method of determining the presence of a solvent. In this case, the contractile biopolymer fibers function as liquid / moisture sensors.

[0137] The solvent may be an aqueous solution, such as water. The water may be tap water, rainwater, or seawater. The solvent may be present in an area or a location, such as the hull of a boat, a living space, an underground garage, or a basement. The solvent may infiltrate an area or a location, such as the hull of a boat, a living space, an underground garage, or a basement. The solvent may also be present, for example, in the packaging of a product. The solvent may infiltrate, for example, the packaging of the product. The solvent may degrade the quality of the product or destroy the product. The product may be, for example, a pharmaceutical product, a cosmetic product, an electronic product, or a mechanical product.

[0138] In step (i) of the method of the third aspect of the present invention, a contractile biopolymer fiber is provided as a sensor. Preferably, the biopolymer is a silk polypeptide. More preferably, the biopolymer is a recombinant silk polypeptide. The (recombinant) silk polypeptide may be a spider silk polypeptide, for example, a major ampullate silk polypeptide, such as a dragline silk polypeptide, a minor ampullate silk polypeptide, or a flagelliform silk polypeptide of an orb-web spider (e.g., Araneidae or Araneoids), an insect silk polypeptide, a mussel byssus silk polypeptide, or a mixture thereof. The orb-web spider may be selected from the group consisting of Araneus diadematus, Nephila clavipes, and Latrodectus hesperus. The insect silk polypeptide may also be from Hymenoptera, in particular Apoidea, for example Anthophila. Preferably, the silk polypeptide is a spider silk polypeptide, more preferably a recombinant spider silk polypeptide.

[0139] It is further (alternatively or additionally) preferred that the silk polypeptide is a polypeptide as already described in the first aspect.

[0140] Furthermore, it is particularly preferred that the silk polypeptide comprises at least one non-repeating (NR) unit as already described in the first aspect, which may be comprised at the N-terminus and / or C-terminus.

[0141] In one preferred embodiment, the silk polypeptide is (C) m , (C Cys ) m , (C kappa ) m , (C) m C Cys , CCys (C) m , (C) m C Cys (C) m , (C) m NR z , N.R. z (C) m and N.R. z (C) m NR z wherein m is an integer from 8 to 96, i.e., 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95 or 96, z is an integer from 1 to 3, i.e., 1, 2, or 3, and NR represents a non-repeating unit.

[0142] In one more preferred embodiment, the silk polypeptide is C8, C 16 , C 32 , C 48 , C kappa 8. C kappa 16 , C kappa 32 , C kappa 48 , C8C Cys , C 16 C Cys , C 32 C Cys , C 48 C Cys , C Cys C8, C Cys C 16 , C Cys C 32 , and C Cys C 48 is selected from the group consisting of:

[0143] Preferably, the biopolymer fibers have a residual moisture content of 20% or less, e.g., 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. More preferably, the biopolymer fibers have a residual moisture content of 10% or less, e.g., 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. At a residual moisture content of 0%, the fibers are dry. Preferably, the moisture content of the fibers is between 2% and 10%.

[0144] It is further (alternatively or additionally) preferred that the biopolymer fibers have a linear density of 1 to 700 decitex (dtex). More preferably, the biopolymer fibers have a linear density of 10 to 300 dtex. Even more preferably, the biopolymer fibers have a linear density of 50 to 250 dtex. Most preferably, the biopolymer fibers have a linear density of 60 to 200 dtex.

[0145] It is also (alternatively or additionally) preferred that the biopolymer fibers have a thickness (diameter) between 0.5 μm and 300 μm. More preferably, the biopolymer fibers have a thickness (diameter) between 1 μm and 200 μm.

[0146] Preferably, the contractile biopolymer fibres are part of a yarn, the yarn comprising or consisting of the contractile biopolymer fibres.

[0147] In step (ii) of the method of the third aspect of the present invention, the fiber is observed to determine whether shrinkage occurs / occurs / onsets. The shrinkage occurs / occurs / onsets after (first) contact of the solvent with the fiber. The shrinkage is optionally recognizable. The shrinkage may also be measured. For example, the length of the fiber may be measured before and after contact with the solvent to determine whether shrinkage occurs / occurs / onsets. The shrinkage may also be recognized by an electronic or mechanical device that provides an output (e.g., a signal or state change) notifying an individual (e.g., a user). For example, if a shrinkable biopolymer fiber is part of a shipment to Scotland, shrinkage of the fiber due to water intrusion (even a small amount) may be recognized by an electronic or mechanical device, which would immediately stop the shipment to Scotland. Alternatively, if a shrinkable biopolymer fiber is part of a shipment to Scotland, shrinkage of the fiber due to water intrusion (even a small amount) may also directly (without the intervention of an electronic or mechanical device) cause the immediate stop of the shipment to Scotland. Furthermore, for example, if the contractile biopolymer fiber is part of a drug packaging, shrinkage of the fiber due to water penetration will inform an individual (e.g., a user) that the product is likely no longer of its original quality. Furthermore, for example, if the contractile biopolymer fiber is part of the packaging of an electronic or mechanical device, shrinkage of the fiber due to water penetration will inform an individual (e.g., a user) that the product is likely defective and therefore should not be operated.

[0148] In this regard, it should be noted that a shrinkage of at least 10%, preferably at least 15%, more preferably at least 25%, and even more preferably at least 35% relative to the total length of the fiber indicates the presence of a solvent in contact with the fiber, for example, a shrinkage of at least 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% relative to the total length of the fiber indicates the presence of a solvent in contact with the fiber.

[0149] Preferably, a shrinkage of between 10% and 50% of the total length of the fiber indicates the presence of a solvent in contact with the fiber. More preferably, a shrinkage of between 15% and 35% of the total length of the fiber indicates the presence of a solvent in contact with the fiber. Even more preferably, a shrinkage of between 15% and 25% of the total length of the fiber indicates the presence of a solvent in contact with the fiber. For example, shrinkage of between 10% and 50%, between 11% and 49%, between 12% and 48%, between 13% and 47%, between 14% and 46%, between 15% and 45%, between 16% and 44%, between 17% and 43%, between 18% and 42%, between 19% and 41%, between 20% and 40%, between 21% and 39%, between 22% and 38%, between 23% and 37%, between 24% and 36%, between 25% and 35%, between 26% and 34%, between 27% and 33%, between 28% and 32%, and between 29% and 31% of the total length of the fiber indicates the presence of a solvent in contact with the fiber.

[0150] During contraction, the cross-sectional area of ​​the biopolymer fiber increases.

[0151] Furthermore, the shrinkage process preferably begins between 3 and 200 seconds after contact of the solvent with the fibers. More preferably, the shrinkage process begins between 4 and 120 seconds after contact of the solvent with the fibers. Even more preferably, the shrinkage process begins between 20 and 60 seconds after contact of the solvent with the fibers. Most preferably, the shrinkage process begins between 20 and 50 seconds after contact of the solvent with the fibers. For example, the shrinkage process may begin between 3 and 200 seconds, between 4 and 150 seconds, between 5 and 140 seconds, between 6 and 130 seconds, between 7 and 120 seconds, between 8 and 110 seconds, between 9 and 100 seconds, between 10 and 60 seconds, between 11 and 58 seconds, between 12 and 55 seconds, between 13 and 52 seconds, between 14 and 50 seconds, between 15 and 49 seconds, between 16 and 48 seconds, or between 17 and 47 seconds after contact of the solvent with the fibers. The temperature at the time of contact between the solvent and the fiber may be between 8 and 37°C, for example between 8 and 35°C, between 15 and 25°C, between 16 and 24°C, or between 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, for example between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12.1, or 12.2.

[0152] Preferably, shrinkage (processing) is initiated between 4 and 120 seconds after first contact with the solvent, at a temperature between 8 and 35°C and / or a pH between 2.8 and 12.2. More preferably, shrinkage (processing) is initiated between 20 and 60 seconds after contact of the solvent with the fibers, at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, shrinkage (processing) is initiated between 4 and 25 seconds after contact of the solvent with the fibers, at a temperature between 24 and 35°C and / or a pH between 2.8 and 12.2. Most preferably, shrinkage (processing) is initiated between 25 and 45 seconds after contact of the solvent with the fibers, at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0153] Preferably, the contraction is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). More preferably, the contraction is at least 90%, e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). It is even more preferred that shrinkage is completed to 100% after a time range (after the start of the shrinkage process) of 30 to 700 seconds, preferably 33 to 550 seconds, more preferably 110 to 250 seconds. The temperature at the time of contact between the solvent and the fiber may be between 8°C and 37°C, for example between 8 and 35°C, between 15 and 25°C, between 16 and 24°C, or between 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, for example between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0154] Preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 550 seconds (after initiation of shrinkage (process)) at a temperature of between 8 and 35°C and / or a pH of between 2.8 and 12.2. More preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 110 to 275 seconds (after the start of the shrinkage process) at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 150 seconds (after the start of the shrinkage process) at a temperature of 24 to 35°C and / or a pH of 2.8 to 12.2. Most preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 115 to 230 seconds (after initiation of shrinkage (process)) at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0155] Preferably, the shrinkage is irreversible. As mentioned above, irreversible means that the fiber does not return to its original shape without an external shock / influence, in particular without the application of a force, such as fiber extrusion, fiber stretching, or fiber drawing. Generally, it is possible to stretch a shrunken biopolymer fiber back to approximately its original shape by techniques known to those skilled in the art, such as fiber extrusion, fiber stretching, or fiber drawing. The fiber can then be contracted by contacting the fiber with a solvent a second time / again. However, the inventors of the present invention have noticed that the shrinkage behavior of such biopolymer fibers is different from biopolymer fibers that shrink after the first contact with a solvent.

[0156] With regard to the specific shrinkage behavior of shrinkable biopolymer fibers, which may be / is influenced by factors such as temperature, pH, thickness (diameter) of the biopolymer fiber, and / or the type of biopolymer fiber used as starting material (e.g., single-stretched or multi-stretched biopolymer fiber), please refer to the first aspect of the present invention.

[0157] In a fourth aspect, the present invention relates to the use of shrinkable biopolymer fibers to form an object.

[0158] Preferably, the biopolymer fibers have a residual moisture content of 20% or less, e.g., 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. More preferably, the biopolymer fibers have a residual moisture content of 10% or less, e.g., 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. At a residual moisture content of 0%, the fibers are dry. Preferably, the moisture content of the fibers is between 2% and 10%.

[0159] It is further (alternatively or additionally) preferred that the biopolymer fibers have a linear density of 1 to 700 decitex (dtex). More preferably, the biopolymer fibers have a linear density of 10 to 300 dtex. Even more preferably, the biopolymer fibers have a linear density of 50 to 250 dtex. Most preferably, the biopolymer fibers have a linear density of 60 to 200 dtex.

[0160] It is also (alternatively or additionally) preferred that the biopolymer fibers have a thickness (diameter) between 0.5 μm and 300 μm. More preferably, the biopolymer fibers have a thickness (diameter) between 1 μm and 200 μm.

[0161] Preferably, the object comprises or consists of contractile biopolymer fibers. In one embodiment, the object comprises / consists of a single contractile biopolymer fiber. In another embodiment, the object comprises / consists of more than one contractile biopolymer fiber, e.g., several biopolymer fibers, or simply biopolymer fibers.

[0162] The object is preferably a garment, an article of clothing, a medical object, an orthopedic object, a sports article including shoes, or an outdoor article including shoes. The object is also preferably a fabric, such as a woven or knitted fabric. The fabric, such as a woven or knitted fabric, is particularly preferably a garment. The garment may be fashion, sports, outdoor, medical, or orthopedic garment. The garment may be a fashion article, a fashion product, a shirt, a sock, a stocking, such as a compression stocking, medical stocking, or support stocking, a tight, such as a support tight, a pant, such as a sports or outdoor pant, an undergarment, such as a sports or outdoor undergarment, a glove, a hat, a storm hood, a shoe, or a bandage.

[0163] In particular, the biopolymer fibers have a specific shrinkage behavior. The specific shrinkage behavior can be / is influenced by temperature and / or pH. More specifically, the shrinkage (process) begins after a certain period of time after the first contact of the object with the solvent / after the first contact of the solvent with the object, and is completed after a certain time range. As mentioned above, the object comprises or consists of contractile biopolymer fibers. Thus, the shrinkage of the fibers ultimately results in the shaping of the object.

[0164] The inventors of the present patent application have surprisingly found that an increase in temperature / temperature increase shortens the period between first contact of the solvent with the body and the start of the shrinkage / shrinkage process ("time to shrinkage") and / or that an increase in temperature / temperature increase shortens the time range over which shrinkage is complete ("shrinkage period"). Furthermore, the inventors of the present patent application have surprisingly found that an increase in pH (to a more basic pH) shortens the time range over which shrinkage (process) is complete.

[0165] The shrinkage (process) preferably occurs at a temperature between 8°C and 37°C, for example, between 8°C and 35°C, between 15°C and 25°C, between 16°C and 24°C, or between 24°C and 35°C. In other words, the temperature at the time of contacting the object with the solvent or the time of contacting the solvent with the object is preferably between 8°C and 37°C, for example, between 8°C and 35°C, between 15°C and 25°C, between 16°C and 24°C, or between 24°C and 35°C. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C.

[0166] Alternatively, or additionally, the shrinkage (process) preferably occurs at a pH between 2.8 and 12.2, for example between pH 6 and 8. In other words, the pH of the solvent is preferably between pH 2.8 and 12.2, for example between pH 6 and 8. For example, the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0167] Preferably, the fiber shrinks by at least 10% along its length after first contact with the solvent of the object. More preferably, the fiber shrinks by at least 15% along its length after first contact with the solvent of the object. Even more preferably, the fiber shrinks by at least 25% along its length after first contact with the solvent of the object. Most preferably, the fiber shrinks by at least 35% along its length after first contact with the solvent of the object. For example, the fiber shrinks by at least 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% along its length after first contact with the solvent of the object. Preferably, the fibers shrink between 10% and 50% of their total length after first contact with the solvent of the object. More preferably, the fibers shrink between 15% and 35% of their total length after first contact with the solvent of the object. Even more preferably, the fibers shrink between 15% and 25% of their total length after first contact with the solvent of the object. For example, the fibers may exhibit shrinkage of between 10% and 50%, between 11% and 49%, between 12% and 48%, between 13% and 47%, between 14% and 46%, between 15% and 45%, between 16% and 44%, between 17% and 43%, between 18% and 42%, between 19% and 41%, between 20% and 40%, between 21% and 39%, between 22% and 38%, between 23% and 37%, between 24% and 36%, between 25% and 35%, between 26% and 34%, between 27% and 33%, between 28% and 32%, and between 29% and 31% of their total length after first contact with the solvent of the object.

[0168] During contraction, the cross-sectional area of ​​the biopolymer fiber increases.

[0169] Furthermore, it is preferred that the shrinkage process commence between 3 and 200 seconds after the object's first contact with the solvent. It is more preferred that the shrinkage process commence between 4 and 120 seconds after the object's first contact with the solvent. It is even more preferred that the shrinkage process commence between 20 and 60 seconds after the object's first contact with the solvent. It is most preferred that the shrinkage process commence between 20 and 50 seconds after the object's first contact with the solvent. For example, shrinkage may begin between 3 and 300 seconds, between 4 and 150 seconds, between 5 and 140 seconds, between 6 and 130 seconds, between 7 and 120 seconds, between 8 and 110 seconds, between 9 and 100 seconds, between 10 and 60 seconds, between 11 and 58 seconds, between 12 and 55 seconds, between 13 and 52 seconds, between 14 and 50 seconds, between 15 and 49 seconds, between 16 and 48 seconds, or between 17 and 47 seconds after first contact of the object with the solvent. The temperature of the object at the time of contact with the solvent may be between 8 and 37°C, e.g., between 8 and 35°C, between 15 and 25°C, between 16 and 24°C, or between 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, e.g., between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0170] Preferably, the shrinkage process begins between 4 and 120 seconds after first contact with the solvent, at a temperature between 8 and 35°C, and / or a pH between 2.8 and 12.2. More preferably, the shrinkage process begins between 20 and 60 seconds after first contact of the object with the solvent, at a temperature between 16 and 24°C, and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage process begins between 4 and 25 seconds after first contact of the object with the solvent, at a temperature between 24 and 35°C, and / or a pH between 2.8 and 12.2. Most preferably, the shrinkage process begins between 25 and 45 seconds after first contact of the object with the solvent, at a temperature between 16 and 24°C, and / or a pH between 6 and 8.

[0171] The object comprises or consists of contractible biopolymer fibers, the contraction of the biopolymer fibers resulting in the shaping of the object.

[0172] It should be clear to one skilled in the art that because the object comprises or consists of contractile biopolymer fibers, contacting the object with the solvent also results in contacting the contractile biopolymer fibers with the solvent.

[0173] Preferably, the contraction is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). More preferably, the contraction is at least 90%, e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). It is even more preferred that shrinkage is completed to 100% after a time range (after the start of the shrinkage process) of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds. The temperature at which the shrinkable biopolymer fiber is contacted with the solvent may be between 8 and 37°C, e.g., between 8 and 35°C, 15 and 25°C, 16 and 24°C, or 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, e.g., between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0174] Preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 550 seconds (after initiation of shrinkage (process)) at a temperature of between 8 and 35°C and / or a pH of between 2.8 and 12.2. More preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 110 to 275 seconds (after the start of the shrinkage process) at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 150 seconds (after the start of the shrinkage process) at a temperature of 24 to 35°C and / or a pH of 2.8 to 12.2. Most preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 115 to 230 seconds (after initiation of shrinkage (process)) at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0175] Preferably, the shrinkage is irreversible. As mentioned above, irreversible means that the fiber does not return to its original shape without an external shock / influence, in particular without the application of a force, such as fiber extrusion, fiber stretching, or fiber drawing. Generally, it is possible to stretch a shrunken biopolymer fiber back to approximately its original shape by techniques known to those skilled in the art, such as fiber extrusion, fiber stretching, or fiber drawing. The fiber can then be contracted by contacting the fiber with a solvent a second time / again. However, the inventors of the present invention have noticed that the shrinkage behavior of such biopolymer fibers is different from biopolymer fibers that shrink after the first contact with a solvent.

[0176] The same applies to objects that contain or consist of fibers.

[0177] The solvent may be an aqueous solution or a solution containing an alcohol. The aqueous solution is preferably a buffered aqueous solution such as Tris / HCl, or water (H2O), such as technical H2O or deionized H2O. The alcohol is preferably ethanol or isopropanol.

[0178] Preferably, the biopolymer is a silk polypeptide, more preferably a recombinant silk polypeptide as already described in the first aspect.

[0179] Furthermore, it is particularly preferred that the silk polypeptide comprises at least one non-repeating (NR) unit as already described in the first aspect. In one preferred embodiment, the silk polypeptide comprises (C) m , (C Cys ) m , (C kappa ) m , (C) m C Cys , C Cys (C) m , (C) m C Cys (C) m , (C) m NRz , N.R. z (C) m and N.R. z (C) m NR z wherein m is an integer from 8 to 96, i.e., 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95 or 96, z is an integer from 1 to 3, i.e., 1, 2, or 3, and NR represents a non-repeating unit.

[0180] In one more preferred embodiment, the silk polypeptide is C8, C 16 , C 32 , C 48 , C kappa 8. C kappa 16 , C kappa 32 , C kappa 48 , C8C Cys , C 16 C Cys , C 32 C Cys , C 48 C Cys , C Cys C8, C Cys C 16 , C Cys C 32 , and C Cys C 48 is selected from the group consisting of:

[0181] As described above, biopolymer fibers have a specific shrinkage behavior. The specific shrinkage behavior can be further influenced by the thickness (diameter) of the biopolymer fiber. More specifically, the shrinkage (process) begins a certain period of time after the first contact of the object with the solvent / the first contact of the solvent with the object and is completed after a certain time range. As described above, the object comprises or consists of a contractile biopolymer fiber. Thus, the shrinkage of the fiber ultimately results in the formation of the object. The inventors of the present patent application surprisingly found that increasing the thickness (diameter) of the biopolymer fiber increases the period between the first contact of the object with the solvent / the first contact of the solvent with the object and the start of the shrinkage (process) and / or increases the time range in which the shrinkage is completed. Preferably, the biopolymer fiber has a thickness (diameter) between 5 μm and 200 μm. More preferably, the biopolymer fiber has a thickness (diameter) between 50 μm and 150 μm.

[0182] In view of the above, biopolymer fibers have a particular shrinkage behavior that can be / is influenced by factors such as temperature, pH, and / or diameter of the biopolymer fiber.

[0183] Furthermore, the inventors of the present patent application have surprisingly found that the degree of shrinkage relative to the overall length of a biopolymer fiber can be affected by the type of biopolymer fiber used as a starting material. In particular, the inventors have surprisingly found that the degree of shrinkage relative to the overall length of a biopolymer fiber can be / is affected by the degree of drawing of the biopolymer fiber used as a starting material. As described above, the biopolymer fiber may be a single-drawn or multiple-drawn (e.g., double-drawn) fiber. The fiber has been drawn one or more times during its preparation process, particularly the wet-spinning process. Here, the inventors of the present patent application have observed that the higher the degree of drawing of the biopolymer fiber used as a starting material, the higher the degree of shrinkage relative to the overall length of the biopolymer fiber. For example, the degree of shrinkage relative to the overall length of a biopolymer fiber is higher in multiple-drawn (e.g., double-drawn) biopolymer fibers (e.g., at least 20%) compared to single-drawn biopolymer fibers (e.g., at least 10%).

[0184] Based on the above, biopolymer fibers have specific shrinkage behavior that can be / is influenced by factors such as temperature, pH, diameter of the biopolymer fiber, and / or the type of biopolymer fiber used as starting material (e.g., single-stretched or multi-stretched biopolymer fiber).

[0185] The fourth aspect of the invention as described above can alternatively be restated as follows: In a fourth aspect, the invention relates to a method of forming an object, in which contractible biopolymer fibres are used.

[0186] In a fifth aspect, the present invention provides a method of forming an object, comprising the steps of: (i) providing an object comprising or consisting of contractile biopolymer fibers; (ii) (first) contacting the body with a solvent, thereby shaping the body.

[0187] In step (i) of the method of the fifth aspect of the present invention, an object is provided that comprises or consists of a contractile biopolymer fiber. Preferably, the biopolymer is a silk polypeptide. More preferably, the biopolymer is a recombinant silk polypeptide as described above in the first aspect.

[0188] Furthermore, it is particularly preferred that the silk polypeptide comprises at least one non-repeating (NR) unit as already described in the first aspect, which may be comprised at the N-terminus and / or C-terminus.

[0189] In one preferred embodiment, the silk polypeptide is (C) m , (C Cys ) m , (C kappa ) m , (C) m C Cys , C Cys (C) m , (C) m C Cys (C) m , (C) m NR z , N.R. z (C) m and N.R. z (C) m NR z wherein m is an integer from 8 to 96, i.e., 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95 or 96, z is an integer from 1 to 3, i.e., 1, 2, or 3, and NR represents a non-repeating unit.

[0190] In one more preferred embodiment, the silk polypeptide is C8, C 16 , C 32 , C 48 , C kappa 8. C kappa 16 , C kappa 32 , C kappa 48 , C8C Cys , C 16 C Cys , C 32 C Cys , C 48 C Cys , C Cys C8, C Cys C 16 , C Cys C 32 , and C Cys C 48 is selected from the group consisting of:

[0191] Preferably, the biopolymer fibers have a residual moisture content of 20% or less, e.g., 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. More preferably, the biopolymer fibers have a residual moisture content of 10% or less, e.g., 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. At a residual moisture content of 0%, the fibers are dry. Preferably, the moisture content of the fibers is between 2% and 10%.

[0192] It is further (alternatively or additionally) preferred that the biopolymer fibers have a linear density of 1 to 700 decitex (dtex). More preferably, the biopolymer fibers have a linear density of 10 to 300 dtex. Even more preferably, the biopolymer fibers have a linear density of 50 to 250 dtex. Most preferably, the biopolymer fibers have a linear density of 60 to 200 dtex.

[0193] It is also (alternatively or additionally) preferred that the biopolymer fibers have a thickness (diameter) between 0.5 μm and 300 μm. More preferably, the biopolymer fibers have a thickness (diameter) between 1 μm and 200 μm.

[0194] As referred to in step (i) of the method of the fifth aspect of the present invention, the object comprises or consists of contractile biopolymer fibers. In one embodiment, the object comprises / consists of a single contractile biopolymer fiber. In another embodiment, the object comprises / consists of more than one contractile biopolymer fiber, for example several biopolymer fibers.

[0195] The object is preferably a garment, an article of clothing, a medical object, an orthopedic object, a sports article including shoes, or an outdoor article including shoes. The object is also preferably a fabric, such as a woven or knitted fabric. The fabric, such as a woven or knitted fabric, is particularly preferably a garment. The garment may be fashion, sports, outdoor, medical, or orthopedic garment. The garment may be a fashion article, a fashion product, a shirt, a sock, a stocking, such as a compression stocking, medical stocking, or support stocking, a tight, such as a support tight, a pant, such as a sports or outdoor pant, an undergarment, such as a sports or outdoor undergarment, a glove, a hat, a storm hood, a shoe, or a bandage.

[0196] The object provided in step (i) of the method of the fifth aspect of the invention may be attached to a molded article, for example an artificial body part. The body part may also be that of a living human being, for example a human hand if the object to be molded is a glove, or a human leg / foot if the object to be molded is a bandage / shoe.

[0197] The method of the fifth aspect of the present invention therefore allows for the production of specially designed and / or customized objects.

[0198] In step (ii) of the method of the fifth aspect of the present invention, the object is contacted with a solvent. Contacting the object with the solvent can occur by dripping the solvent onto the object, by immersing the object in the solvent, or by spraying the solvent onto the object. It should be clear to one skilled in the art that, because the object comprises or consists of contractile biopolymer fibers, contacting the object with the solvent also results in contacting the contractile biopolymer fibers with the solvent.

[0199] The solvent may be an aqueous solution or a solution containing an alcohol. The aqueous solution is preferably a buffered aqueous solution such as Tris / HCl, or water (H2O), such as technical H2O or deionized H2O. The alcohol is preferably ethanol or isopropanol.

[0200] As described above, the object comprises or consists of contractile biopolymer fibers. After the object is (first) contacted with the solvent, the biopolymer fibers contained in the object begin to shrink. This results in the shaping of the object. Preferably, the biopolymer fibers exhibit a shrinkage of at least 10%, preferably at least 15%, more preferably at least 25%, and even more preferably at least 35% of their total length after the object is (first) contacted with the solvent. For example, the biopolymer fibers exhibit a shrinkage of at least 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% of their total length after the object is (first) contacted with the solvent. Preferably, the fibers shrink between 10% and 50% of their total length after the first contact with the solvent of the object. More preferably, the fibers shrink between 15% and 35% of their total length after the first contact with the solvent of the object. Even more preferably, the fibers shrink between 15% and 25% of their total length after the first contact with the solvent of the object. For example, the fiber may exhibit shrinkage of between 10% and 50%, between 11% and 49%, between 12% and 48%, between 13% and 47%, between 14% and 46%, between 15% and 45%, between 16% and 44%, between 17% and 43%, between 18% and 42%, between 19% and 41%, between 20% and 40%, between 21% and 39%, between 22% and 38%, between 23% and 37%, between 24% and 36%, between 25% and 35%, between 26% and 34%, between 27% and 33%, between 28% and 32%, and between 29% and 31% of its total length after first contacting the body with a solvent.

[0201] Furthermore, it is preferred that the shrinkage (process) commence between 3 and 200 seconds after the (first) contact of the object with the solvent. It is more preferred that the shrinkage (process) commence between 4 and 120 seconds after the (first) contact of the object with the solvent. It is even more preferred that the shrinkage (process) commence between 20 and 60 seconds after the (first) contact of the object with the solvent. It is most preferred that the shrinkage (process) commence between 20 and 50 seconds after the (first) contact of the object with the solvent. For example, the shrinkage (process) may begin between 3 and 200 seconds, between 4 and 150 seconds, between 5 and 140 seconds, between 6 and 130 seconds, between 7 and 120 seconds, between 8 and 110 seconds, between 9 and 100 seconds, between 10 and 60 seconds, between 11 and 58 seconds, between 12 and 55 seconds, between 13 and 52 seconds, between 14 and 50 seconds, between 15 and 49 seconds, between 16 and 48 seconds, or between 17 and 47 seconds after the (first) contact of the object with the solvent. The temperature of the object at the time of contact with the solvent may be between 8 and 37°C, e.g., between 8 and 35°C, between 15 and 25°C, between 16 and 24°C, or between 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, e.g., between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0202] Preferably, the shrinkage (process) begins between 4 and 120 seconds after first contact with the solvent, at a temperature between 8 and 35°C, and / or a pH between 2.8 and 12.2. More preferably, the shrinkage (process) begins between 20 and 60 seconds after first contact of the object with the solvent, at a temperature between 16 and 24°C, and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage (process) begins between 4 and 25 seconds after first contact of the object with the solvent, at a temperature between 24 and 35°C, and / or a pH between 2.8 and 12.2. Most preferably, the shrinkage (process) begins between 25 and 45 seconds after first contact of the object with the solvent, at a temperature between 16 and 24°C, and / or a pH between 6 and 8.

[0203] Preferably, the contraction is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). More preferably, the contraction is at least 90%, e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). It is even more preferred that shrinkage is 100% complete after a time range (after the start of the shrinkage process) of 30 to 700 seconds, preferably 33 to 550 seconds, more preferably 110 to 250 seconds. The temperature of the object when contacted with the solvent may be between 8 and 37°C, for example, between 8 and 35°C, between 15 and 25°C, between 16 and 24°C, or between 24 and 35°C, and / or the pH of the solvent may be between 2.8 and 12.2, for example, between 6 and 8. For example, the temperature may be 8°C, 9°C, 10°C, 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, or 37°C, and / or the pH may be pH 2.8, 2.9, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 12.1, or 12.2.

[0204] Preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 550 seconds (after initiation of shrinkage (process)) at a temperature of between 8 and 35°C and / or a pH of between 2.8 and 12.2. More preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 110 to 275 seconds (after the start of the shrinkage process) at a temperature between 16 and 24°C and / or a pH between 2.8 and 12.2. Even more preferably, the shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 33 to 150 seconds (after the start of the shrinkage process) at a temperature of 24 to 35°C and / or a pH of 2.8 to 12.2. Most preferably, shrinkage is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 115 to 230 seconds (after initiation of shrinkage (process)) at a temperature between 16 and 24°C and / or a pH between 6 and 8.

[0205] Preferably, the shrinkage is irreversible. As mentioned above, irreversible means that the fiber does not return to its original shape without an external shock / influence, in particular without the application of a force, such as fiber extrusion, fiber stretching, or fiber drawing. Generally, it is possible to stretch a shrunken biopolymer fiber back to approximately its original shape by techniques known to those skilled in the art, such as fiber extrusion, fiber stretching, or fiber drawing. The fiber can then be contracted by contacting the fiber with a solvent a second time / again. However, the inventors of the present invention have noticed that the shrinkage behavior of such biopolymer fibers is different from biopolymer fibers that shrink after the first contact with a solvent.

[0206] The same applies to objects that include or consist of contractile biopolymer fibers.

[0207] Those skilled in the art will understand that contraction in a single biopolymer fiber occurs in one dimension, whereas contraction in an object comprising or made of biopolymer fibers may occur in multiple dimensions, for example, contraction in a woven fabric comprising or made of interwoven biopolymer fibers occurs in multiple dimensions.

[0208] The method of the fifth aspect of the present invention further comprises a step of drying the object. Drying the object can be achieved by any process known to those skilled in the art. Drying can be carried out, for example, by drying in air, baking, using a heated chamber, a vacuum chamber, a laminar flow (e.g., of a gas such as nitrogen or carbon dioxide), radiation, or a fan (at low, room, or high temperatures).

[0209] Alternatively or additionally, the method of the fifth aspect of the present invention further comprises a step of fixing the object. If the object is attached to a molded article, the object may be removed from the article after fixing. Fixing the object has the effect of preventing the formed object from further changing its form / shape, particularly the form / shape the object formed on the molded article. The object may be fixed by chemical or physical means. To fix the object, one or more reagents selected from the group consisting of adhesives and resins, such as epoxy resins or polyester resins, may be used. Fixing the object may occur by dripping one or more fixing reagents onto the object, immersing the object in one or more fixing reagents, spraying one or more fixing reagents onto the object, painting one or more fixing reagents onto the object, or brushing one or more fixing reagents onto the object. Alternatively, the object may be fixed mechanically, for example by bundling or clamping.

[0210] As mentioned above, the object may also be attached to a living human body part, for example, a human leg / foot, if the object being molded is a bandage, stocking, or shoe. In either case, contraction of the biopolymer fiber results in compression of the living human body part, for example, the human leg. This may be desirable in sports, for example, to ensure sufficient blood flow to the heart.

[0211] In a sixth aspect, the present invention relates to the use of contractile biopolymer fibers as suture materials. The contractile biopolymer fibers can be applied to wounds as suture materials. The suture material is preferably a suture, such as a surgical suture. The contractile biopolymer fibers can be part of a thread. The thread comprises or consists of the contractile biopolymer fibers.

[0212] Preferably, the biopolymer fibers have a residual moisture content of 20% or less, e.g., 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. More preferably, the biopolymer fibers have a residual moisture content of 10% or less, e.g., 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. At a residual moisture content of 0%, the fibers are dry. Preferably, the moisture content of the fibers is between 2% and 10%.

[0213] It is further (alternatively or additionally) preferred that the biopolymer fibers have a linear density of 1 to 700 decitex (dtex). More preferably, the biopolymer fibers have a linear density of 10 to 300 dtex. Even more preferably, the biopolymer fibers have a linear density of 50 to 250 dtex. Most preferably, the biopolymer fibers have a linear density of 60 to 200 dtex.

[0214] It is also (alternatively or additionally) preferred that the biopolymer fibers have a thickness (diameter) between 0.5 μm and 300 μm. More preferably, the biopolymer fibers have a thickness (diameter) between 1 μm and 200 μm.

[0215] In particular, biopolymer fibers have a specific contraction behavior. More specifically, the contraction (process) begins after a certain period of time following the first contact of the biopolymer fiber with a liquid (as a solvent) present at the wound site, such as tissue fluid, blood, or fluid from a sore, and is completed after a certain time range. Thus, contact of a biopolymer fiber as a suture with tissue fluid, blood, or fluid from a sore at the wound site (tissue fluid, blood, and fluid from a sore are aqueous solutions containing water as a solvent) induces contraction of the biopolymer fiber, which results in tightening of the wound edges after suturing. The use of contractile biopolymer fibers as sutures preferably allows for the treatment of incisions or large wounds.

[0216] Preferably, the shrinkage (process) occurs at a temperature between 36°C and 40°C, more preferably at 37°C.

[0217] Preferably, the fibers shrink by at least 10% along their length after first contact with the liquid. More preferably, the fibers shrink by at least 15% along their length after first contact with the liquid. Even more preferably, the fibers shrink by at least 25% along their length after first contact with the liquid. Most preferably, the fibers shrink by at least 35% along their length after first contact with the liquid. For example, the fibers shrink by at least 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% along their length after first contact with the liquid. Preferably, the fibers shrink between 10% and 50% of their total length after first contact with the liquid. More preferably, the fibers shrink between 15% and 35% of their total length after first contact with the liquid. Even more preferably, the fibers shrink between 15% and 25% of their total length after first contact with the liquid. For example, the fibers may exhibit shrinkage of between 10% and 50%, between 11% and 49%, between 12% and 48%, between 13% and 47%, between 14% and 46%, between 15% and 45%, between 16% and 44%, between 17% and 43%, between 18% and 42%, between 19% and 41%, between 20% and 40%, between 21% and 39%, between 22% and 38%, between 23% and 37%, between 24% and 36%, between 25% and 35%, between 26% and 34%, between 27% and 33%, between 28% and 32%, and between 29% and 31% of their total length after first contact with a liquid.

[0218] During contraction, the cross-sectional area of ​​the biopolymer fiber increases.

[0219] Furthermore, the shrinkage process preferably begins between 3 and 200 seconds after first contact with the liquid. More preferably, the shrinkage process begins between 4 and 120 seconds after first contact with the liquid. Even more preferably, the shrinkage process begins between 20 and 60 seconds after first contact with the liquid. Most preferably, the shrinkage process begins between 20 and 50 seconds after first contact with the liquid. For example, the shrinkage process may begin between 3 and 300 seconds, between 4 and 150 seconds, between 5 and 140 seconds, between 6 and 130 seconds, between 7 and 120 seconds, between 8 and 110 seconds, between 9 and 100 seconds, between 10 and 60 seconds, between 11 and 58 seconds, between 12 and 55 seconds, between 13 and 52 seconds, between 14 and 50 seconds, between 15 and 49 seconds, between 16 and 48 seconds, or between 17 and 47 seconds after first contact with the liquid.

[0220] The fluid is preferably fluid present at the wound site, such as tissue fluid, blood or fluid from a sore.

[0221] Preferably, the contraction is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). More preferably, the contraction is at least 90%, e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). It is even more preferred that the shrinkage is completed to 100% after a time range (after the start of the shrinkage process) between 30 and 700 seconds, preferably between 33 and 550 seconds, more preferably between 110 and 250 seconds.

[0222] If the moisture content or residual moisture content at the wound site is not sufficient to shrink the biopolymer fibers, the biopolymer fibers may additionally or alternatively be wetted or humidified with another solvent, for example, water or saline, such as isotonic saline.

[0223] Preferably, the shrinkage is irreversible, which, as mentioned above, means that the fiber does not return to its original shape without an external shock / influence, in particular without the application of a force, such as fiber extrusion, fiber stretching, or fiber drawing.

[0224] Preferably the fibers are coated / finished.

[0225] Preferably, the biopolymer is a silk polypeptide, more preferably a recombinant silk polypeptide as already described in the first aspect.

[0226] Furthermore, it is particularly preferred that the silk polypeptide comprises at least one non-repeating (NR) unit as already described in the first aspect. In one preferred embodiment, the silk polypeptide comprises (C) m , (C Cys ) m , (C kappa ) m , (C) m C Cys , C Cys (C) m , (C) m C Cys (C) m , (C) m NR z , N.R. z (C) m and N.R. z (C) m NR zwherein m is an integer from 8 to 96, i.e., 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95 or 96, z is an integer from 1 to 3, i.e., 1, 2, or 3, and NR represents a non-repeating unit.

[0227] In one more preferred embodiment, the silk polypeptide is C8, C 16 , C 32 , C 48 , C kappa 8. C kappa 16 , C kappa 32 , C kappa 48 , C8C Cys , C 16 C Cys , C 32 C Cys , C 48 C Cys , C Cys C8, C Cys C 16 , C Cys C 32 , and C Cys C 48 is selected from the group consisting of:

[0228] Preferably, the biopolymer fibers have a thickness (diameter) between 5 μm and 200 μm, more preferably between 50 μm and 150 μm.

[0229] The inventors of the present patent application have surprisingly found that the degree of shrinkage relative to the overall length of a biopolymer fiber can be affected by the type of biopolymer fiber used as the starting material, for example, the degree of shrinkage relative to the overall length of a biopolymer fiber is higher in multiply oriented (e.g., double oriented) biopolymer fibers (e.g., at least 20%) compared to single oriented biopolymer fibers (e.g., at least 10%).

[0230] The sixth aspect of the present invention as described above can alternatively be rephrased as follows: In the sixth aspect, the present invention relates to a method of suturing a wound, in which a contractile biopolymer fiber is used (as a suture material). In particular, the contractile biopolymer fiber is applied to a wound as a suture material. By suturing a wound with the contractile biopolymer fiber, the fiber comes into contact with liquid at the wound site, for example, tissue fluid, blood, or liquid from a sore. Contact of the biopolymer fiber as a suture with the liquid induces contraction of the biopolymer fiber, which results in tightening of the wound edges after suturing. This preferably enables treatment of incisions or large wounds in a subject. If the water content or residual water content at the wound site is insufficient for the biopolymer fiber to contract, the biopolymer fiber may additionally or alternatively be wetted or moistened with another solvent, for example, water or saline, such as isotonic saline. The sixth aspect of the present invention as described above can alternatively be rephrased as follows: In the sixth aspect, the present invention relates to a contractile biopolymer fiber for use as a suture material.

[0231] In a seventh aspect, the present invention relates to the use of contractible biopolymer fibers as a wound dressing.

[0232] In particular, the contractile biopolymer fibers are applied to a wound as a wound dressing. The wound dressing preferably comprises or consists of the contractile biopolymer fibers. The wound dressing preferably has the form of a tissue, woven fabric, or nonwoven fabric. Also, the contractile biopolymer fibers are preferably part of the tissue, woven fabric, or nonwoven fabric. In other words, the tissue, woven fabric, or nonwoven fabric preferably comprises or consists of the contractile biopolymer fibers used as a wound dressing. Techniques for producing tissue, woven fabric, or nonwoven fabric from contractile biopolymer fibers are known to those skilled in the art. Alternatively, the contractile biopolymer is preferably part of a composite material (e.g., a patch or bandage).

[0233] Preferably, the biopolymer fibers have a residual moisture content of 20% or less, e.g., 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. More preferably, the biopolymer fibers have a residual moisture content of 10% or less, e.g., 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%. At a residual moisture content of 0%, the fibers are dry. Preferably, the moisture content of the fibers is between 2% and 10%.

[0234] It is further (alternatively or additionally) preferred that the biopolymer fibers have a linear density of 1 to 700 decitex (dtex). More preferably, the biopolymer fibers have a linear density of 10 to 300 dtex. Even more preferably, the biopolymer fibers have a linear density of 50 to 250 dtex. Most preferably, the biopolymer fibers have a linear density of 60 to 200 dtex.

[0235] It is also (alternatively or additionally) preferred that the biopolymer fibers have a thickness (diameter) between 0.5 μm and 300 μm. More preferably, the biopolymer fibers have a thickness (diameter) between 1 μm and 200 μm.

[0236] In particular, biopolymer fibers have a specific contraction behavior. More specifically, the contraction (process) begins after / after a certain period of time after the first contact of the biopolymer fibers with a liquid (solvent) present at the wound site, such as tissue fluid, blood, or fluid from a sore, and is completed after a certain time range. Thus, contact of the biopolymer fibers as a wound dressing with tissue fluid, blood, or fluid from a sore at the wound site (tissue fluid, blood, and fluid from a sore are aqueous solutions containing water as a solvent) induces contraction of the biopolymer fibers as a wound dressing or component of a composite, which results in tightening of the wound edges or compression of the wound.

[0237] Preferably, the shrinkage (process) occurs at a temperature between 36°C and 40°C, more preferably at 37°C.

[0238] Preferably, the fibers shrink by at least 10% along their length after first contact with the liquid. More preferably, the fibers shrink by at least 15% along their length after first contact with the liquid. Even more preferably, the fibers shrink by at least 25% along their length after first contact with the liquid. Most preferably, the fibers shrink by at least 35% along their length after first contact with the liquid. For example, the fibers shrink by at least 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, or 35% along their length after first contact with the liquid. Preferably, the fibers shrink between 10% and 50% of their total length after first contact with the liquid. More preferably, the fibers shrink between 15% and 35% of their total length after first contact with the liquid. Even more preferably, the fibers shrink between 15% and 25% of their total length after first contact with the liquid. For example, the fibers may exhibit shrinkage of between 10% and 50%, between 11% and 49%, between 12% and 48%, between 13% and 47%, between 14% and 46%, between 15% and 45%, between 16% and 44%, between 17% and 43%, between 18% and 42%, between 19% and 41%, between 20% and 40%, between 21% and 39%, between 22% and 38%, between 23% and 37%, between 24% and 36%, between 25% and 35%, between 26% and 34%, between 27% and 33%, between 28% and 32%, and between 29% and 31% of their total length after first contact with a liquid.

[0239] During contraction, the cross-sectional area of ​​the biopolymer fiber increases.

[0240] Furthermore, the shrinkage process preferably begins between 3 and 200 seconds after first contact with the liquid. More preferably, the shrinkage process begins between 4 and 120 seconds after first contact with the liquid. Even more preferably, the shrinkage process begins between 20 and 60 seconds after first contact with the liquid. Most preferably, the shrinkage process begins between 20 and 50 seconds after first contact with the liquid. For example, the shrinkage process may begin between 3 and 300 seconds, between 4 and 150 seconds, between 5 and 140 seconds, between 6 and 130 seconds, between 7 and 120 seconds, between 8 and 110 seconds, between 9 and 100 seconds, between 10 and 60 seconds, between 11 and 58 seconds, between 12 and 55 seconds, between 13 and 52 seconds, between 14 and 50 seconds, between 15 and 49 seconds, between 16 and 48 seconds, or between 17 and 47 seconds after first contact with the liquid.

[0241] The fluid is preferably fluid present at the wound site, such as tissue fluid, blood or fluid from a sore.

[0242] Preferably, the contraction is at least 80%, e.g., at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). More preferably, the contraction is at least 90%, e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% complete after a time range of 30 to 700 seconds, preferably 33 to 550 seconds, and more preferably 110 to 250 seconds (after the start of the contraction process). It is even more preferred that the shrinkage is completed to 100% after a time range (after the start of the shrinkage process) between 30 and 700 seconds, preferably between 33 and 550 seconds, more preferably between 110 and 250 seconds.

[0243] If the moisture content or residual moisture content at the wound site is not sufficient to shrink the biopolymer fibers, the biopolymer fibers may additionally or alternatively be wetted or humidified with another solvent, for example, water or saline, such as isotonic saline.

[0244] Preferably, the shrinkage is irreversible, which, as mentioned above, means that the fiber does not return to its original shape without an external shock / influence, in particular without the application of a force, such as fiber extrusion, fiber stretching, or fiber drawing.

[0245] Preferably, the biopolymer is a silk polypeptide, more preferably a recombinant silk polypeptide as already described in the first aspect.

[0246] Furthermore, it is particularly preferred that the silk polypeptide comprises at least one non-repeating (NR) unit as already described in the first aspect. In one preferred embodiment, the silk polypeptide comprises (C) m , (C Cys ) m , (C kappa ) m , (C) m C Cys , C Cys (C) m , (C) m C Cys (C) m , (C) m NR z , N.R. z (C) m and N.R. z (C) m NR zwherein m is an integer from 8 to 96, i.e., 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95 or 96, z is an integer from 1 to 3, i.e., 1, 2, or 3, and NR represents a non-repeating unit.

[0247] In one more preferred embodiment, the silk polypeptide is C8, C 16 , C 32 , C 48 , C kappa 8. C kappa 16 , C kappa 32 , C kappa 48 , C8C Cys , C 16 C Cys , C 32 C Cys , C 48 C Cys , C Cys C8, C Cys C 16 , C Cys C 32 , and C Cys C 48 is selected from the group consisting of:

[0248] Preferably, the biopolymer fibers have a thickness (diameter) between 5 μm and 200 μm, more preferably between 50 μm and 150 μm.

[0249] The inventors of the present patent application have surprisingly found that the degree of shrinkage relative to the overall length of a biopolymer fiber can be affected by the type of biopolymer fiber used as the starting material, for example, the degree of shrinkage relative to the overall length of a biopolymer fiber is higher in multiply oriented (e.g., double oriented) biopolymer fibers (e.g., at least 20%) compared to single oriented biopolymer fibers (e.g., at least 10%).

[0250] The seventh aspect of the present invention as described above can alternatively be restated as follows: In the seventh aspect, the present invention relates to a method of treating / covering a wound with contractile biopolymer fibers (as a wound dressing). In particular, the contractile biopolymer fibers are applied to the wound as a wound dressing. The wound dressing preferably comprises or consists of contractile biopolymer fibers. The wound dressing preferably has the form of a tissue, woven fabric or nonwoven fabric. Also, the contractile biopolymer fibers are preferably part of the tissue, woven fabric or nonwoven fabric. In other words, the tissue, woven fabric or nonwoven fabric preferably comprises or consists of the contractile biopolymer fibers used as the wound dressing. Alternatively, the contractile biopolymer is preferably part of a composite material (e.g. a patch or bandage).

[0251] By treating / covering a wound with a contractile biopolymer fiber, the fiber comes into contact with liquid at the wound site, for example, tissue fluid, blood, or liquid from a sore. Contact of the biopolymer fiber as a wound dressing with liquid induces contraction of the biopolymer fiber, which results in tightening of the wound edges or compression of the wound. If the moisture content or residual moisture content at the wound site is insufficient for the biopolymer fiber to contract, the biopolymer fiber may additionally or alternatively be wetted or moistened with another solvent, for example, water or saline, such as isotonic saline. The seventh aspect of the present invention as described above can alternatively be restated as follows: In its seventh aspect, the present invention relates to a contractile biopolymer fiber for use as a wound dressing.

[0252] It should be noted that the uses and methods described herein are preferably non-therapeutic uses and / or methods.

[0253] The present invention is summarized as follows.

[0254] 1. Use of contractile biopolymer fibers as sensors.

[0255] 2. The use of contractible biopolymer fibers according to item 1, wherein the fibers have specific contraction behavior that can be affected by temperature and / or pH.

[0256] 3. The use of a shrinkable biopolymer fiber according to item 1 or 2, wherein the fiber exhibits a shrinkage of at least 10% relative to its total length after first contact with a solvent.

[0257] 4. Use of contractile biopolymer fibers according to paragraphs 1 to 3, which allows a sensor to determine the authenticity of a product.

[0258] 5. Use of a shrinkable biopolymer fiber according to paragraphs 2 to 4, wherein the shrinkage indicates the authenticity of the product.

[0259] 6. Use of a contractible biopolymer fiber according to any one of paragraphs 1 to 5, wherein a sensor makes it possible to determine the presence of a solvent.

[0260] 7. The use of a contractible biopolymer fiber according to any one of paragraphs 2 to 6, wherein the contraction indicates the presence of a solvent.

[0261] 8. A method for determining the authenticity of a product, comprising: (i) providing a contractile biopolymer fiber as a sensor; (ii) contacting the fibers with a solvent; (iii) observing whether shrinkage of the fibre occurs / occurs after contact with the solvent; A method wherein a shrinkage of at least 10% relative to the total length of the fiber indicates the authenticity of the product.

[0262] 9. A method for determining the presence of a solvent, comprising: (i) providing a contractile biopolymer fiber as a sensor; (ii) observing whether contraction of the fibre occurs / has occurred, A method wherein a shrinkage of at least 10% relative to the overall length of the fiber indicates the presence of a solvent in contact with the fiber.

[0263] 10. Use of a contractile biopolymer fiber according to any one of paragraphs 3 to 7 or the method according to paragraph 8 or 9, wherein the contraction (process) begins between 3 and 200 seconds after the (first) contact with the solvent / after the (first) contact of the solvent with the fiber.

[0264] 11. Use or method of contractile biopolymer fibers according to paragraph 10, wherein the contraction (process) starts between 4 and 120 seconds, preferably between 20 and 60 seconds, more preferably between 20 and 50 seconds after the (first) contact with the solvent / after the (first) contact of the solvent with the fiber.

[0265] 12. Use of a contractile biopolymer fiber according to any one of paragraphs 3 to 7, 10 or 11, or the method according to any one of paragraphs 8 to 11, wherein the fiber exhibits a contraction of between 10% and 50%, preferably between 15% and 35%, more preferably between 15% and 25%.

[0266] 13. Use of a contractible biopolymer fiber according to any one of paragraphs 3 to 7 or 10 to 12, or a method according to any one of paragraphs 8 to 12, wherein the contraction is at least 80% complete after a time range (after the start of the contraction process) of between 30 and 700 seconds, preferably between 33 and 550 seconds, more preferably between 110 and 250 seconds.

[0267] 14. The use of a contractile biopolymer fiber according to any one of paragraphs 2 to 7 or 10 to 13, or the method according to any one of paragraphs 8 to 13, wherein the contraction is irreversible.

[0268] 15. The use of a contractile biopolymer fiber according to any one of paragraphs 3 to 7 or 10 to 14, or the method according to any one of paragraphs 8 to 14, wherein the solvent is an aqueous solution, preferably water, or a solution comprising an alcohol.

[0269] 16. The use of a contractile biopolymer fiber according to any one of paragraphs 1 to 7 or 10 to 15, or the method according to any one of paragraphs 8 to 15, wherein the biopolymer is a silk polypeptide.

[0270] 17. The use or method of contractile biopolymer fibers according to paragraph 16, wherein the silk polypeptide is a recombinant silk polypeptide.

[0271] 18. The use or method of contractile biopolymer fibers according to paragraph 16 or 17, wherein the silk polypeptide comprises at least two identical repeating units.

[0272] 19. Module C, the repeating unit of which has a sequence according to SEQ ID NO: 1 or a variant thereof, or module C, the repeating unit of which has a sequence according to SEQ ID NO: 2 Cys and module C having the sequence according to SEQ ID NO: 3 kappa Item 19. Use or method of the contractile biopolymer fiber according to item 18, independently selected from the group consisting of:

[0273] 20. The use or method of any one of paragraphs 16 to 19, wherein the silk polypeptide comprises at least one non-repeating (NR) unit.

[0274] 21. The use of a contractile biopolymer fiber according to any one of paragraphs 4 to 7 or 10 to 20, or the method according to any one of paragraphs 8 or 10 to 20, wherein the product is a fabric.

[0275] 22. The use or method of the contractible biopolymer fiber according to paragraph 21, wherein the product is a woven or knitted fabric.

[0276] 23. The use or method of the contractible biopolymer fiber according to item 21 or 22, wherein the fabric is a garment or a piece of clothing.

[0277] 24. The use of a contractible biopolymer fiber according to any one of paragraphs 1 to 7 or 10 to 23, or the method according to any one of paragraphs 8 or 10 to 23, wherein the fiber is part of a label or tag.

[0278] 25. The use or method of the contractible biopolymer fiber according to paragraph 24, wherein the label or tag is attached to or is part of the product, or the label or tag is attached to or is part of the packaging containing the product.

[0279] 26. Use of shrinkable biopolymer fibers to mold objects.

[0280] 27. Use of a contractible biopolymer fiber according to paragraph 26, wherein the fiber has a specific contraction behavior that can be influenced by temperature and / or pH.

[0281] 28. The use of contractile biopolymer fibers according to paragraph 26 or 27, wherein the object comprises or consists of contractile biopolymer fibers.

[0282] 29. Use of a shrinkable biopolymer fiber according to paragraphs 26 to 28, wherein the fiber exhibits a shrinkage of at least 10% relative to its total length after first contact with a solvent of the object.

[0283] 30. Use of a contractible biopolymer fiber according to paragraph 29, wherein the contraction of the fiber results in the formation of an object.

[0284] 31. A method of forming an object, comprising: (i) providing an object comprising or consisting of contractile biopolymer fibers; (ii) contacting the object with a solvent, thereby shaping the object.

[0285] 32. The method of claim 31, wherein the fiber exhibits at least 10% shrinkage relative to its overall length after first contact with the solvent of the body.

[0286] 33. Use of a contractile biopolymer fiber according to paragraph 29 or 30, or the method according to paragraph 32, wherein the contraction (process) begins between 3 and 200 seconds after the (first) contact of the object with the solvent.

[0287] 34. Use or method of contractile biopolymer fibers according to paragraph 33, wherein the contraction (process) begins between 4 and 120 seconds, preferably between 20 and 60 seconds, more preferably between 20 and 50 seconds after the (first) contact of the body with the solvent.

[0288] 35. Use of a contractile biopolymer fiber according to paragraph 29, 30, 33 or 34, or the method according to any one of paragraphs 32 to 34, wherein the fiber exhibits a contraction of between 10% and 50%, preferably between 15% and 35%, more preferably between 15% and 25%.

[0289] 36. Use of a contractible biopolymer fiber according to any one of paragraphs 29, 30, 33 to 35, or a method according to any one of paragraphs 32 to 35, wherein the contraction is at least 80% complete after a time range (after the start of the contraction process) of 30 to 700 seconds, preferably 33 to 550 seconds, more preferably 110 to 250 seconds.

[0290] 37. The use of a contractile biopolymer fiber according to any one of paragraphs 29, 30, 33 to 36, or the method according to any one of paragraphs 32 to 36, wherein the contraction is irreversible.

[0291] 38. The use of a contractible biopolymer fiber according to any one of paragraphs 29, 30 or 33 to 37, or the method according to any one of paragraphs 31 to 37, wherein the solvent is an aqueous solution, preferably water, or a solution comprising an alcohol, preferably ethanol or isopropanol.

[0292] 39. The use of a contractile biopolymer fiber according to any one of paragraphs 26 to 30 or 33 to 38, or the method according to any one of paragraphs 31 to 38, wherein the biopolymer is a silk polypeptide.

[0293] 40. The use or method of contractile biopolymer fibers according to paragraph 39, wherein the silk polypeptide is a recombinant silk polypeptide.

[0294] 41. The use or method of contractile biopolymer fibers according to paragraph 39 or 40, wherein the silk polypeptide comprises at least two identical repeating units.

[0295] 42. Module C, the repeating unit of which has a sequence according to SEQ ID NO: 1 or a variant thereof, or module C, the repeating unit of which has a sequence according to SEQ ID NO: 2 Cys and module C having the sequence according to SEQ ID NO: 3 kappa Item 42. Use or method of the contractile biopolymer fiber according to item 41, independently selected from the group consisting of:

[0296] 43. The use or method of any one of paragraphs 39 to 42, wherein the silk polypeptide comprises at least one non-repeating (NR) unit.

[0297] Various modifications and variations of this invention will be apparent to those skilled in the art without departing from the scope of the invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention that are obvious to those skilled in the relevant fields are intended to be covered by the present invention.

[0298] The following figures and examples are merely illustrative of the present invention and should not be construed in any way as limiting the scope of the invention as set forth by the appended claims. [Example]

[0299] The examples presented below are for illustrative purposes only and are not intended to limit the invention described above in any way.

[0300] Example 1: Determination of the time of onset of shrinkage of the fiber after the first contact with the solvent and the period between the start of the shrinkage process and the end of the shrinkage process definition Contact with Solvent First Contact with Solvent Time to Shrinkage: The period between first contact with solvent / first contact of solvent with the fiber and the onset of shrinkage. Onset of contraction: The time at which the fiber contracts / first contraction begins Contraction period The time span between the first contraction of a fiber (the "start of contraction") and the cessation of contraction of the fiber. Shrinkage Complete End time / stop of fiber shrinkage

[0301] To determine the start time of fiber shrinkage / first shrinkage after the first contact with the solvent ("start of shrinkage"), and the time range ("shrinkage duration") between the start of fiber shrinkage and the end time / stop of shrinkage ("end of shrinkage"), C 32 Silk biopolymer multifilaments were contacted with an aqueous solvent, and the time range between contact with the solvent and the onset of contraction, and the time range between the onset of contraction and the end of contraction ("complete contraction"), were measured.

[0302] Therefore, three C 32Silk fibers were impregnated. One end of the fiber was fixed to the top of a glass cylinder. A metal nut fixed to the other end of the fiber served as a weight to fully extend the fiber. A timer was set to zero at the time of first contact with the solvent ("solvent contact"). The time range between contact with the solvent and the first movement of contraction of the fiber ("start of contraction") represented the time range "time to contraction." The time range between the first contraction of the fiber ("start of contraction") and the cessation of contraction of the fiber represented the "contraction period."

[0303] Silk biopolymer is 100% C 32 The silk protein was composed of NR4 silk protein. The silk protein was prepared as described in U.S. Patent No. 5,629,999. The protein was then processed into fibers as described in U.S. Patent No. 5,629,999. The fiber used in the experiment was a multifilament consisting of 40 monofilaments. The fiber had an overall diameter of approximately 140 μm.

[0304] The experiments were performed three times at four different temperatures (8°C, 16°C, 24°C, and 35°C). In the first experiment, the fibers were immersed in aqueous buffer solutions with three different pH values ​​(pH 2.8, 10 mM NaCl, pH 7.0, 10 mM NaCl, and pH 11.6, 10 mM NaCl) while maintaining a constant salt content. In the second experiment, the fibers were immersed in aqueous buffer solutions with different salt contents (50 mM NaCl, pH 7.0, 100 mM NaCl, pH 7.0, and 200 mM NaCl, pH 7.0) while maintaining a constant pH.

[0305] The results are shown in Figure 1. It was possible to demonstrate that the biopolymer fibers have a specific shrinkage behavior that is influenced by temperature. The shrinkage (process) started after a certain period of time after the first contact with the solvent / first contact of the solvent with the fiber and was completed after a certain time range. An increase in temperature shortened the period between the first contact of the solvent with the fiber and the start of shrinkage ("time to shrinkage"). Furthermore, it could be shown that an increase in temperature shortens the time range for shrinkage to be completed ("shrinkage completion"). Furthermore, it was possible to demonstrate that the biopolymer fibers have a specific shrinkage behavior that is influenced by pH. An increase in pH (to a more basic pH) shortened the time range for shrinkage to be completed ("shrinkage completion").

[0306] Example 2: Effect of fiber thickness on shrinkage behavior To determine the differential contraction behavior (onset and duration of contraction) between two different fibers of varying diameters, a first silk biopolymer multifilament (with a diameter of approximately 250 μm) and a second silk biopolymer fiber (with a diameter of approximately 76 μm) were contacted with an aqueous solvent. The time range between contact with the solvent and the onset and completion of contraction was measured.

[0307] Therefore, first and second silk biopolymer fibers were impregnated into glass / measuring cylinders filled with each solvent. One end of the biopolymer fiber was fixed to the top of the glass cylinder. A metal nut fixed to the other end of the fiber served as a weight to fully extend the fiber. A timer was set to zero at the time of first contact with the solvent. The time range between contact with the solvent and the first contraction of the fiber ("onset of contraction") represents the time range referred to as "time to contraction." The time range between the first contraction of the fiber ("onset of contraction") and the cessation of contraction of the fiber represents the "contraction period."

[0308] The first and second silk biopolymer fibers are 100% C 32The biopolymer fiber was composed of NR4 silk protein. The silk protein was prepared as described in U.S. Patent No. 6,279,999. The protein was then processed into fibers as described in U.S. Patent No. 6,279,999. The first biopolymer fiber used in the experiment was a multifilament containing three multifilaments, each consisting of 40 monofilaments. The three multifilaments were twisted into a yarn containing three multifilaments, each consisting of 40 monofilaments. The resulting fiber had an overall diameter of approximately 250 μm. The second biopolymer fiber used in the experiment was a multifilament consisting of 30 monofilaments with a diameter of approximately 76 μm.

[0309] Experiments were conducted at different temperatures (first biopolymer fiber: 7.5°C, 16.9°C, 22.3°C, 24.8°C; second biopolymer fiber: 4.3°C, 15.7°C, 22.63°C, 25.0°C). In the first experiment, the first and second biopolymer fibers were immersed in deionized water. In the second experiment, the first and second biopolymer fibers were immersed in a buffered aqueous solution (pH 12.8, 100 mM NaCl).

[0310] The results are shown in Figure 2. Figure 2A shows the shrinkage behavior of the first biopolymer fiber. Figure 2B shows the shrinkage behavior of the second biopolymer fiber. It was possible to demonstrate that the biopolymer fibers have a specific shrinkage behavior that is influenced by the fiber diameter. The shrinkage process started after a certain period of time after the first contact of the solvent with the fiber and was completed after a certain time range. The decrease in fiber diameter shortened the time to shrinkage and the shrinkage duration in both experiments (deionized water and aqueous buffer solution).

[0311] The shrinkage behavior of biopolymer fibers in deionized water (neutral pH) compared to that in a buffered aqueous solution (pH 12.8) shows that increasing the pH (to a more basic pH) shortened the time to shrinkage and the duration of shrinkage. Because the minimum temperature values ​​differ between the first and second biopolymer fibers (first biopolymer fiber: 7.5 °C, second biopolymer fiber: 4.3 °C), the results for this minimum temperature value are not directly comparable. It should be noted that higher temperatures result in shorter time to shrinkage and the duration of shrinkage.

Claims

1. 1. Use of spider silk polypeptide fibers to form a fabric, comprising: the fabric comprises or consists of the spider silk polypeptide fibers, 1. Use of spider silk polypeptide fibers, wherein the fibers shrink by at least 10% relative to the total length of the fibers after contact with a solvent, and this shrinkage reduces the size of the fabric, thereby shaping the fabric.

2. Use of spider silk polypeptide fiber as described in claim 1, wherein the molded fabric is clothing or shoes.

3. 3. The use of spider silk polypeptide fibers according to claim 2, wherein the article of clothing or the shoes are specially designed and / or customized articles of clothing or shoes.

4. 4. The use of spider silk polypeptide fibers according to any one of claims 1 to 3, wherein the fabric comprising or consisting of the spider silk polypeptide fibers is contacted with the solvent by: dropping the solvent onto the fabric comprising or consisting of the spider silk polypeptide fibers; immersing the fabric comprising or consisting of the spider silk polypeptide fibers in the solvent; or spraying the solvent onto the fabric comprising or consisting of the spider silk polypeptide fibers.

5. Use of spider silk polypeptide fibers according to any one of claims 1 to 4, wherein the solvent is water.

6. 6. Use of spider silk polypeptide fibers according to any one of claims 1 to 5, wherein the fabric is a woven or knitted fabric.

7. 7. Use of spider silk polypeptide fibers according to any one of claims 1 to 6, wherein the fabric comprising the spider silk polypeptide fibers comprises one or more additional polymer fibers.

8. 8. The use of spider silk polypeptide fibers according to claim 7, wherein the one or more additional polymer fibers are biopolymer fibers or plastic polymer fibers.

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