Disinfectant formulation with prolonged and residual biocidal properties

Abstract

The present invention relates to a disinfectant formulation. The disinfectant formulation comprises a biocidal compound and a silk polypeptide and provides prolonged and residual biocidal properties.

Description

[0001] DISINFECTANT FORMULATION WITH PROLONGED AND RESIDUAL BIOCIDAL PROPERTIES

[0002] The present invention relates to a disinfectant formulation. The disinfectant formulation comprises a biocidal compound and a silk polypeptide and provides prolonged and residual biocidal properties.

[0003] BACKGROUND OF THE INVENTION

[0004] Microorganisms exist everywhere in the modem world. While some are beneficial to humans and the environment, others may have significant negative consequences for contaminated articles as well as humans or animals coming in contact with them. Especially, microorganisms are prevalent in the home care environment, hospital or healthcare environment, and food service industry.

[0005] A hospital-acquired infection (HAI, alternatively a “nosocomial infection”) is an infection whose development is favoured by a hospital or healthcare environment. Such maladies typically are fungal, viral, or bacterial infections and can afflict the victim locally or systemically. Nosocomial infections can cause severe pneumonia as well as infections of the urinary tract, bloodstream, and other parts of the body.

[0006] Nosocomial infections have severe medical implications for patients and care providers. In the United States, data suggest that approximately 1.7 million instances of hospital-associated infections occur each year, with nearly 100,000 deaths resulting therefrom. European data and surveys indicate gram-negative bacterial infections alone account for 8,000-10,000 deaths each year.

[0007] Several aggravating factors contribute to the high HAI rate. Hospitals, urgent care centers, nursing homes, and similar facilities focus their treatments on those with serious illnesses and injuries. As a result, these facilities house abnormally highly concentrated populations of patients with weakened immune systems.

[0008] The most common means of HAIs is through direct or indirect contact transmission. Direct contact transmission involves a patient contacting either a contaminated patient or worker. As care providers move through the healthcare institution, they come into contact with its many patients. These workers unwittingly act in a manner analogous to bees in a garden, “pollinating” rooms and wards as they care for residents. Indirect contact transmission occurs when the patient contacts a contaminated object or surface. The healthcare environment presents an array of articles capable of passively vectoring pathogens.

[0009] Household environments also face microorganisms. Refrigerators, bathrooms, toilets at home are usually places with high microbial populations.

[0010] The food service industry further faces outbreaks in contamination of pathogens in the workplace and spreading disease out to consumers. Even though food manufacturers adopt vigorous hygiene plans and comply with tight government hygiene regulations, major outbreaks of microbes are still reported occasionally that causes serious illness among consumers.

[0011] Biocidal compounds intended for disinfection and sanitizing are generally used in disinfectant or cleaning solutions that are employed on surfaces such as floors, benches, toys, bathtubs, etc. in order to eliminate or reduce the microorganisms on said surfaces. In the recent years, the efforts have focused on the development of chemicals, which will be quite effective against microorganisms at the use dosage or when highly diluted, will have low toxicity on humans and animals and will not harm the environment.

[0012] Different types of disinfectant compounds against various microorganisms are known to the skilled person. The chemical disinfectants used according to the state of the art for the disinfection of surfaces may contain quaternary ammonium salts. Disinfectants containing sodium hypochlorite may also be used. Another effective disinfectant known in the art is hydrogen peroxide. Hydrogen peroxide is safe, non-toxic, and is regarded environment-friendly. The hydrogen peroxide-based disinfectants may be used in hospitals, laboratories, dentist offices, food / beverage processing and preparation, stockbreeding and accommodation industry and for general sanitation.

[0013] It is observed that the criteria considered when choosing the disinfectants to be used especially in the environments such as hospitals where it is necessary to ensure highly hygienic conditions are a high level of product effectiveness despite low product toxicity and the cost of the product.

[0014] A main disadvantage associated with disinfectants is that, while they can be effective at initially killing microbes, the surface is easily and quickly re-contaminated through contact, airborne microbes, and un-killed residual microbes. While some of the disinfectants would continue to offer some control if simply left on the surface, this would result in a greasy or tacky residue that would be easily negated by casual contact with the surface. Another disadvantage associated with disinfectants described in the state of the art is their short duration of action. In addition, the treated surfaces are unpleasant to touch. Thus, there is an urgent need for disinfectants who kills microbes quickly on contact and then act as residual disinfectants, but yet do not have this undesirable sticky or tacky effect. Moreover, they should be of longer effect. Such cleaners may be useful in the home care, household, hospital care, laboratory care, medical care, or food service industry.

[0015] The present inventors generated for the first time a disinfectant formulation comprising a biocidal compound and a silk polypeptide. This formulation allows surface disinfection and has prolonged and residual biocidal properties. The disinfectant formulation comprises the biocidal compound as well as the silk polypeptide in evenly distributed form. After application of the disinfectant formulation, the silk polypeptide comprised therein forms a silk polypeptide film in which the biocidal compound is embedded or entrapped. It is, thus, shielded from its environment. As the silk polypeptide has an inherent property to film surfaces, the additional use of cross-linker or binding agents is not necessary. The silk polypeptide film remains even after drying, so that the biocidal compound persists embedded or entrapped therein. Within the silk polypeptide film, the biocidal compound retains its disinfectant property and maintains protection of the surface against microbial contamination for an extended time period after its application, preferably for at least 24 hours. Moreover, the treated surface is pleasant to touch.

[0016] SUMMARY OF THE INVENTION

[0017] In a first aspect, the present invention relates to a disinfectant formulation comprising: a biocidal compound, and a silk polypeptide.

[0018] In a second aspect, the present invention relates to a method of disinfecting a surface comprising the steps of:

[0019] (i) providing a disinfectant formulation according to the first aspect, and

[0020] (i) applying the disinfectant formulation to / onto a surface, thereby disinfecting the surface.

[0021] In a third aspect, the present invention relates to an article coated on its surface with or comprising on its surface the disinfectant formulation according to the first aspect.

[0022] In a fourth aspect, the present invention relates to the use of the disinfectant formulation according to the first aspect to disinfect a surface.

[0023] In a fifth aspect, the present invention relates to the use of the disinfectant formulation according to the first aspect as disinfectant for home care, household, hospital care, laboratory care, medical care, or food service industry.

[0024] In a sixth aspect, the present invention relates to an apparatus comprising the disinfectant formulation according to the first aspect. In a seventh aspect, the present invention relates to a kit comprising the disinfectant formulation according to the first aspect, or the apparatus according to the sixth aspect.

[0025] In an eight aspect, the present invention relates to a house hold cleaner, disinfectant, sanitizer, or wet wipe comprising the disinfectant formulation according to the first aspect.

[0026] In a ninth aspect, the present invention relates to the use of a silk polypeptide to impart a prolonged and residual biocidal property to a biocidal compound.

[0027] This summary of the invention does not necessarily describe all features of the present invention. Other embodiments will become apparent from a review of the ensuing detailed description.

[0028] DETAILED DESCRIPTION OF THE INVENTION

[0029] Definitions

[0030] Before the present invention is described in detail below, it is to be understood that this invention is not limited to the particular methodology, protocols and reagents described herein as these may vary. It is also to 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 will be limited only by the appended claims. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art.

[0031] Preferably, the terms used herein are defined as described in “A multilingual glossary of biotechnological terms: (TUPAC Recommendations)”, Leuenberger, H.G.W, Nagel, B. and Kolbl, H. eds. (1995), Helvetica Chimica Acta, CH-4010 Basel, Switzerland).

[0032] Several documents are cited throughout the text of this specification. Each of the documents cited herein (including all patents, patent applications, scientific publications, manufacturer's specifications, instructions, GenBank Accession Number sequence submissions etc.), whether supra or infra, is hereby incorporated by reference in its entirety. Nothing herein is to be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention.

[0033] In the following, the elements of the present invention will be described. These elements are listed with specific embodiments. However, it should be understood that they may be combined in any manner and in any number to create additional embodiments. The variously described examples and preferred embodiments should not be construed to limit the present invention to only the explicitly described embodiments. This description should be understood to support and encompass embodiments which combine the explicitly described embodiments with any number of the disclosed and / or preferred elements. Furthermore, any permutations and combinations of all described elements in this application should be considered disclosed by the description of the present application unless the context indicates otherwise.

[0034] The term “comprise” or variations such as “comprises” or “comprising” according to the present invention 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, while excluding modifications or other integers which would materially affect or alter the stated integer. The term “consisting of’ or variations such as “consists of’ according to the present invention means the inclusion of a stated integer or group of integers and the exclusion of any other integer or group of integers.

[0035] The terms “a” and “an” and “the” and similar reference used in the context of describing the invention (especially in the context of the claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context.

[0036] As used herein, the term “about” refers to an approximately + / — 10% variation from a given value. It is to be understood that such a variation is always included in any given value provided herein, whether or not it is specifically referred to.

[0037] The term “silk polypeptide”, as used herein, refers to a polypeptide which comprises repetitive units / repeating building blocks made of amino acids. Specifically, a silk polypeptide possesses large quantities of hydrophobic amino acids such as glycine or alanine. Especially, the highly repetitive amino acid sequences are located in the large core domain of the silk polypeptide.

[0038] All silk polypeptides used herein comprise chains of repetitive units which further comprise a limited set of distinct shorter peptide motifs. The expressions “peptide motif’ and “consensus sequence” can be used interchangeably herein. Generally, the silk consensus sequences can be grouped into four major categories: GPGXX, GGX, Axor (GA)nand spacers. These categories of peptide motifs in silk proteins have been assigned structural roles. For example, it has been suggested that the GPGXX motif is involved in a P-turn spiral, probably providing elasticity. The GGX motif is known to be responsible for a glycine-rich 3i-helix. Both GPGXX and GGX motifs are thought to be involved in the formation of an amorphous matrix that connects crystalline regions, thereby providing elasticity of the fiber. Alanine-rich motifs typically contain 6 to 9 residues and have been found to form crystalline P-sheets. The spacers typically contain charged groups and separate the iterated peptide motifs into clusters. An exemplarily process for producing the silk polypeptides used herein is described in WO 2006 / 008163 and in WO 2011 / 120690.

[0039] The terms “polypeptide” and “protein” are used interchangeably in the context of the present invention.

[0040] The silk polypeptides can perform self-assembly. The term “self-assembly”, as used herein, refers to a process in which a disordered system of pre-existing silk polypeptides forms an organized structure or pattern as a consequence of specific, local interactions (e.g. van der Waals forces, hydrophobic interactions, hydrogen bonds, and / or salt-bridges, etc.) among the silk polypeptides themselves, without external direction or triggers, although external factors might influence speed and nature of self-assembly. This particularly means that when two or more disordered and / or unfolded silk polypeptides are brought into contact, they interact with each other and consequently form a three-dimensional structure. The change from a disordered system to an organized structure or pattern during self-assembly is characterized by a transition from a fluid state to a gel-like and / or solid state and a corresponding increase in viscosity. The transition from a fluid state to a gel-like state can be monitored, for example, by optical measurement or rheology. These techniques are known to the skilled person. The transition from a fluid state to a solid state can be monitored, for example, using optical methods. The self-assembly specifically allows the silk polypeptides to film or coat surfaces. Silk polypeptides form non-covalent linkages with surfaces that they cover. No cross-linking agents or binding agents are, therefore, required.

[0041] Preferably, the silk polypeptide is a recombinant silk polypeptide. More preferably, the silk polypeptide is a spider silk polypeptide. Even more preferably, the spider silk polypeptide is a recombinant spider silk polypeptide.

[0042] The term “non-covalent linkage” means a type of linkage (interaction) that does not involve the sharing of pairs of electrons, but rather involves more dispersed variations of electromagnetic interactions, ionic (electrostatic) interactions, hydrophobic interactions, and / or van der Waals interactions.

[0043] The term “disinfectant”, as used herein, refers to a substance or a mixture of substances (including solutions) that destroy or (irreversibly) inactivate bacteria, fungi and / or viruses, but not necessarily bacterial spores, in an inanimate environment or on a surface (e.g. in or on a substrate or an article).

[0044] Disinfectants are used in private, public or industrial areas for the disinfection of air, water (e.g. swimming pools, aquariums, bathing waters), surfaces, materials, equipment and furniture. For the food and feed area, products are used for the disinfection of equipment, containers, consumption utensils, surfaces and pipework associated with the production, transport, storage or consumption of food, feed or drinks (including drinking water) for humans and animals. Common active biocidal substances in disinfectants are isopropanol, n-propanol, ethanol and quaternary (from Latin quaternarius = of four each) ammonium compounds.

[0045] The term “disinfectant formulation”, as used herein, refers to a formulation comprising a biocidal compound and a silk polypeptide. Specifically, the disinfectant formulation of the present invention is applied to surfaces for disinfection. These surfaces are preferably solid / hard and / or non-porous surfaces. After application of the disinfectant formulation, the silk polypeptide comprised therein forms a silk polypeptide film in which the biocidal compound is embedded or entrapped. It is, thus, shielded from its environment. As the silk polypeptide has an inherent property to film surfaces, the additional use of cross-linker or binding agents is not necessary. The silk polypeptide film remains even after drying, so that the biocidal compound persists embedded or entrapped therein. Within the silk polypeptide film, the biocidal compound retains its disinfectant property and maintains protection of surfaces against microbial contamination for an extended time period after its application, preferably for at least 24 hours, e.g. 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, or 72 hours.

[0046] Specifically, the disinfectant formulation of the present invention imparts a residual biocidal property for at least 24 hours, e.g. 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, or 72 hours, after deposition.

[0047] The term “Residual biocidal property”, as used herein, refers to achieving at least 99.9% microbial reduction in the Environmental Protection Agency (EPA)-approved 24 hour Residual Self Sanitizing (RSS) test methodology for dried product residues on solid / hard, non-porous surfaces (EPA#01-lA). That is, the formulations as described herein displaying residual biocidal properties are preferably able to deliver at least 99.9% microbial reduction after a 12-abrasion and 5- reinoculation 24 hour testing regime.

[0048] The disinfectant formulation of the present invention may be provided as concentrated liquid, e.g. concentrated solution, (i.e. as a “concentrate”) or as a ready-to-use (i.e. an “RTU”) liquid, e.g. solution, either of which may be applied to a surface to be treated, e.g. a solid / hard surface, using known application means. Some exemplary disinfectant formulations in liquid form, such as in solution form, may be applied to a woven or non-woven substrate to make a wipe, wherein the wipe is used to apply the disinfectant formulation to a surface to be treated with the formulation. An advantage of using a wipe is that it may be disposed of after use, such that it will not be reused to apply the formulation to more than one surface. The term “microorganism (alternatively microbe)”, as used herein, refers to any microscopic organism studied by microbiologists or found in the use environment of a treated surface or article. Such organisms include, but are not limited to, bacteria, viruses, fungi as well as other single-celled organisms such as mould, mildew, and algae.

[0049] The term “biocidal compound”, as used herein, refers to a compound having biocidal properties, specifically microbicidal properties. In other words, the biocidal compound is a chemical substance intended to destroy, kill, deter, render harmless, or exert a controlling effect on any undesirable organisms, specifically microorganism, considered harmful or not. The microorganisms are exemplified by bacteria, yeasts, and fungi. Other single-celled organisms such as mould, mildew, and algae may also be treated. Harmful microorganisms can also be designated pathogenic microorganisms herein.

[0050] The biocidal compound can present a risk for human and animal health, but also for the environment. From an etymological point of view “bios” means “the life” and “-cide” means “who kills”.

[0051] The biocidal compound described herein is part of a disinfectant formulation. When, after application of the disinfectant formulation, a silk polypeptide film is formed, the biocidal compound remains entrapped or embedded within the film. In this way, the human, the animal or the environment can be protected from the biocidal compound and its potentially health damaging properties.

[0052] Preferably, the biocidal compound is an antimicrobial chemical substance, antiviral chemical substance, antifungal chemical substance, which includes germicides, antibiotics, antibacterials, antivirals, antifungals, antiprotozoal s, and antiparasites.

[0053] The term “surface”, as used herein, refers to any surface which is prone to infestation by microorganisms. The term “surface”, as used herein, further refers to any surface on which microorganisms can occur / attach. Specifically, the surface is a surface with contact to food / associated with food preparation, a household surface, a surface in a health care environment, a surface associated with hospital environments, a surface associated in a medical laboratory, a surface in a medical treatment environment, a surface in the institutional and hospitality environment, a lavatory fixture, a lavatory appliance, a wall, and a flooring surface. The term “surface,” as used herein, also refers to any surface (whether in a homely, an industrial, or a medical setting) that provides an interphase between a liquid phase and a substrate or that provides an interphase between a gaseous phase and a substrate. The surface permits at least intermittent contact between the substrate and the fluid or gas. Fluids or gases contacting the surface can be stagnant or flowing, and can flow intermittently or continuously, with laminar or turbulent or mixed rheologies. A surface upon which microorganisms attach can be dry at times with sporadic fluid contact, or can have any degree of fluid exposure including total immersion. Fluid contact with the surface can take place via aerosols or other means for air-borne fluid transmission. Preferably, the surface described herein is a hard / solid and / or non-porous surface. Preferably, the surface is selected from the group consisting of a synthetic inert surface, an inorganic inert surface, and a naturally occurring surface.

[0054] The term “synthetic inert surface”, as used herein, refers to a surface that has been manufactured or otherwise created by human beings, as opposed to those occurring in nature. The word “synthetic” also means artificially put together in the context of the present invention.

[0055] The term “inorganic inert surface”, as used herein, refers to a surface that does not contain hydrocarbon as the principal element (excepting carbonates, cyanides, and cyanates), that is, matter other than plant or animal, i.e. not of biological origin.

[0056] The term “naturally occurring surface”, as used herein, refers to a surface which exists in nature, which may, however, be modified and further processed, e.g. by bleaching or washing, as long as the modification does not significantly alter the polymer backbone of the substrate.

[0057] More preferably, the

[0058] (i) synthetic inert surface is selected from the group consisting of polyester, polystyrene, polyamide (PA), polyaramid, polytetrafluorethylene (PTFE), polyethylene (PE), polypropylene (PP), polyurethane (PU), silicone, a mixture of polyurethane and polyethylenglycol (elastane), ultra-high molecular weight polyethylene (UHMWPE), high-performance polyethylene (HPPE), and melamine formaldehyde,

[0059] (ii) inorganic inert surface is selected from the group consisting of, glass, carbon, ceramic, metal, marble, granitic, quartz, concrete, and semiconductor, or

[0060] (iii) the naturally occurring surface is wood, cotton, wool, or skin.

[0061] The term “article”, as used herein, means any substrate having a surface which is prone to infestation by microorganisms. Preferably, the article has a hard / solid and / or non-porous surface. The article may be a device. More preferably, the device is selected from the group consisting of a medical device, a wet room fitting, a heating device, a ventilation device, an air condition device, a household appliance, an electronic device, and a device used in food industry.

[0062] As mentioned above, the silk polypeptide has film forming properties. After application of the disinfectant formulation, the silk polypeptide forms a film on the surface onto which the disinfectant formulation is applied. This film can also be designated as coating.

[0063] The term “coating”, as used herein, refers to any layer covering a surface. The disinfectant formulation to be coated can be in form of a liquid or an (a pressurized) aerosol. Preferably, the liquid is solution or dispersion. More preferably, the dispersion is an emulsion, a suspension, or a foam. Particularly, the coating is homogenous and continuous. More particularly, the coating has a thickness of between 1 nm and 50 pm, preferably 40 nm and 50 pm, more preferably between 0.5 pm and 10 pm and most preferably between 1.0 pm and 5 pm.

[0064] The disinfectant formulation of the present invention can be used to prevent a nosocomial infection. The term “nosocomial infection”, as used herein, refers to an infection that is acquired in a hospital or other healthcare facility. To emphasize both hospital and nonhospital settings, it is sometimes instead called a healthcare-associated infection (HAI). Such an infection can be acquired in hospital, nursing home, rehabilitation facility, outpatient clinic, diagnostic laboratory, or other clinical settings. A number of dynamic processes can bring contamination into operating rooms and other areas within nosocomial settings. Infection is spread to the susceptible patient in the clinical setting by various means. Healthcare staff also spread infection, in addition to contaminated equipment, bed linens, or air droplets. The infection can originate from the outside environment, another infected patient, staff that may be infected, or in some cases, the source of the infection cannot be determined. In some cases the microorganism originates from the patient's own skin microbiota, becoming after surgery or other procedures that compromise the protective skin barrier. Though the patient may have contracted the infection from their own skin, the infection is still considered nosocomial since it develops in the health care setting. Nosocomial infection tends to lack evidence that it was present when the patient entered the healthcare setting, thus meaning it was acquired post-admission. The nosocomial infection is preventable through guidance issued by national public health institutes such as the Centers for Disease Control and Prevention (CDC). Specifically, the disinfectant formulation of the present invention can be used for this purpose.

[0065] The term “quaternary ammonium cation”, “quaternary ammonium compound”, “quaternary ammonium salt”, “QAC”, and “quat” may be used interchangeably throughout the present disclosure to refer to ammonium compounds in which four organic groups are linked to a nitrogen atom that produces a positively charged ion (cation) of the structure NRC.

[0066] Embodiments of the invention

[0067] The present invention will now be further described. In the following passages, different aspects of the invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous, unless clearly indicated to the contrary.

[0068] A main disadvantage associated with disinfectants is that, while they can be effective at initially killing microbes, the surface is easily and quickly re-contaminated through contact, airborne microbes, and un-killed residual microbes. While some of the disinfectants would continue to offer some control if simply left on the surface, this would result in a greasy or tacky residue that would be easily negated by casual contact with the surface. Another disadvantage associated with disinfectants described in the state of the art is their short duration of action. In addition, the treated surfaces are unpleasant to touch.

[0069] Thus, there is an urgent need for disinfectants who kills microbes quickly on contact and then act as residual disinfectants, but yet do not have this undesirable sticky or tacky effect. Moreover, they should be of longer effect. Such cleaners may be useful in the home care, household, hospital care, laboratory care, medical care, or food service industry.

[0070] The present inventors generated for the first time a disinfectant formulation comprising a biocidal compound and a silk polypeptide. This formulation allows surface disinfection and has prolonged and residual biocidal properties. The disinfectant formulation comprises the biocidal compound as well as the silk polypeptide in evenly distributed form. After application of the disinfectant formulation, the silk polypeptide comprised therein forms a silk polypeptide film in which the biocidal compound is embedded or entrapped. It is, thus, shielded from its environment. As the silk polypeptide has an inherent property to film surfaces, the additional use of cross-linker or binding agents is not necessary. The silk polypeptide film remains even after drying, so that the biocidal compound persists embedded or entrapped therein. Within the silk polypeptide film, the biocidal compound retains its disinfectant property and maintains protection of the surface against microbial contamination for an extended time period after its application, preferably for at least 24 hours. Moreover, the treated surface is pleasant to touch.

[0071] Thus, in a first aspect, the present invention relates to a disinfectant formulation comprising: a biocidal compound, and a silk polypeptide.

[0072] The term “a biocidal compound” also encompasses embodiments wherein one or more biocidal compounds are comprised in / part of the disinfectant formulation. The term “a silk polypeptides” further encompasses embodiments wherein one or more (different types of) silk polypeptides are comprised in / part of the disinfectant formulation.

[0073] Especially, the biocidal compound and the silk polypeptide are (evenly) distributed in the formulation. In other words, the biocidal compound and the silk polypeptide are thoroughly mixed together.

[0074] The present inventors found that the disinfectant formulation functions as biocide. The disinfectant formulation allows surface disinfection or acts as surface disinfectant, specifically by killing (infectious) microorganisms present on the surface. The disinfectant formulation quickly kills microorganisms, specifically within between 30 seconds and 5 minutes, e.g. 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 seconds, 2, 3, 4, or 5 minutes, after application. The disinfectant formulation (after application and drying) leaves a residual protective film on the surface. Within this film the biocidal compound is entrapped, incorporated, and / or embedded. As a result, the disinfectant formulation imparts a prolonged and / or residual biocidal property.

[0075] Specifically, the disinfectant formulation of the present invention imparts a prolonged biocidal property compared to a disinfectant formulation not comprising a silk polypeptide / being free of a silk polypeptide. Preferably, the disinfectant formulation of the present invention is effective for 24 or more hours / for at least 24 hours, e.g. 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, or 72 hours, after deposition. The comparative disinfectant formulation not comprising a silk polypeptide / being free of a silk polypeptide is not as effective (see experimental section).

[0076] Alternatively or additionally, the disinfectant formulation of the present invention imparts a residual biocidal property compared to a disinfectant formulation not comprising a silk polypeptide / being free of a silk polypeptide. Preferably, the disinfectant formulation of the present invention imparts a residual biocidal property for 24 or more hours / for at least 24 hours, e.g. 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, or 72 hours, after deposition. The comparative disinfectant formulation not comprising a silk polypeptide / being free of a silk polypeptide is not as effective (see experimental section).

[0077] As mentioned above, the residual biocidal property means the achievement of at least 99.9% microbial reduction in the Environmental Protection Agency (EPA)-approved 24 hour Residual Self Sanitizing (RSS) test methodology for dried product residues on hard / solid, non- porous surfaces (EPA#01-lA). That is, the formulation as described herein displaying residual biocidal properties is able to deliver at least 99.9% microbial reduction after a 12-abrasion and 5- reinoculation 24 hour testing regime.

[0078] Cross-linking agents may be used. However, the present inventors further found that because of the film forming properties of the silk polypeptide, no additional cross-linker or binding agent is actually required. Thus, the disinfectant formulation of the present invention is preferably free of any cross-linker or binding agent. The silk polypeptide attaches to surfaces and forms films thereon without the need of any cross-linker or binding agent. This can be attributed to the capability of the silk polypeptide to perform self-assembly to / on surfaces.

[0079] In one embodiment, the biocidal compound is present in the formulation in a range of between 0.05% and 10%, e.g. 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10%, based on the weight of the disinfectant formulation, and / or the silk polypeptide is present in the formulation in a range of between 0.01% and 10% e.g. 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10%, based on the weight of the disinfectant formulation.

[0080] In one preferred embodiment, the biocidal compound is selected from the group consisting of a quaternary ammonium compound, citric acid, sulfamic acid, glycolic acid, lactic acid, lauric acid, capric acid, silane quaternary salts, triclosan, zinc pyrithione, metal salt, metal oxide, phenol, botanical, halogen, peroxide, heterocyclic antimicrobial, an aldehyde, and an alcohol, or is a combination thereof.

[0081] Particularly, the quaternary ammonium compound has a structure of:

[0082] (Formula I) wherein

[0083] Ri is alkyl, alkoxy, or aryl, either with or without heteroatoms, or saturated or non- saturated, R2 is alkyl, alkoxy, or aryl, either with or without heteroatoms, or saturated or non- saturated, R3 is alkyl, alkoxy, or aryl, either with or without heteroatoms, or saturated or non- saturated, R4 is alkyl, alkoxy, or aryl, either with or without heteroatoms, or saturated or non- saturated, X", an anion, is halogen, sulfonate, sulfate, phosphonate, phosphate, carbonate, bicarbonate, hydroxy, or carboxylate.

[0084] More particularly, the quaternary ammonium compound is selected from the group consisting of n-alkyl dimethyl benzyl ammonium chloride, di-n-octyl dimethyl ammonium chloride, dodecyl dimethyl ammonium chloride, n-alkyl dimethyl benzyl ammonium saccharinate, 3-(trimethoxysilyl)propyldimethyloctadecyl ammonium chloride, and a combination thereof.

[0085] Even more particularly, the quaternary ammonium compound is Decyl dimetthyl ammonium chloride, Di-Decyl Dimethyl Ammonium Chloride, or N-Alkyl-Dimethyl Benzyl Ammonium Chloride.

[0086] Alternatively, the quaternary ammonium compound is a polymeric version having a structure of:

[0087] (Formula II) wherein

[0088] Ri is hydrogen, methyl, ethyl, propyl or other carbon alkyl group,

[0089] R2 is hydrogen, methyl, ethyl, propyl or other carbon alkyl group,

[0090] R3 is methylene, ethylene, propylene or other alkylene linking group,

[0091] R4 is methylene, ethylene, propylene or other alkylene linking group,

[0092] Rs is hydrogen, methyl, ethyl, propyl or other carbon alkyl group,

[0093] Re is hydrogen, methyl, ethyl, propyl or other carbon alkyl group, and n is in a range of 2 to 10,000.

[0094] More particularly, the polymeric version is a cationic polymer.

[0095] Even more particularly, the cationic polymer is a polyamine derived from dimethylamine and epichlorohydrin.

[0096] Alternatively, the quaternary ammonium compound is poly diallyldimethylammonium chloride, polyDADMAC, or a compound comprising a biguanide moiety in the molecule.

[0097] A water soluble or dispersible biocidal compound is preferred, although biocides soluble in alcohol may be alternatively employed.

[0098] Preferably, the silk polypeptide, as used herein, is a recombinant silk polypeptide.

[0099] It is particularly preferred that the (recombinant) silk polypeptide is a polypeptide with an amino acid sequence which comprises or consists of at least 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95% multiple copies of repetitive units. Said repetitive units may be identical or different.

[0100] It is further particularly preferred that the (recombinant) silk polypeptide consists of between 40 to 4000 amino acids. For example, the (recombinant) silk polypeptide consists of between 100 to 3500 amino acids, between 200 to 2500 amino acids, or between 250 to 2000 amino acids.

[0101] It is also particularly preferred that the (recombinant) silk polypeptide comprises or consists of (at least two identical) repetitive units. For example, the (recombinant) silk polypeptide may comprise between 2 to 100 repetitive units, e.g. 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,

[0102] 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,

[0103] 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,

[0104] 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,

[0105] 95, 96, 97, 98, 99, or 100 repetitive units. It is particularly more preferred that the repetitive units are independently selected from the group consisting of module C having an amino acid sequence according to SEQ ID NO: 1 or variants thereof, module CCyshaving an amino acid sequence according to SEQ ID NO: 2 or variants thereof, and module CLyshaving an amino acid sequence according to SEQ ID NO: 3 or variants thereof.

[0106] The 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, or 10, 11, 12, 13, 14, or 15 amino acid changes in the amino acid sequence (i.e. substitutions, additions, insertions, deletions, N-terminal truncations and / or C-terminal truncations). Such a module variant can alternatively or additionally be characterized by a certain degree of sequence identity to the reference module from which it is derived. Thus, the module C variant has a sequence identity of at least 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,

[0107] 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,

[0108] 91, 92, 93, 94, 95, 96, 97, 98, 99% or even 99.9% to the respective reference module C.

[0109] Preferably, the sequence identity is over a continuous stretch of at least 5, 10, 15, 18, 20, 24, 27,

[0110] 28, 30, 34, or more amino acids, preferably over the whole length of the respective reference module C.

[0111] The sequence identity may be at least 80% over the whole length, may be at least 85% over the whole length, may be at least 90% over the whole length, may be at least 95% over the whole length, may be at least 98% over the whole length, or may be at least 99% over the whole length of the respective reference module C. Alternatively, the sequence identity may be at least 80% over a continuous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids, may be at least 85% over a continuous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids, may be at least 90% over a continuous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids, may be at least 95% over a continuous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids, may be at least 98% over a continuous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids, or may be at least 99% over a continuous stretch of at least 5, 10, 15, 18, 20, 24, 28, or 30 amino acids of the respective reference module C.

[0112] A fragment (or deletion) variant of module C has preferably a deletion of up to 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 amino acids at its N-terminus and / or at its C-terminus. The deletion can also be internally.

[0113] Additionally, the module C variant or fragment is only regarded as a module C variant or fragment within the context of the present invention, if the modifications with respect to the amino acid sequence on which the variant or fragment is based do not negatively affect the ability of the silk polypeptide to entrap or embed the biocidal compound. The skilled person can readily assess whether the silk polypeptide comprising a module C variant or fragment still has this property. In this respect, it is referred to the examples comprised in the experimental part of the present patent application.

[0114] Module CCysor CLysvariants may also be encompassed by the present invention. Regarding the module CCysor CLysvariants, the same explanations / definitions apply which have been made with respect to the module C variant (see above).

[0115] It is particularly even more preferred that the silk polypeptide comprises (C)m, (C)mCCys, (C)mCLys, CCys(C)m, CLys(C)m, (CCys)m, or (CLys)m, wherein m is an integer of 2 to 96, 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, 29, 30,

[0116] 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,

[0117] 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,

[0118] 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, or 96.

[0119] It is particularly most preferred that the silk polypeptide comprises C2, C4, Ce, C8, Ci6, C32, C48, (C)2CCys, (C)4CCys, (C)6CCys, (C)8CCys, (C)i6CCys, (C)32CCys, (C)48CCys, (C)2CLys, (C)4CLys, (C)6CLys, (C)8CLys, (C)i6CLys, (C)32CLys, (C)48CLys, CCys(C)2, CCys(C)4, CCys(C)6, CCys(C)8, CCys(C)i6, CCys(C)32, CCys(C)48, CLys(C)2, CLys(C)4, CLys(C)6, CLys(C)8, CLys(C)i6, CLys(C)32, CLyS(C)48, CCyS2, CCyS4, CCyS6, CCyS8, CCyS16, CCyS32, CCyS48, CLyS2, CLyS4, CLyS6, CLyS8, CLyS16, CLyS32, or CLys48.

[0120] The silk polypeptide C8has the amino acid sequence according to SEQ ID NO: 4 (8 times module C), the silk polypeptide Ci6 (16 times module C) has the amino acid sequence according to SEQ ID NO: 5, the silk polypeptide C32 (32 times module C) has the amino acid sequence according to SEQ ID NO: 6, and the silk polypeptide C48(48 times module C) has the amino acid sequence according to SEQ ID NO: 7.

[0121] The above-described silk polypeptide preferably consists exclusively of repetitive units. In other words, the silk polypeptide preferably does not comprise / is free of non-repetitive units.

[0122] The only component that can additionally be present as part of the silk polypeptide is a tag or moiety, e.g. allowing easy transcription of said silk polypeptide in expression systems and / or allowing easy isolation of said silk polypeptide from the expression systems. Said tag may be an his tag or a flag tag.

[0123] More preferably, the (recombinant) silk polypeptide is a (recombinant) spider silk polypeptide, e.g. 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.

[0124] In one more preferred embodiment, the formulation is in form of a liquid or an (a pressurized) aerosol. Particularly, the liquid is a solution or dispersion. More particularly, the dispersion is an emulsion, a suspension, or a foam. The disinfectant formulation of the present invention may be provided as concentrated liquid, e.g. concentrated solution, (i.e. as a “concentrate”) or as a ready-to-use (i.e. an “RTU”) liquid, e.g. solution, either of which may be applied to a surface to be treated, e.g. a solid / hard surface, using known application means. Some exemplary disinfectant formulations in liquid form, such as in solution form, may be applied to a woven or non-woven substrate to make a wipe, wherein the wipe is used to apply the disinfectant formulation to a surface to be treated with the formulation. An advantage of using a wipe is that it may be disposed of after use, such that it will not be reused to apply the formulation to more than one surface.

[0125] For example, the formulation is in form of a liquid and the biocidal compound is present in the liquid in a range of between 0.05% and 10%, e.g. 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10%, based on the weight of the disinfectant formulation, and / or the silk polypeptide is present in the liquid in a range of between 0.01% and 10% e.g. 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10%, based on the weight of the disinfectant formulation.

[0126] In one even more preferred embodiment, the formulation further comprises a carrier.

[0127] Particularly, the carrier comprises one or more solvents (i.e. mixture of solvents). Any solvent that is volatile and allows easy evaporation at ambient condition may be used.

[0128] More particularly, the one or more solvents are selected from the group consisting of an aqueous solution, preferably water or a buffered aqueous solution, a low molecular weight alcohol, an alkylene glycol ether, a terpene, and a terpene derivative.

[0129] Even more particularly,

[0130] (i) the low molecular weight alcohol is selected from the group consisting of ethanol, isopropyl alcohol, butanol, and pentanol, or is a combination thereof,

[0131] (ii) the alkylene glycol ether is selected from the group consisting of ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene clycol monohexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, propylene glycol methyl ether, propylene glycol methyl ether acetate, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, dipropylene glycol methyl ether, dipropylene glycol methyl ether acetate, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, and tripropylene glycol methyl ether, or is a combination thereof, and / or (iii) the terpene is selected form the group consisting of a terpene alcohol, terpene ester, terpene ether, and terpene aldehyde, or is a combination thereof.

[0132] A preferred carrier in a liquid formulation for a home care cleaning application is water.

[0133] As mentioned above, either a single solvent or a mixture of solvents can be part of the disinfectant formulation. The types of solvents used for the disinfectant formulation may depend upon the intended uses of the disinfectant formulation.

[0134] For example, if the formulation of the present invent is intended for home care use, cleaning the contaminated surfaces free of all types of dirt or soil may be of primary interest. Liquid carrier or media that assist and enhance the removal of soil may be part of formulation. For example, the disinfectant formulation may desire to include alkyl or multi-alkyl glycol ethers for better cleaning performance in the home care version of the formulation. On the other hand, if the primary goal of the disinfectant formulation is to be used at a health care facility where the major concern is hospital acquired infection, then quick drying of the liquid formulation may be more desirable than cleaning dirt or soil out of the surfaces. Low molecular weight alcohols should be considered to help the liquid formulation to dry fast after the application. Also, a low molecular weight alcohol in the liquid formulation will strengthen the sanitizing activity of the liquid formulation.

[0135] For health care use of the disinfectant formulation, a mixture of water and low molecular weight alcohol is preferred. The amount of alcohol present in the liquid formulation is preferred to be at such a level that the liquid formulation is capable of forming a zerotropic mixture between the alcohol and water. A minimum amount of alcohol, if present, in the liquid formulation is 10%. Preferably, for health care use of the residual disinfectant, the alcohol concentration is 30%, and most preferably the alcohol concentration is at least 50% based on the weight of liquid formulation for the health care use of the formulation.

[0136] In one still even more preferred embodiment the disinfectant formulation further comprises a surfactant or a wetting agent, a pH adjusting agent, and / or one or more additional components components selected from the group consisting of a corrosion inhibitor, chelant, compatibilizer, coupling agent, corrosion inhibitor, rheology modifier, fragrance, colorant, preservative, an UV stabilizer, an optical brightener, and an active ingredient indicator.

[0137] The term “a surfactant” encompasses embodiments wherein one or more surfactants are comprised in / part of the disinfectant formulation. The term “a wetting agent” also encompasses embodiments wherein one or more wetting agents are comprised in / part of the disinfectant formulation. The term “a pH adjusting agent” further encompasses embodiments wherein one or more pH adjusting agents are comprised in / part of the disinfectant formulation.

[0138] As mentioned above, a surfactant or wetting agent may be employed. The surfactant assists the (liquid) formulation to spread and evenly coat the surface being treated. The surfactant additionally contributes to the formation of a zeotropic mixture between alcohol and water, thus, facilitating a rapid and uniform drying of the (liquid) formulation once being applied onto a surface. A surfactant also plays an important role in the disinfectant (liquid) formulation of the present invention for home care use if the soil cleaning performance is the key feature the product is designed to possess.

[0139] The surfactant may be present in a range of between 0.01% and 10%, e.g. 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10%. Specifically, the surfactant is nonionic, anionic, or amphoteric in nature.

[0140] There is no limitation on the types of pH adjusting agents that can be added. The pH adjusting agent may be selected from the group consisting of triethanolamine, diethanolamine, monoethanolamine, sodium hydroxide, sodium carbonate, potassium hydroxide, potassium carbonate, calcium carbonate, citric acid, acetic acid, hydrochloric acid, sulfamic acid, and sulfuric acid, or is a combination thereof.

[0141] The presence of a pH adjusting agent depends on the targeted uses. A liquid formulation for home care use may need an appropriate pH condition. For example, if the liquid formulation is used in the kitchen area, a high pH product may be desired in order to effectively remove grease soils commonly found in the area. If the product is used in the bathroom area, soap scum and hard water deposits may be the primary concern. In such case, a low pH product may be more appropriate for such a purpose.

[0142] Specifically, the disinfectant formulation comprises a biocidal compound selected from the group consisting of a quaternary ammonium compound, citric acid, sulfamic acid, glycolic acid, lactic acid, lauric acid, capric acid, silane quaternary salts, triclosan, zinc pyrithione, metal salt, metal oxide, phenol, botanical, halogen, peroxide, heterocyclic antimicrobial, an aldehyde, and an alcohol, and a spider silk polypeptide.

[0143] More specifically, the disinfectant formulation is in form of a liquid or an (a pressurized) aerosol and comprises a biocidal compound selected from the group consisting of a quaternary ammonium compound, citric acid, sulfamic acid, glycolic acid, lactic acid, lauric acid, capric acid, silane quaternary salts, triclosan, zinc pyrithione, metal salt, metal oxide, phenol, botanical, halogen, peroxide, heterocyclic antimicrobial, an aldehyde, and an alcohol, a spider silk polypeptide, and a solvent.

[0144] Even more specifically, the disinfectant formulation is in form of a liquid or an (a pressurized) aerosol and comprises a quaternary ammonium compound a spider silk polypeptide, water (solvent), and mono propylene glycol (additional solvent).

[0145] Still even more specifically, the disinfectant formulation is in form of a liquid or an (a pressurized) aerosol and comprises a biocidal compound, a silk polypeptide, water (solvent), mono propylene glycol (additional solvent), a surfactant, a chelant, an acidic buffering system (pH adjusting agent), a fragrance, and a colorant.

[0146] For example, the disinfectant formulation is in form of a liquid and comprises a biocidal compound, a spider silk polypeptide, water (solvent), mono propylene glycol (additional solvent), non-ionic C12-C14-7 EO (surfactant), GLDA (a chelant), Na Citrate (pH adjusting agent), a fragrance, and a colorant.

[0147] As biocidal compound, a quaternary ammonium compound is preferably used. The use of different quaternary ammonium compounds is exemplarily shown in the experimental section. For example, the disinfectant formulation is in form of a liquid and comprises decyl dimetthyl ammonium chloride, a spider silk polypeptide, C12-C14 EO7, C9-C11 EO5, trethanolamine, and Citric Acid.

[0148] For example, the disinfectant formulation is in form of a liquid and comprises di-decyl dimethyl ammonium chloride, a silk polypeptide, C12-C14 EO7, C9-C11 EO5, trethanolamine, and Citric Acid.

[0149] For example, the disinfectant formulation is in form of a liquid and comprises N-alkyl-dimethyl benzyl ammonium chloride, a silk polypeptide, C12-C14 EO7, C9-C11 EO5, trethanolamine, and Citric Acid.

[0150] When the formulation is in form of a pressurized aerosol, it is preferred that the formulation further comprises a propellant. The propellant may be selected from the group consisting of Cl to CIO hydrocarbons or halogenated hydrocarbons, compressed air, nitrogen, and carbon dioxide. Alternatively, a bag on valve package may be used to aerosol the product without directly adding a propellant to the formulation.

[0151] The formulation, specifically the liquid formulation, as described above can be made or mixed by any conventional method known to a skilled person. There are no preferred addition procedures for the formulation provided that the formulation is ultimately homogeneous, compatible and stable. For example, if the biocidal compound and / or the silk polypeptide is a solid or powder, it may be preferable to first dissolve or disperse the biocidal compound and / or silk polypeptide in a carrier such as water or alcohol to make a stock solution or dispersion. The stock liquid solution or dispersion may be readily added into the formulation during the mixing procedure.

[0152] As mentioned above, the disinfectant formulation can be applied to surfaces, preferably hard / solid and / or non-porous surfaces, to disinfect them.

[0153] The surface may be a surface in health care or hospital settings. In addition to hand disinfection, surface disinfection is, for example, one of the most important measures in health care or hospital settings to limit the transmission of pathogens. Surfaces in the immediate patient surroundings and high-touch surfaces with frequent hand or skin contact must be disinfected routinely. When disinfecting surfaces, it is important to observe some rules such as the correct dosage, complete wetting and exposure times, otherwise the disinfection may be less effective. The correct choice of the biocidal compound is also relevant.

[0154] Surface disinfection has gained much importance in infection prophylaxis. Studies confirm: clinically relevant pathogens often can persist on surfaces for weeks or months - cross contamination poses a permanent risk. Surfaces that come into contact with hands and skin frequently as well as areas that most likely become contaminated should be disinfected daily. For surface disinfection in hospitals, the Commission for Hospital Hygiene and Infection Prevention at the Robert Koch-Institute (RKI) classified risk areas and specified indications that are incorporated into the hygiene plan in accordance with the conditions and requirements in the individual hospitals.

[0155] The surface may also be a surface with contact to food / associated with food preparation, a household surface, a surface associated in a medical laboratory, a surface in the institutional and hospitality environment, a lavatory fixture, a lavatory appliance, a wall, and a flooring surface.

[0156] In a second aspect, the present invention relates to a method of disinfecting a surface comprising the steps of:

[0157] (i) providing a disinfectant formulation according to the first aspect, and

[0158] (ii) applying the disinfectant formulation to / onto a surface, thereby disinfecting the surface.

[0159] In another embodiment, the method further comprises the step of:

[0160] (iii) drying the surface.

[0161] In this embodiment, the method of disinfecting a surface comprising the steps of:

[0162] (i) providing a disinfectant formulation according to the first aspect,

[0163] (ii) applying the disinfectant formulation to / onto a surface, and (iii) drying the surface.

[0164] Specifically, the biocidal compound and the silk polypeptide are (evenly) distributed in the formulation. In other words, the biocidal compound and the silk polypeptide are thoroughly mixed together.

[0165] The present inventors found that the disinfectant formulation functions as biocide. The disinfectant formulation allows surface disinfection or acts as surface disinfectant, specifically by killing (infectious) microorganisms present on the surface. The disinfectant formulation quickly kills microorganisms, specifically within between 30 seconds and 5 minutes, e.g. 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 seconds, 2, 3, 4, or 5 minutes, after application.

[0166] More specifically, the application of the disinfectant formulation results in a film on the surface / coats the surface. After application of the formulation, the biocidal compound is embedded within or entrapped by the silk polypeptide. In other words, after application of the formulation, a silk polypeptide film is formed in which the biocidal compound is embedded or entrapped. Even after drying, the disinfectant formulation leaves a residual protective film on the surface. As a result, the disinfectant formulation imparts a prolonged and / or residual biocidal property.

[0167] As mentioned above, the residual biocidal property means the achievement of at least 99.9% microbial reduction in the Environmental Protection Agency (EPA)-approved 24 hour Residual Self Sanitizing (RSS) test methodology for dried product residues on hard / solid, non- porous surfaces (EPA#01-lA). That is, the formulation as described herein displaying residual biocidal properties is able to deliver at least 99.9% microbial reduction after a 12-abrasion and 5- reinoculation 24 hour testing regime. In this respect, it is also referred to the first aspect of the present invention.

[0168] The present inventors further found that because of the film forming properties of the silk polypeptide, no additional cross-linker or binding agent is required. Thus, the disinfectant formulation of the present invention is free of any cross-linker or binding agent. The silk polypeptide attaches to surfaces and forms films thereon without the need of any cross-linker or binding agent. This can be attributed to the capability of the silk polypeptide to perform selfassembly to / on surfaces.

[0169] It is preferred that the formulation is in form of a liquid or an (a pressurized) aerosol. Particularly, the liquid is a solution or dispersion. More particularly, the dispersion is an emulsion, a suspension, or a foam. It is within the scope of the present invention that wipe products can also be made comprising or pre-treated with the disinfectant formulation as described herein, for example, for off-the-shelf sale or use.

[0170] There are a variety of ways to apply the disinfectant formulation to surfaces, depending on the type of biocidal compound, the surface being disinfected, and / or the desired outcome.

[0171] The disinfectant formulation may be applied by a variety of means. It is more preferred that the application of the disinfectant formulation takes place via spraying, fogging, rolling, brushing, immersing, mopping, wiping, or via a combination thereof. Some of the most common methods include:

[0172] Wiping: This is a simple and effective way to apply the disinfectant formulation to surfaces. A clean cloth or sponge can be soaked in the disinfectant formulation and then used to wipe down the surface. Care should be taken to reach all areas of the surface, including any cracks or crevices.

[0173] An exemplary method of use of a wipe may comprise: removing the wipe from a pouch or container; applying the wipe to a hard / solid surface to be treated; wiping the wipe across the hard / solid surface, expressing the disinfectant formulation from the wipe onto the hard / solid surface; and allowing the disinfectant formulation to remain on the surface.

[0174] Spraying: The disinfectant formulation can also be sprayed onto surfaces. This is a good option for large areas or for surfaces that are difficult to reach with a cloth. When spraying the disinfectant formulation, it is important to follow the manufacturer's instructions and to wear appropriate personal protective equipment (PPE), such as gloves and eye protection. Too wet formulations may subsequently be wiped dry with a dry cloth or paper towel.

[0175] If sprayed, the liquid formulation advantageously may be supplied in a conventional bottle with a sprayer. The sprayer can be a trigger sprayer or a hand pump bottle sprayer.

[0176] As an option to a liquid sprayer, an aerosol sprayer may be used to deliver the liquid formulation to / onto surfaces. An aerosol sprayer is a type of dispensing system which creates an aerosol mist of liquid particles. It comprises a can or bottle that contains a payload, and usually a propellant under pressure. When the sprayer’s valve is opened, the payload is forced out of a small opening and emerges as an aerosol or mist. Alternatively, a bag on valve package may be used to aerosol the product without directly adding a propellant to the formulation.

[0177] Electrostatic spraying: Electrostatic spraying is a newer method of applying the disinfectant formulation that is becoming increasingly popular. This method uses an electrostatic charge to attract the disinfectant particles to the surface being disinfected. This results in a more uniform coverage of the disinfectant formulation and can help to reduce the amount of disinfectant needed. Fogging: Fogging is a method of applying the disinfectant formulation to surfaces in a fine mist. This is a good option for large areas or for areas that are difficult to reach with other methods.

[0178] Foggers are sprayers that apply the disinfectant formulation to large surface areas. They depend on getting enough of the disinfectant formulation into the air that gravity pulls it down to coat surfaces with the formulation Application may be uneven and contact time may not be long enough to kill germs. Surfaces must also be cleaned before they can be fogged, a step that is often overlooked. Fogging can be done with a manual or electric fogger.

[0179] Immersion: This method is used to disinfect small objects that can be submerged in the disinfectant formulation. The objects should be soaked in the solution for the amount of time specified by the manufacturer.

[0180] In addition to these general methods, there are also a number of specialized methods for applying the disinfectant formulation to certain types of surfaces. For example, disinfecting wipes are often used to disinfect medical equipment and surfaces in healthcare settings. And, ultraviolet light (UV-C) can be used, in addition to the disinfectant formulation, to disinfect surfaces in food processing plants and other industrial settings.

[0181] When choosing a method for applying disinfectant, it is important to consider the following factors:

[0182] The type of disinfectant being used. Some disinfectants are more effective when applied in a certain way.

[0183] The surface being disinfected. Different surfaces may have different requirements for cleaning and disinfection.

[0184] The desired outcome. Do you need to disinfect the surface to kill a specific type of pathogen? Or, do you simply need to reduce the overall number of bacteria on the surface?

[0185] Some exemplary methods further comprise allowing the hard / solid surface to dry, whereas other exemplary methods further comprise drying the surface, e.g. by wiping the hard surface with a dry wipe or wiping device.

[0186] When an exemplary disinfectant formulation is applied to a hard / solid surface using any of the means described above (e.g. including, but not limited to, by spraying (a non-limiting example of spraying includes spraying an aerosolized disinfectant formulation), by foaming, by fogging, by soaking, by dipping, or by wiping), disinfection of the surface is preferably achieved in a period of time of between 30 seconds and 5 minutes, e.g. 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 seconds, 2, 3, 4, or 5 minutes, after application. Thus, in one preferred embodiment of the second aspect, the present invention relates to a method of disinfecting a surface comprising the steps of

[0187] (i) providing a liquid disinfectant formulation according to the first aspect, and

[0188] (ii) applying the liquid disinfectant formulation to / onto a surface.

[0189] In one another preferred embodiment of the second aspect, the present invention relates to a method of disinfecting a surface comprising the steps of

[0190] (i) providing a liquid disinfectant formulation according to the first aspect,

[0191] (ii) applying the liquid disinfectant formulation to / onto a surface, and

[0192] (iii) drying the surface.

[0193] The application of the disinfectant formulation can take place via spraying, fogging, rolling, brushing, mopping, wiping, immersing, or via a combination thereof.

[0194] Different forms of drying are possible. For example, the formulation may be, after its application, wiped dry, e.g. with a dry cloth or paper towel. The formulation can also be left to dry under ambient conditions.

[0195] Sometimes, the drying step is necessary. In other cases, the drying step is superfluous. This depends on the components which are part of the formulation, e.g. on the solvents or surfactants used. Some components of the formulation, e.g. solvents or surfactants, evaporate quickly others slowly.

[0196] For example, if the primary goal of the disinfectant formulation is to be used at a health care facility where the major concern is hospital acquired infection, then quick drying of the liquid formulation is highly desirable. Low molecular weight alcohols should be considered to help the liquid formulation to invent dry fast after its application. In addition, the presence of a surfactant may also accelerate the drying of the formulation after its application. Particularly, a surfactant additionally contributes to the formation of a zeotropic mixture between alcohol and water, thus, facilitating a rapid and uniform drying of the liquid formulation once being applied onto a surface.

[0197] The surface to which the disinfectant formulation of the first aspect is applied is preferably a solid and / or non-porous surface.

[0198] Specifically, the surface is a surface with contact to food / associated with food preparation, a household surface, a surface in a health care environment, a surface associated with hospital environments, a surface associated in a medical laboratory, a surface in a medical treatment environment, a surface in the institutional and hospitality environment, a lavatory fixture, a lavatory appliance, a wall, and a flooring surface. In this respect, it is also referred to the first aspect of the present invention. Alternatively or additionally, the surface is selected from the group consisting of a synthetic inert surface, an inorganic inert surface, and a naturally occurring surface.

[0199] More specifically, the

[0200] (i) synthetic inert surface is selected from the group consisting of polyester, polystyrene, polyamide (PA), polyaramid, polytetrafluorethylene (PTFE), polyethylene (PE), polypropylene (PP), polyurethane (PU), silicone, a mixture of polyurethane and polyethylenglycol (elastane), ultra-high molecular weight polyethylene (UHMWPE), high-performance polyethylene (HPPE), and melamine formaldehyde,

[0201] (ii) inorganic inert surface is selected from the group consisting of, glass, carbon, ceramic, metal, marble, granitic, quartz, concrete, and semiconductor, or

[0202] (iii) the naturally occurring surface is wood, cotton, wool, or skin.

[0203] The surface may be the surface / part of an article.

[0204] Specifically, the article is a device. More specifically, the device is selected from the group consisting of a medical device, a wet room fitting, a heating device, a ventilation device, an air condition device, a household appliance, an electronic device, and a device used in food industry.

[0205] In a third aspect, the present invention relates to an article coated on its surface with or comprising on its surface the disinfectant formulation according to the first aspect.

[0206] The invention also relates to an article treated with the disinfectant formulation according to the first aspect.

[0207] Specifically, the article is a device. More specifically, the device is selected from the group consisting of a medical device, a wet room fitting, a heating device, a ventilation device, an air condition device, a household appliance, an electronic device, and a device used in food industry.

[0208] In a fourth aspect, the present invention relates to the use of the disinfectant formulation according to the first aspect to disinfect a surface.

[0209] The surface is preferably a solid and / or non-porous surface.

[0210] Specifically, the surface is a surface with contact to food / associated with food preparation, a household surface, a surface in a health care environment, a surface associated with hospital environments, a surface associated in a medical laboratory, a surface in a medical treatment environment, a surface in the institutional and hospitality environment, a lavatory fixture, a lavatory appliance, a wall, and a flooring surface. In this respect, it is also referred to the first aspect of the present invention.

[0211] Alternatively or additionally, the surface is selected from the group consisting of a synthetic inert surface, an inorganic inert surface, and a naturally occurring surface. More specifically, the

[0212] (i) synthetic inert surface is selected from the group consisting of polyester, polystyrene, polyamide (PA), polyaramid, polytetrafluorethylene (PTFE), polyethylene (PE), polypropylene (PP), polyurethane (PU), silicone, a mixture of polyurethane and polyethylenglycol (elastane), ultra-high molecular weight polyethylene (UHMWPE), high-performance polyethylene (HPPE), and melamine formaldehyde,

[0213] (ii) inorganic inert surface is selected from the group consisting of, glass, carbon, ceramic, metal, marble, granitic, quartz, concrete, and semiconductor, or

[0214] (iii) the naturally occurring surface is wood.

[0215] The surface may be the surface / part of an article.

[0216] Specifically, the article is a device. More specifically, the device is selected from the group consisting of a medical device, a wet room fitting, a heating device, a ventilation device, an air condition device, a household appliance, an electronic device, and a device used in food industry.

[0217] For this purpose, the disinfectant formulation may be part of / comprised in a household cleaner, disinfectant, sanitizer, or wet wipe.

[0218] The disinfectant formulation may be provided as concentrated liquid, e.g. concentrated solution, (i.e. as a “concentrate”) or as a ready-to-use (i.e. an “RTU”) liquid, e.g. solution, either of which may be applied to a surface to be treated, e.g. a solid / hard surface, using known application means. If the disinfectant formulation of the present invention is provided as concentrated liquid, e.g. concentrated solution, (i.e. as a “concentrate”), it has to be first diluted before use., e.g. with a solvent such as water. Some exemplary disinfectant formulations in liquid form, such as in solution form, may be applied to a woven or non-woven substrate to make a wipe, wherein the wipe is used to apply the disinfectant formulation to a surface to be treated with the formulation. An advantage of using a wipe is that it may be disposed of after use, such that it will not be reused to apply the formulation to more than one surface.

[0219] In a fifth aspect, the present invention relates to the use of the disinfectant formulation according to the first aspect as disinfectant for home care, household, hospital care, laboratory care, medical care, or food service industry.

[0220] For this purpose, the disinfectant formulation may be part of / comprised in a household cleaner, disinfectant, sanitizer, or wet wipe.

[0221] The disinfectant formulation may be provided as concentrated liquid, e.g. concentrated solution, (i.e. as a “concentrate”) or as a ready-to-use (i.e. an “RTU”) liquid, e.g. solution, either of which may be applied to a surface to be treated, e.g. a solid / hard surface, using known application means. If the disinfectant formulation of the present invention is provided as concentrated liquid, e.g. concentrated solution, (i.e. as a “concentrate”), it has to be first diluted before use., e.g. with a solvent such as water. Some exemplary disinfectant formulations in liquid form, such as in solution form, may be applied to a woven or non-woven substrate to make a wipe, wherein the wipe is used to apply the disinfectant formulation to a surface to be treated with the formulation. An advantage of using a wipe is that it may be disposed of after use, such that it will not be reused to apply the formulation to more than one surface.

[0222] In a sixth aspect, the present invention relates to an apparatus / a device comprising the disinfectant formulation according to the first aspect.

[0223] There are a variety of apparatuses / devices that allow for the application of the disinfectant formulation according to the first aspect. Preferably, the apparatus / device is selected from the group consisting of a spray bottle, a trigger sprayer, a backpack sprayer, an electrostatic sprayer of a wipe.

[0224] Some of the preferred apparatuses / devices include:

[0225] Spray bottles: Spray bottles are a simple and effective way to apply disinfectants to surfaces. They are available in a variety of sizes and can be used to apply a variety of disinfectants, including liquids, foams, and gels.

[0226] Trigger sprayers: Trigger sprayers are similar to spray bottles, but they have a larger capacity and can deliver a more powerful spray. This makes them ideal for disinfecting large areas or for surfaces that are difficult to reach with a spray bottle.

[0227] Backpack sprayers: Backpack sprayers are even larger than trigger sprayers and can be used to disinfect very large areas. They are often used in commercial settings, such as hospitals and restaurants.

[0228] Electrostatic sprayers: Electrostatic sprayers use an electrical charge to attract the disinfectant particles to the surface being disinfected. This results in a more uniform coverage of the disinfectant and can help to reduce the amount of disinfectant needed. Electrostatic sprayers are often used in healthcare settings and other critical environments.

[0229] Disinfecting wipes: Disinfecting wipes are pre-moistened wipes that contain a disinfectant solution. They are convenient to use and can be used to disinfect a variety of surfaces.

[0230] When choosing an apparatus / a device for applying the disinfectant formation, it is important to consider the following factors:

[0231] The type of biocidal compound being used. Some devices are not compatible with all types of biocidal compounds.

[0232] The surface being disinfected. Different surfaces may have different requirements for cleaning and disinfection. The desired outcome. Do you need to disinfect the surface to kill a specific type of pathogen? Or, do you simply need to reduce the overall number of bacteria on the surface?

[0233] In a seventh aspect, the present invention relates to a kit comprising the disinfectant formulation according to the first aspect, or the apparatus according to the sixth aspect.

[0234] In one embodiment, the kit comprises the disinfectant formulation according to the first aspect.

[0235] In this case, the kit preferably further comprises the following items: an application device, a personal protective equipment (PPE), and / or instructions.

[0236] As to the application device: The application device is the device used to apply the disinfectant to surfaces. Some common application devices include spray bottles, trigger sprayers, backpack sprayers, electrostatic sprayers, and disinfecting wipes.

[0237] As to the personal protective equipment (PPE): PPE is used to protect the user from exposure to the disinfectant. Some common PPE items include gloves, eye protection, and respirators.

[0238] As to the instructions: The instructions encompass information on how to use the disinfectant formulation and application device safely and effectively.

[0239] Some kits may also include additional items, such as: cleaning supplies, storage container, and / or carrying device.

[0240] As to the cleaning supplies: Cleaning supplies may be included in the kit if the disinfectant formulation needs to be mixed with a solvent such as water for dilution or if the surface needs to be cleaned before it is disinfected.

[0241] For example, the disinfectant formulation of the present invention may be provided as concentrated liquid, e.g. concentrated solution, (i.e. as a “concentrate”) or as a ready-to-use (i.e. an “RTU”) liquid, e.g. solution, either of which may be applied to a surface to be treated, e.g. a solid / hard surface, using known application means. Some exemplary disinfectant formulations in liquid form, such as in solution form, may be applied to a woven or non-woven substrate to make a wipe, wherein the wipe is used to apply the disinfectant formulation to a surface to be treated with the formulation. An advantage of using a wipe is that it may be disposed of after use, such that it will not be reused to apply the formulation to more than one surface.

[0242] As to the storage container: A storage container may be included in the kit to store the disinfectant and application device when they are not in use.

[0243] As to the carrying case: A carrying case may be included in the kit to make it easy to transport the kit from one location to another.

[0244] In one exemplarily embodiment, the kit comprises the disinfectant formulation according to the first aspect in a ready-to-use format, and a storage container and / or carrying case.

[0245] In one another exemplarily embodiment, the kit comprises the disinfectant formulation according to the first aspect as concentrate, a solvent such as water or an alcohol for diluting the concentrate to generate a ready-to-use formulation, and a storage container and / or carrying case.

[0246] In one further exemplarily embodiment, the kit comprises the disinfectant formulation according to the first aspect in a ready-to-use format, an application device, a storage container for the disinfectant formulation and the application device, and optionally a carrying case.

[0247] Some common application devices include spray bottles, trigger sprayers, backpack sprayers, electrostatic sprayers, and disinfecting wipes.

[0248] In one another embodiment, the kit comprises the apparatus according to the sixth aspect.

[0249] This apparatus, in turn, comprises the disinfectant formulation according to the first aspect.

[0250] In this case, the kit preferably further comprises the following items: a personal protective equipment (PPE) and / or instructions.

[0251] As to the personal protective equipment (PPE): PPE is used to protect the user from exposure to the disinfectant. Some common PPE items include gloves, eye protection, and respirators.

[0252] As to the instructions: The instructions encompass information on how to use the disinfectant formulation and application device safely and effectively.

[0253] Some kits may also include additional items, such as: cleaning supplies, storage container, and / or carrying device.

[0254] As to the cleaning supplies: Cleaning supplies may be included in the kit if the surface needs to be cleaned before it is disinfected.

[0255] As to the storage container: A storage container may be included in the kit to store the apparatus when it is not in use.

[0256] As to the carrying case: A carrying case may be included in the kit to make it easy to transport the kit from one location to another.

[0257] In one exemplarily embodiment, the kit comprises the apparatus according to the sixth aspect, and a storage container and / or carrying case.

[0258] Some common apparatuses include spray bottles, trigger sprayers, backpack sprayers, electrostatic sprayers, and disinfecting wipes. The specific items that are included in a kit for applying disinfectant will vary depending on the type of kit and the intended use. For example, a kit that is designed for use in a healthcare setting may include different items than a kit that is designed for use in a home.

[0259] When choosing a kit for applying disinfectant, it is important to consider the following factors: The type of disinfectant being used.

[0260] The surface being disinfected.

[0261] The desired outcome.

[0262] The specific needs of the user or environment.

[0263] It is also important to follow the manufacturer's instructions for using the kit safely and effectively.

[0264] In an eight aspect, the present invention relates to a household cleaner, disinfectant, sanitizer, or wet wipe comprising the disinfectant formulation according to the first aspect.

[0265] In a ninth aspect, the present invention relates to the use of a silk polypeptide to impart a prolonged and residual biocidal property to a biocidal compound.

[0266] Various modifications and variations of the invention will be apparent to those skilled in the art without departing from the scope of 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 which are obvious to those skilled in the art in the relevant fields are intended to be covered by the present invention.

[0267] BRIEF DESCRIPTION OF THE FIGURES

[0268] The following figures are merely illustrative of the present invention and should not be construed to limit the scope of the invention as indicated by the appended claims in any way.

[0269] Figure 1: Shows the composition of the disinfectant formulations tested.

[0270] Figure 2: Shows the BSI PAS2424 test results.

[0271] EXAMPLES

[0272] The examples given below are for illustrative purposes only and do not limit the invention described above in any way. Specifically, the following examples illustrate liquid formulations made in accordance with aspects of the present invention. The testing results on these formulations demonstrate the desired residual disinfecting performance once being applied onto surfaces and dried. Cleaning performance is also tested on those formulations that not only provide residual disinfecting benefit but also cleaning features.

[0273] The chosen testing Protocols is based on the BSI PAS2424 - Quantitative surface test for the evaluation of residual antimicrobial (bactericidal and / or yeasticidal) efficacy of liquid chemical disinfectants on hard non-porous surfaces - Test method. As the norm states "At present there is no European Standard test methodology for assessing the residual antimicrobial activity of a chemical disinfectant / antimicrobial product, therefore researchers and companies have designed test methods in an attempt to demonstrate residual antimicrobial efficacy and support these claims. However, these methods largely involve applying a product to a surface and leaving it for a defined period of time before challenging with micro-organisms.". "The test method in PAS 2424 has therefore been designed to reflect within a laboratory test method the actual conditions in which a product is designed to be used. It takes into consideration abrasion and recontamination by including abrasion cycles and re-inoculations over a 24-h period and remains as close as possible to the practical conditions that are outlined in the current European Standards (e.g. test surface, contact times, micro-organisms, organic load, etc)”. A pass result refers to at least 99.9% reduction (log 3 reduction) in bacteria and yeasts at the end of the abrasion regimes after 24 hours.

[0274] Different disinfectant formulations were tested, 3 with very typical biocidal activity based on quaternary ammonium compounds, with silk polypeptides inside, and compared with the same without silk polypeptides, and compared also with a formula without Quats at all and one without silk polypeptides and without Quats. The different disinfectant formulations are shown in Figure 1. The results are shown in Figure 2. It can be shown that all formulation with filming biopolymer (A, B, C) showed a positive pass result compared to the control without filming biopolymer (Al, Bl, Cl). The formulations without active biocidal (D an DI) served as negative control.

Claims

CLAIMS1. A disinfectant formulation comprising: a biocidal compound, and a silk polypeptide.

2. The disinfectant formulation of claim 1, wherein the formulation functions as biocide and imparts a prolonged and residual biocidal property.

3. The disinfectant formulation of claims 1 or 2, wherein the biocidal compound and the silk polypeptide are (evenly) distributed in the formulation.

4. The disinfectant formulation of any one of claims 1 to 3, wherein the formulation is free of any cross-linker or binding agent.

5. The disinfectant formulation of any one of claims 1 to 4, wherein the biocidal compound is selected from the group consisting of a quaternary ammonium compound, citric acid, sulfamic acid, glycolic acid, lactic acid, lauric acid, capric acid, silane quaternary salts, triclosan, zinc pyrithione, metal salt, metal oxide, phenol, botanical, halogen, peroxide, heterocyclic antimicrobial, an aldehyde, and an alcohol, or is a combination thereof.

6. The disinfectant formulation of any one of claims 1 to 5, wherein the silk polypeptide comprises or consists of (at least two identical) repetitive units.

7. The disinfectant formulation of any one of claims 1 to 6, wherein the silk polypeptide does not comprise / is free of non-repetitive units.

8. The disinfectant formulation of claims 6 or 7, wherein the repetitive units are independently selected from the group consisting of module C having an amino acid sequence according to SEQ ID NO: 1 or variants thereof, module CCyshaving an amino acid sequence according to SEQ ID NO: 2 or variants thereof, and module CLyshaving an amino acid sequence according to SEQ ID NO: 3 or variants thereof.

9. The disinfectant formulation of any one of claims 1 to 8, wherein the silk polypeptide comprises or consists of (C)m, (C)mCCys, (C)mCLys, CCys(C)m, CLys(C)m, (CCys)m, or (CLys)m, wherein m is an integer of between 2 to 96.

10. The disinfectant formulation of claim 9, wherein the silk polypeptide comprises or consists(C)32CCys, (C)48CCys, (C)2CLys, (C)4CLys, (C)6CLys, (C)8CLys, (C)i6CLys, (C)32CLys, (C)48CLys, CCys(C)2, CCys(C)4, CCys(C)6, CCys(C)8, CCys(C)i6, CCys(C)32, CCys(C)48, CLys(C)2, CLys(C)4, CLys(C)6, CLys(C)8, CLys(C)i6, CLys(C)32, CLys(C)48, cCys2, cCys4, CCys6, cCys8, CCysi6, CCys32, CCys48, CLys2, CLys4, CLys6, CLys8, CLysi6, CLys32, or CLys48.

11. The disinfectant formulation of any one of claims 1 to 10, wherein the formulation is in form of a liquid or an (a pressurized) aerosol.

12. The disinfectant formulation of any claim 11, wherein the formulation is in form of a liquid and wherein the biocidal compound is present in the liquid in a range of between 0.05% and 10% based on the weight of the disinfectant formulation, and / or the silk polypeptide is present in the liquid in a range of between 0.01% and 10% based on the weight of the disinfectant formulation.

13. The disinfectant formulation of any one of claims 1 to 12, wherein the formulation further comprises a carrier.

14. The disinfectant formulation of claim 13, wherein the carrier comprises one or more solvents.

15. The disinfectant formulation of claim 14, wherein the one or more solvents are selected from the group consisting of an aqueous solution, preferably water or a buffered aqueous solution, a low molecular weight alcohol, an alkylene glycol ether, a terpene, and a terpene derivative.

16. The disinfectant formulation of claim 15, wherein(i) the low molecular weight alcohol is selected from the group consisting of ethanol, isopropyl alcohol, butanol, and pentanol, or is a combination thereof,(ii) the alkylene glycol ether is selected from the group consisting of ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene clycol monohexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, propylene glycol methyl ether, propylene glycol methyl ether acetate, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, dipropylene glycol methyl ether, dipropylene glycol methyl ether acetate, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, and tripropylene glycol methyl ether, or is a combination thereof, and / or(iii) the terpene is selected form the group consisting of a terpene alcohol, terpene ester, terpene ether, and terpene aldehyde, or is a combination thereof.

17. The disinfectant formulation of any one of claims 1 to 16, wherein the formulation further comprises a surfactant or a wetting agent.

18. The disinfectant formulation according to claim 17, wherein the surfactant is present in a range of between 0.01% and 10%.

19. The disinfectant formulation of claims 17 or 18, wherein the surfactant is nonionic, anionic, or amphoteric in nature.

20. The disinfectant formulation of any one of claims 1 to 19, wherein the formulation further comprises a pH adjusting agent.

21. The disinfectant formulation of claim 20, wherein the pH adjusting agent is selected from the group consisting of triethanolamine, diethanolamine, monoethanolamine, sodium hydroxide, sodium carbonate, potassium hydroxide, potassium carbonate, calcium carbonate, citric acid, acetic acid, hydrochloric acid, sulfamic acid, and sulfuric acid, or is a combination thereof.

22. The disinfectant formulation of any one of claims 1 to 21, wherein the formulation further comprises one or more additional components selected from the group consisting of a corrosion inhibitor, chelant, compatibilizer, coupling agent, corrosion inhibitor, rheologymodifier, fragrance, colorant, preservative, an UV stabilizer, an optical brightener, and an active ingredient indicator.

23. The disinfectant formulation of claim 22, wherein the formulation comprises or consists of a biocidal compound, a silk polypeptide, water (solvent), mono propylene glycol (additional solvent), a surfactant, preferably non-ionic C12-C14-7 EO, a chelant, preferably GLDA, an acidic buffering system (pH adjusting agent), preferably Na Citrate, a fragrance, and a colorant.

24. The disinfectant formulation of any one of claims 11 to 23, wherein the formulation is in form of a pressurized aerosol and further comprises a propellant.

25. The disinfectant formulation of claim 24, wherein the propellant is selected from the group consisting of Cl to CIO hydrocarbons or halogenated hydrocarbons, compressed air, nitrogen, and carbon dioxide.

26. A method of disinfecting a surface comprising the steps of(i) providing a disinfectant formulation of any one of claims 1 to 25, and(i) applying the disinfectant formulation to / onto a surface, thereby disinfecting the surface.

27. The method of claim 26, wherein the formulation functions as biocide and imparts a prolonged and residual biocidal property.

28. The method of claims 26 or 27, wherein the application of the disinfectant formulation takes place via spraying, fogging, rolling, brushing, mopping, wiping, or via a combination thereof.

29. The method of any one of claims 26 to 28, wherein application of the disinfectant formulation results in a film on the surface / coats the surface.

30. The method of claims any one of claims 26 to 29, wherein the method further comprises the step of(iii) drying the surface.

31. The method of any one of claims 26 to 30, wherein the surface is a solid surface.

32. The method of any one of claims 26 to 31, wherein the surface is a non-porous surface.

33. The method of any one of claims 26 to 32, wherein the surface is a surface with contact to food / associated with food preparation, a household surface, a surface in a health care environment, a surface associated with hospital environments, a surface associated in a medical laboratory, a surface in a medical treatment environment, a surface in the institutional and hospitality environment, a lavatory fixture, a lavatory appliance, a wall, and a flooring surface.

34. The method of any one of claims 26 to 33, wherein the surface is selected from the group consisting of a synthetic inert surface, an inorganic inert surface, and a naturally occurring surface.

35. The method of claim 34, wherein the(i) synthetic inert surface is selected from the group consisting of polyester, polystyrene, polyamide (PA), polyaramid, polytetrafluorethylene (PTFE), polyethylene (PE), polypropylene (PP), polyurethane (PU), silicone, a mixture of polyurethane and polyethylenglycol (elastane), ultra-high molecular weight polyethylene (UHMWPE), high-performance polyethylene (HPPE), and melamine formaldehyde,(ii) inorganic inert surface is selected from the group consisting of, glass, carbon, ceramic, metal, marble, granitic, quartz, concrete, and semiconductor, or(iii) the naturally occurring surface is wood, cotton, or wool.

36. The method of any one of claim 26 to 35, wherein the surface is the surface / part of an article.

37. The method of claim 36, wherein the article is a device.

38. The method of claim 37, wherein the device is selected from the group consisting of a medical device, a wet room fitting, a heating device, a ventilation device, an air condition device, a household appliance, an electronic device, and a device used in food industry.

39. An article coated on its surface with or comprising on its surface the disinfectant formulation of any one of claims 1 to 25.

40. The article of claim 39, wherein the article is a device.

41. The article of claim 40, wherein the device is selected from the group consisting of a medical device, a wet room fitting, a heating device, a ventilation device, an air condition device, a household appliance, an electronic device, and a device used in food industry.

42. Use of the disinfectant formulation of any one of claims 1 to 25 to disinfect a surface.

43. Use of the disinfectant formulation of any one of claims 1 to 25 as disinfectant for home care, household, hospital care, laboratory care, medical care, or food service industry.

44. An apparatus comprising the disinfectant formulation of any one of claims 1 to 25.

45. The apparatus of claim 44, wherein the apparatus is a spraying apparatus.

46. A kit comprising the disinfectant formulation of any one of claims 1 to 25, or the apparatus of claims 44 or 45.

47. A household cleaner, disinfectant, sanitizer, or wet wipe comprising the disinfectant formulation of any one of claims 1 to 25.

48. Use of a silk polypeptide to impart a prolonged and residual biocidal property to a biocidal compound.

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