Use of compositions containing 2-ethylhexyl laurate for treating ectoparasites

Abstract

The present invention relates to the use of 2-ethylhexyl laurate for killing ectoparasites and / or their eggs.

Description

[0001] Use of compositions containing 2-ethylhexyl laurate for the treatment of ectoparasites

[0002] The present invention relates to compositions for killing ectoparasites and / or their eggs on a living organism and methods for doing so.

[0003] BACKGROUND OF THE INVENTION

[0004] Ectoparasites are organisms that live on the skin or skin growths of another organism (the host) for varying periods of time and can harm the host. Various ectoparasites cause significant infestations in humans and many types of domestic animals, including farm animals, laboratory animals, poultry, fish, and bees. Many of these ectoparasites (e.g., most lice) are host-specific, while others (e.g., many ticks) parasitize a broader range of hosts.

[0005] Many ectoparasites are known to be vectors of pathogens, which the parasites typically transmit to their host during feeding or, in some cases, through feces. Examples of ectoparasites include lice, ticks, mites, and fleas.

[0006] Lice are external parasites of warm-blooded hosts. Humans harbor three different species of lice: head lice (Pediculus humanus capitis), body lice (Pediculus humanus humanus or Pediculus humanus corporis), and pubic lice (Phthirus pubis). All three species are blood-sucking, human-pathogenic parasites that exclusively parasitize humans, using them as a habitat and food source. Head lice infestation (Pediculosis capitis) is a persistent global problem. In the USA alone, it is estimated that there are between 6 and 12 million head lice infestations annually. Despite regional studies, reliable data on the global prevalence is lacking; some sources estimate that around 100 million people are affected each year. The problem is particularly common among children aged 3 to 13 and their families. It is estimated that approximately 1 to 3% of children in Germany are currently affected by head lice.In childhood, head lice infestation is therefore the most common parasitic disease and, after colds, the second most common infectious disease.

[0007] Head lice infestation typically manifests as itching of the scalp. Since lice feed exclusively on human blood, they use their piercing mouthparts to suck blood from their host's scalp several times a day. At the bite sites, an immune response causes intensely itchy papules and wheals to develop. The scratching induced by the itching can lead to scalp lesions—potential entry points for bacteria, with the risk of bacterial superinfection and resulting swollen lymph nodes in the neck and throat area—or other symptoms. In addition to the medical problems, head lice infestation also causes psychosocial problems, not least due to the often unjustified stigmatization of those affected and their families.Furthermore, head lice infestation (Pediculosis capitis) is also significant from a health economics and macroeconomic perspective, as it places a burden on the healthcare system and generates considerable costs, such as those for treatments, doctor's visits, involvement of public health departments, lost school days, necessary childcare due to the exclusion of children from community facilities, and absenteeism from work. Body lice are also a nuisance to humans and pose the additional risk of transmitting dangerous infectious diseases, such as typhus or louse-borne relapsing fever.

[0008] The life cycle of the head louse goes through three developmental stages: egg, nymph, and adult louse. The louse's hard chitinous exoskeleton serves as protection against external influences. Lice eggs similarly have a protective chitinous shell surrounding the louse embryos. The eggs are firmly attached to the hair shaft near the scalp to protect them from temperature fluctuations and drying out. The female louse lives for up to 30 days and can lay a maximum of 300 eggs during this time. From the attachment of an egg to the hair to the mature, reproductive louse, a minimum of 17 to a maximum of 21 days pass. The nymphs (also called larvae) already look like small lice and usually hatch from the eggs 7-8 days after they are laid. Through three stages, the nymphs then develop into adult, sexually mature lice within 9-12 days.After the nymphs hatch, the empty and harmless chitinous shells (nits) remain visibly attached to the hair for a long time (sometimes for months). Colloquially, the eggs of the louse are also often referred to as nits.

[0009] The goal of any treatment is the rapid and complete elimination of all head lice and their developmental stages. Successful treatment of a lice infestation therefore includes killing all developmental stages: mature lice, nymphs, and eggs. It must be considered that eggs can prove more resistant to treatment than lice or nymphs. An effective lice treatment (pediculocide) is accordingly characterized by killing both mature lice and nymphs (pediculocidal effect) and interrupting egg development or killing the lice embryos (ovicidal effect) – ideally after the first application.

[0010] To ensure successful treatment, the Robert Koch Institute recommends repeating the treatment after 9 (+ / - 1) days, even with highly effective lice treatments. This is because nymphs can still hatch from unkilled eggs until the 7th or 8th day after the initial treatment, and young females could be laying new eggs from the 11th day onwards.

[0011] Treatment options for head lice infestation can be roughly divided into five groups as follows: topically applied, neurotoxic agents based on neurotoxins (classic insecticides); topically applied, physically acting agents; topically applied, homeopathic, herbal formulations and other remedies; oral, systemically acting agents; mechanical agents such as combs.

[0012] Various products with different compositions are available for treating lice infestations, generally employing a topical approach. Most of these treatments involve the use of physically acting or plant-based formulations. The use of neurotoxic agents based on traditional insecticides has declined significantly due to concerns about their toxicological safety and efficacy. Furthermore, as lice become increasingly resistant to the insecticides used, these formulations may lose their effectiveness.

[0013] US 6,303,581 teaches the use of various surfactants, including non-volatile lipids, non-volatile fatty alcohols and non-volatile fatty esters or mixtures thereof, which are water-soluble or contain water and have been shown to be pediculostatic.

[0014] EP 0968706B1 discloses shampoo compositions containing spynosines, surfactants and amides.

[0015] WO2001 019190 discloses compositions containing 85 to 99.9% cyclosiloxanes and other special siloxanes as pediculicides.

[0016] WO2001 040446 discloses the ectoparasiticidal activity of a composition comprising a carrier (e.g. isopropyl myristate and / or octyl palmitate) and an active ingredient such as spynosin or ivermectin.

[0017] WO03092583 discloses compositions for killing ectoparasites in a patient, containing a fatty acid ester, e.g., isopropyl myristate, which is effective in killing ectoparasites. Also described are compositions containing a fatty acid ester and a siloxane (e.g., decacyclomethicone).

[0018] EP 1993363B1 discloses a composition for killing ectoparasites and / or their eggs, comprising 30-49 wt% of a low-viscosity linear polysiloxane with a viscosity of less than 10 cSt, 35-65 wt% of a high-viscosity linear polysiloxane with a viscosity of more than 90 cSt and at least one spreading agent.

[0019] These developments and inventions have led to the availability of various treatments for head lice infestation, most of which are physically based. The use of neurotoxic substances as active ingredients in lice treatments has declined due to pharmacological and toxicological concerns, as well as the increasing global development of resistant head lice strains.

[0020] Nevertheless, there remains a need for well-tolerated, toxicologically safe agents for treating head lice, especially preparations that require only one application and also kill the lice eggs. The use of biodegradable ingredients or those made from renewable resources is therefore becoming increasingly important. It is crucial to remember that these preparations are washed off and rinsed away after application, and thus a large portion ends up in wastewater.

[0021] SUMMARY OF THE INVENTION

[0022] The invention relates to the use of 2-ethylhexyl laurate for killing ectoparasites and / or their eggs.

[0023] The invention further relates to a medical device or pharmaceutical containing 2-ethylhexyl laurate and at least one other substance that kills ectoparasites and / or their eggs, preferably sorbitan sesquicaprylate or methyl glucose diolate. DETAILED DESCRIPTION OF THE INVENTION

[0024] The invention relates to the use of 2-ethylhexyl laurate for killing ectoparasites and / or their eggs.

[0025] Within the scope of the present invention, it has surprisingly been shown that 2-ethylhexyl laurate kills ectoparasites and / or their eggs (see examples). Therefore, 2-ethylhexyl laurate (hereinafter also referred to as "EHL") is particularly suitable for the treatment of head lice. In the context of the present invention, the term ectoparasites includes not only the adult (mature) but also the immature developmental stages of the respective ectoparasite, such as the nymphs of head lice.

[0026] The examples demonstrated that the compositions according to the invention rapidly penetrate the tracheal system within the louse's body via the insect's respiratory openings (tracheal openings or spiracles) and displace the air from the system. After application of the compositions according to the invention, the insects very quickly cease to show vital signs and suffocate. While not bound by theory, it is hypothesized that 2-ethylhexyl laurate, due to its polarity and other physicochemical properties, possesses a high affinity for chitin and could therefore lead to rapid distribution of the preparation within the tracheal system. It is also assumed that the compositions according to the invention have an ovicidal effect and thus also kill the embryos in the eggs of the insects or lice.Insect eggs also have spiracles through which they connect to the outside air and through which the compositions according to the invention can penetrate. In this way, the compositions can also displace the air inside the eggs and counteract further gas exchange or the supply of oxygen, which could lead to the killing of the eggs. In lice, these spiracles, the so-called aeropyles, are located in the operculum of the egg. The term ectoparasites, as used in the present application, preferably includes lice, ticks, mites, and fleas. The invention particularly preferably relates to the killing of lice, preferably head lice, and / or their eggs.

[0027] In the course of the invention, it has surprisingly been found that 2-ethylhexyl laurate is also suitable for killing other insects (see Example 7). Therefore, the invention also relates to the use of 2-ethylhexyl laurate for killing insects in general. All embodiments mentioned below also relate to this use according to the invention.

[0028] EHL is a substance that is commercially available under the trade name Rofetan® 148, among others. Commercially available EHL often contains esters of other fatty acids (caproic, caprylic, capric, and myristic acid) and esters of other alcohols isomeric to 2-ethylhexanol. These can be used in conjunction with the EHL, provided they do not exceed 30% of the total amount.

[0029] In principle, EHL can be used in any quantity suitable for treating ectoparasites. According to a particularly preferred embodiment, the 2-ethylhexyl laurate is used in a preparation containing 10–95% 2-ethylhexyl laurate, preferably 30–95%, 50–95%, or 70–90%, and particularly preferably 78–85% 2-ethylhexyl laurate.

[0030] In the context of this application, all percentages refer to weight percentages unless otherwise stated.

[0031] In a preferred embodiment of the invention, at least one additional substance is used that kills ectoparasites and / or their eggs.

[0032] According to a further preferred embodiment, the substance is selected from the group of surfactants. Surfactants are substances that reduce the surface tension of a liquid or the interfacial tension between two phases and enable or promote the formation of dispersions, or act as solubilizers.

[0033] Within the scope of this invention, surfactants from the group of fatty acid-esterified methyl glycosides or fatty acid-esterified polyols, partial glycerides and mixtures thereof are preferably used.

[0034] Preferably, the surfactant(s) is used in a preparation containing 5-80%, preferably 5-20%, surfactants.

[0035] Methyl glucose diolate, sorbitan sesquicaprylate, sorbitan monooleate and / or glyceryl caprylate are preferably used as surfactants.

[0036] Methyl glucose dioleate, as defined in this invention, is a diesterified methyl glycoside characterized in that its fatty acid component is oleic acid. Methyl glucose dioleate is a commercially available substance marketed by Lubrizol under the trade name Glucate™ DO emulsifier. According to a particularly preferred embodiment, methyl glucose dioleate is used in a preparation containing 5–50% methyl glucose dioleate, particularly preferably 5–20%.

[0037] Sorbitan sesquicaprylate, as defined in this invention, is a mono- and di-esterified sorbitan characterized in that the fatty acid component is caprylic acid. Sorbitan sesquicaprylate is a commercially available substance, marketed, for example, by Evonik under the trade name ANTIL® Soft SC MB. Sorbitan sesquicaprylate is preferably used in a preparation containing 5–50% sorbitan sesquicaprylate, particularly preferably 5–20%. Sorbitan monooleate, as defined in this invention, is a sorbitan fatty acid ester with a fatty acid, primarily oleic acid, linoleic acid, and palmitic acid, characterized in that the fatty acid component contains at least 50% oleic acid. Particularly preferred is the use of sorbitan monooleate according to the European Pharmacopoeia, which contains in its fatty acid content not less than 65% and not more than 88% oleic acid and not more than 18% linoleic acid and 16% palmitic acid.Sorbitan monooleate is preferably used in a preparation containing 5-50% sorbitan monooleate, particularly preferably 5-20% sorbitan monooleate.

[0038] Glyceryl caprylate, as defined in this invention, is a mixture of mono-, di-, and triacylglycerols of caproic, caprylic, capric, and lauric acid, characterized in that the mixture contains at least 45% monoacylglycerols and at least 50% caprylic acid in the fatty acid fraction, with mixtures containing at least 80% monoacylglycerols and at least 90% caprylic acid in the fatty acid fraction being preferred. Glyceryl caprylate is preferably used in a preparation containing 5–25% glyceryl caprylate, particularly preferably 5–15% glyceryl caprylate.

[0039] According to a further preferred embodiment of the invention, the additional substance that kills ectoparasites and / or their eggs is selected from the group of branched-chain carboxylic acid esters. Isoamyl laurate is preferably used, preferably in a preparation with a concentration of 1–20%, more preferably in a concentration of 1–8%.

[0040] In one embodiment, the preparation according to the invention contains 2-ethylhexyl laurate, methyl glucose diolate, and isoamyl laurate. Preferably, more than 50% 2-ethylhexyl laurate, particularly preferably more than 60% or 70%, 5–20% methyl glucose diolate, and 1–8% isoamyl laurate are used.

[0041] According to another preferred embodiment, further cosmetically or pharmaceutically acceptable substances are used. These include oils, emollients, thinners, preservatives, stabilizers, fragrances, and substances that improve hair combability and facilitate the removal of nits and lice from the hair.

[0042] Preferably, one or more substances are used that improve the combability of hair or the removal of ectoparasites and / or their eggs. Such substances are known in the prior art. These can be medium-chain hydrocarbons, medium- and long-chain alcohols, and aliphatic esters. Dicaprylyl carbonate or 2,5-dimethyl isosorbide are preferably used, preferably in a preparation with a concentration of 0.1–30%, more preferably in a concentration of 5–20%.

[0043] Within the scope of the use according to the invention, it is possible that the individual substances are used in different preparations and that a mixture of the preparations takes place during the use according to the invention.

[0044] However, within the scope of the present invention, it is preferred that all substances used are present in one preparation.

[0045] In one embodiment, the preparation according to the invention contains 75 - 85% 2-ethylhexyl laurate, 5 - 15% methyl glucose dioleate and 4 - 6% isoamyl laurate.

[0046] According to a further preferred embodiment, the preparation used contains at least one substance that reduces the viscosity and / or improves the sprayability. Such substances are known in the prior art. Preferably, the at least one substance is selected from the group consisting of esters of short-chain mono- and dicarboxylic acids with short-chain primary alcohols, preferably diethyl succinate, and water.

[0047] Within the scope of the invention, it was surprisingly found that preparations according to the invention containing less than 1% water are particularly effective in killing lice eggs. Therefore, in a preferred embodiment, the preparation according to the invention contains less than 1% water, preferably less than 0.5% or 0.1%. The preparations according to the invention can also contain no water at all.

[0048] According to a further preferred embodiment of the invention, the preparation contains triglycerides used for viscosity adjustment. Soybean oil, sesame oil, argan oil, or partially hydrogenated rapeseed oil are preferred. The oils are preferably used in a preparation containing 5–30% of one oil, particularly preferably 10–20%.

[0049] Within the scope of the invention, viscosity can be measured using any suitable method. Such methods are known to those skilled in the art. For example, viscosity measurement can be carried out on a cone-plate rheometer with a C60 / 1 0 TiL cone at 20 °C and a shear rate of 1500 s _1 take place.

[0050] According to a preferred embodiment, this preparation has a viscosity of no more than 60 mPas, preferably measured on a cone-plate rheometer with a C60 / 1 0 Cone at 20 °C and a shear rate of 1500 s' 1 on.

[0051] The preparations according to the invention have a density of approximately 0.8 - 1.0 g / cm³. 3 Since the dynamic viscosities in mPas can be converted into the kinematic viscosities in cSt via the density, the numerical values ​​of the dynamic viscosities of the preparations according to the invention in mPas correspond approximately to those of the kinematic viscosities of the preparations according to the invention in cSt.

[0052] According to a preferred embodiment, the preparations contain 0.01–2.0% fragrances. Such fragrances are known to those skilled in the art. Fresh citrus-like fragrances such as lemon peel oil, orange peel oil, or boabo oil are preferred.

[0053] In a preferred embodiment, the preparation according to the invention contains or consists of 2-ethylhexyl laurate; triglycerides selected from soybean oil, sesame oil, argan oil, and partially hydrogenated rapeseed oil; isoamyl laurate; refined jojoba wax and boabo oil.

[0054] In a preferred embodiment, the preparation according to the invention consists of 84% 2-ethylhexyl laurate, 10% argan oil, 4.95% isoamyl laurate, 1% refined jojoba wax and 0.05% boabo oil.

[0055] In a preferred embodiment, the preparation according to the invention contains or consists of 2-ethylhexyl laurate, methyl glucose dioleate, 2,5-dimethyl isosorbide, isoamyl laurate, refined jojoba wax and boabo oil.

[0056] In a preferred embodiment, the preparation according to the invention consists of 79% 2-ethylhexyl laurate, 10% methyl glucose dioleate, 5.0% 2,5-dimethyl isosorbide, 4.95% isoamyl laurate, 1% refined jojoba wax and 0.05% boabo oil.

[0057] In a preferred embodiment, the preparation according to the invention contains or consists of 2-ethylhexyl laurate, glyceryl caprylate, isoamyl laurate, refined jojoba wax and boabo oil.

[0058] In a preferred embodiment, the preparation according to the invention consists of 84% 2-ethylhexyl laurate, 10% glyceryl caprylate, 4.95% isoamyl laurate, 1% refined jojoba wax and 0.05% boabo oil.

[0059] In a preferred embodiment, the preparation according to the invention contains or consists of 2-ethylhexyl laurate, methyl glucose diolate, isoamyl laurate, refined jojoba wax and boabo oil.

[0060] In a preferred embodiment, the preparation according to the invention consists of 84% 2-ethylhexyl laurate, 10% methyl glucose diolate, 4.95% isoamyl laurate, 1% refined jojoba wax, and 0.05% boabo oil. In a preferred embodiment, the preparation according to the invention contains or consists of 2-ethylhexyl laurate, sorbitan monooleate, isoamyl laurate, refined jojoba wax, and boabo oil.

[0061] In a preferred embodiment, the preparation according to the invention consists of 79% 2-ethylhexyl laurate, 15% sorbitan monooleate, 4.95% isoamyl laurate, 1% refined jojoba wax and 0.05% boabo oil.

[0062] In a preferred embodiment, the preparation according to the invention contains or consists of 2-ethylhexyl laurate, sorbitan sesquicaprylate, isoamyl laurate, refined jojoba wax and boabo oil.

[0063] In a preferred embodiment, the preparation according to the invention consists of 74% 2-ethylhexyl laurate, 20% sorbitan sesquicaprylate, 4.95% isoamyl laurate, 1% refined jojoba wax and 0.05% boabo oil.

[0064] In a further preferred embodiment, the preparation according to the invention contains or consists of 2-ethylhexyl laurate, sorbitan monooleate, glyceryl caprylate, water, isoamyl laurate, refined jojoba wax and boabo oil.

[0065] In a further preferred embodiment, the preparation according to the invention consists of 31% 2-ethylhexyl laurate, 7% sorbitan monooleate, 42% glyceryl caprylate, 14% water, 4.95% isoamyl laurate, 1% refined jojoba wax and 0.05% boabo oil.

[0066] The use according to the invention can be either therapeutic or cosmetic.

[0067] Furthermore, the invention also relates to a preparation containing 2-ethylhexyl laurate and at least one further substance that kills ectoparasites and / or their eggs, preferably sorbitan sesquicaprylate or methyl glucose diolate. The invention further relates to a preparation with a viscosity of not more than 100 cSt, containing 2-ethylhexyl laurate and 2,5-dimethyl isosorbide. The invention further relates to a preparation with a viscosity of not more than 100 mPas, containing 2-ethylhexyl laurate and 2,5-dimethyl isosorbide.

[0068] Furthermore, the invention also relates to a preparation with a viscosity of not more than 100 cSt, containing 2-ethylhexyl laurate, methyl glucose diolate, and 2,5-dimethyl isosorbide. Furthermore, the invention also relates to a preparation with a viscosity of not more than 100 mPas, containing 2-ethylhexyl laurate, methyl glucose diolate, and 2,5-dimethyl isosorbide.

[0069] The invention further relates to a medical device, cosmetic or pharmaceutical containing 2-ethylhexyl laurate.

[0070] Preferably, the medical device, cosmetic or pharmaceutical according to the invention contains at least one further substance that kills ectoparasites and / or their eggs, preferably sorbitan sesquicaprylate or methyl glucose dioleate.

[0071] The same embodiments apply to the medical device, cosmetic or pharmaceutical or preparations according to the invention as to the use according to the invention described above.

[0072] The substances, preparations, medical devices, cosmetics, or pharmaceuticals according to the invention (singular or plural) are preferably used topically. In the case of head lice, they are preferably applied to the head, although other body regions are also included according to the invention.

[0073] The invention is further explained by the following examples, which are not intended to limit the invention. In particular, the examples illustrate the preparation of solutions according to the invention and their effect on crickets (Acheta domesticus) and body lice. These are standard animal models for ectoparasites, especially head lice. Examples

[0074] Viscosity measurements in all examples were performed on a cone-plate rheometer with a C60 / 1 0 Cone at 20 °C and a shear rate of 1500 s- 1 .

[0075] Example 1: Dilution of 2-ethylhexyl laurate with diethyl succinate

[0076] Diethyl succinate has no effect on the insects and was therefore chosen as an inert diluent.

[0077] The quantities listed in the following table were weighed into a 20 ml glass and homogenized by stirring with a magnetic stirrer at room temperature:

[0078] Comparative example 1: Dilution of isopropyl myristate with diethyl succinate

[0079] The quantities listed in the following table were weighed into a 20 ml glass and homogenized by stirring with a magnetic stirrer at room temperature: Example 2: Addition of other effective ingredients

[0080] Glyceryl caprylate is heated in a water bath (55–60 °C) to liquefy it before use. The quantities listed in the following table were weighed into a 20 ml glass and homogenized by stirring with a magnetic stirrer at room temperature:

[0081] Examples 3-6 describe the composition and manufacture of further preparations according to the invention.

[0082] Example 3: Addition of further components (fragrances, substances that reduce viscosity)

[0083] Example 3a: A stock solution is prepared from 95.24 g refined jojoba wax and 4.77 g boabo oil. 1.00 g argan oil, 8.40 g 2-ethylhexyl laurate, 0.50 g isoamyl laurate, and 0.10 g of the refined jojoba wax / boabo oil solution are added to a glass vial at room temperature and stirred for 60 minutes.

[0084] Example 3b: A stock solution is prepared from 95.24 g refined jojoba wax and 4.77 g boabo oil. 1.00 g partially hydrolyzed rapeseed oil, 8.39 g 2-ethylhexyl laurate, 0.50 g isoamyl laurate, and 0.11 g of the refined jojoba wax / boabo oil solution are added to a glass vial at room temperature and stirred for 60 minutes.

[0085] Example 3c: A stock solution is prepared from 95.24 g refined jojoba wax and 4.77 g boabo oil. 1.50 g soybean oil, 7.90 g 2-ethylhexyl laurate, 0.50 g isoamyl laurate, and 0.11 g of the refined jojoba wax / boabo oil solution are added to a glass vial at room temperature and stirred for 60 minutes.

[0086] Example 3d: A stock solution is prepared from 95.24 g refined jojoba wax and 4.77 g boabo oil. 2.00 g sesame oil, 7.40 g 2-ethylhexyl laurate, 0.50 g isoamyl laurate, and 0.11 g of the refined jojoba wax / boabo oil solution are added to a glass vial at room temperature and stirred for 60 minutes. Example 4: Addition of further components (surface-active agents, fragrances, substances that reduce viscosity)

[0087] Example 4a: 588.0 g of 2-ethylhexyl laurate are placed in an iodine flask, and while stirring at room temperature, 69.99 g of methyl glucose dioleate, 34.65 g of isoamyl laurate, 7.00 g of refined jojoba wax, and 0.35 g of boabo oil are added. Finally, the solution is stirred for a further 15 minutes.

[0088] Example 4b: Glyceryl caprylate is heated in a water bath (55–60 °C) to liquefy it before use. 179.84 g of 2-ethylhexyl laurate are placed in a 500 ml iodine flask, and while stirring at room temperature, 60.01 g of glyceryl caprylate, 15.01 g of isoamyl laurate, 42.01 g of diethylene glycol monoethyl ether, 3.00 g of refined jojoba wax, and 0.153 g of boabo oil are added. Finally, the solution is stirred for a further 15 minutes.

[0089] Example 4c: Glyceryl caprylate is heated in a water bath (55–60 °C) to liquefy it before use. 179.88 g of 2-ethylhexyl laurate are placed in a 500 ml iodine flask, and while stirring at room temperature, 30.00 g of glyceryl caprylate, 30.01 g of sorbitan monooleate, 42.00 g of diethylene glycol monoethyl ether, 15.00 g of isoamyl laurate, 3.00 g of refined jojoba wax, and 0.147 g of boabo oil are added. Finally, the solution is stirred for a further 15 minutes.

[0090] Example 4d: Glyceryl caprylate is heated in a water bath (55–60 °C) to liquefy it before use. A stock solution is prepared from 23.82 g of refined jojoba wax and 1.20 g of boabo oil. 63.95 g of 2-ethylhexyl laurate are placed in a 200 ml iodine flask, and while stirring at room temperature, 10.00 g of glyceryl caprylate, 20.04 g of methyl glucose dioleate, 5.01 g of isoamyl laurate, and 1.04 g of the refined jojoba wax / boabo oil solution are added. Finally, the solution is stirred for a further 15 minutes.

[0091] Example 4e: A stock solution is prepared from 95.24 g of refined jojoba wax and 4.77 g of boabo oil. 2.00 g of sorbitan sesquicaprylate, 7.41 g of 2-ethylhexyl laurate, 0.50 g of isoamyl laurate, and 0.11 g of the refined jojoba wax / boabo oil solution are added to a glass vial at room temperature and stirred for 60 minutes.

[0092] Example 5: Addition of further ingredients (surface-active substances, fragrances, substances that improve combability and / or reduce viscosity)

[0093] Example 5a: A stock solution is prepared from 28.58 g of refined jojoba wax and

[0094] 1.43 g of Boabo oil were prepared. 237.00 g of 2-ethylhexyl laurate were placed in a 500 ml iodine flask, and while stirring at room temperature, 30.00 g of methyl glucose diolate, 15.01 g of 2,5-dimethyl isosorbide, 14.85 g of isoamyl laurate, and 3.15 g of the refined jojoba wax / Boabo oil solution were added. Finally, the solution was stirred for a further 15 minutes.

[0095] Example 5b: A stock solution is prepared from 28.57 g of refined jojoba wax and 1.43 g of boabo oil. 206.86 g of 2-ethylhexyl laurate are placed in a 500 ml iodine flask, and while stirring at room temperature, 30.03 g of methyl glucose dioleate, 60.01 g of dicaprylyl carbonate, and 3.15 g of the refined jojoba wax / boabo oil solution are added. Finally, the solution is stirred for a further 15 minutes.

[0096] Example 5c: Glyceryl caprylate is heated in a water bath (55–60 °C) to liquefy it before use. A stock solution is prepared from 23.82 g of jojoba wax and 1.20 g of boabo oil. 4.40 g of 2-ethylhexyl laurate are placed in a 20 ml glass container, and while stirring at room temperature, 1.00 g of glyceryl caprylate, 2.02 g of methyl glucose dioleate, 2.01 g of 2,5-dimethyl isosorbide, 0.51 g of isoamyl laurate, and 0.10 g of the refined jojoba wax / boabo oil solution are added. Finally, the solution is stirred for a further 15 minutes.

[0097] Example 5d: A stock solution is prepared from 23.81 g of refined jojoba wax and 1.19 g of boabo oil. 221.85 g of 2-ethylhexyl laurate are placed in a 500 ml iodine flask, and while stirring at room temperature, 60.00 g of methyl glucose dioleate, 15.00 g of dicaprylyl carbonate, and 3.16 g of the refined jojoba wax / boabo oil solution are added. Finally, the solution is stirred for a further 15 minutes.

[0098] Example 5e: A stock solution is prepared from 49.75 g of refined jojoba wax and 0.25 g of boabo oil. 7.00 g of 2-ethylhexyl laurate, 0.50 g of isoamyl laurate, 1.51 g of refined jojoba wax, and 1.00 g of the refined jojoba wax / boabo oil solution are placed in a glass vial at room temperature and stirred for 60 minutes.

[0099]

[0100] Example 6: Addition of further ingredients (surface-active substances, fragrances, water, substances that improve combability and / or reduce viscosity)

[0101] Example 6a: Glyceryl caprylate is heated in a water bath (55–60 °C) to liquefy it before use. 309.5 g of 2-ethylhexyl laurate are placed in an 180° flask, and while stirring at room temperature, 70.07 g of sorbitan monooleate, 420.1 g of glyceryl caprylate, 0.5079 g of boabo oil, 50.32 g of isoamyl laurate, and 10.02 g of refined jojoba wax are added. Finally, 140.1 g of water are added to the solution, and it is stirred for another 15 minutes. Example 6b: Glyceryl caprylate is heated in a water bath (55–60 °C) to liquefy it before use. 159.5 g of 2-ethylhexyl laurate and 170.02 g of silicone oil (1.5 cSt) are added. The mixture is placed in a flask at room temperature, and while stirring, 80.01 g of sorbitan monooleate, 420.3 g of glyceryl caprylate, 0.5025 g of boabo oil, and 10.07 g of refined jojoba wax are added. Finally, 160.1 g of water are added to the solution, and it is stirred for another 15 minutes.

[0102] Example 6c: Glyceryl caprylate is heated in a water bath (55–60 °C) to liquefy it before use. 319.5 g of 2,2-ethylhexyl laurate are placed in an iodine flask, and while stirring at room temperature, 480.0 g of glyceryl caprylate, 0.5027 g of boabo oil, 50.10 g of isoamyl laurate, and 10.03 g of refined jojoba wax are added. Finally, 140.2 g of water are added to the solution, and it is stirred for another 15 minutes. Example 7: Determining effectiveness on crickets

[0103] The efficacy of the preparations according to the invention with regard to their insecticidal effect was initially tested on house crickets (Acheta domesticus) as an experimental animal model. House crickets are readily available in pet stores in reproducible quality and, due to their greater length (averaging 12 mm), are easier to handle and observe than lice. For this investigation, the house crickets were stored at 5°C in a refrigerator, thus reducing their vital functions to a minimum and halting their muscle movement. During this cold torpor, the insects were separated into individual Petri dishes.

[0104] After the crickets have acclimatized to room temperature and their motor function has fully returned, 10 pL each of a positive control (commercial product NYDA express, Pohl-Boskamp, ​​Germany) and the solutions according to the invention are applied to the neck area using an Eppendorf pipette. The time from application until no vital signs are visible to the naked eye is measured with a stopwatch and recorded in seconds.

[0105] Three copies of the positive control and the test solutions are taken. The same positive control is used in every test series. The times of all measurement series are averaged for the positive control. If vital signs are still detectable after five minutes, the insects are killed using the positive control.

[0106] The preparation is considered effective if no vital signs are observed after 180 seconds. This is twice the time required for the positive control.

[0107]

[0108] * Only one cricket was killed within 5 minutes of preparation.

[0109] The results demonstrate the good efficacy of the preparation according to the invention - also in comparison to a product containing isopropyl myristate.

[0110]

[0111]

[0112] The results demonstrate the very good efficacy of the preparations according to the invention. In some samples, the onset of action occurs significantly faster than in the positive control.

[0113] Example 8: Determining effectiveness on body lice

[0114] Body lice (Pediculus humanus humanus) are established and widely used test organisms for investigating the pediculicidal effect of head lice treatments.

[0115] Adult body lice were kept in glass Petri dishes (90 mm diameter, 15 mm height) at 32 °C and 76% relative humidity in the dark until the start of the tests. Humidity was provided by a saturated NaCl solution. Lice (approximately 20 days old) were fed defibrinated rabbit blood using an artificial membrane feeding system immediately before the examination. To evaluate the efficacy of the preparations according to the invention and the positive control (commercial product NYDA express, Pohl-Boskamp, ​​Germany) against adult, mature lice, three replicates were performed with 30 lice each (mixed sexes) using each test product and the negative controls (tap water). An incubation period of 10 minutes was used for all products.The application period began with transferring the lice into a sieve, which was placed in a porcelain dish (70 ml volume) filled with either the test product or, for the controls, tap water. All products were used undiluted. The porcelain dishes were kept in a water bath at 32.1 ± 0.3 °C. Care was taken to ensure that the lice were completely covered with the test solution. After an incubation period of 10 minutes, the test products were washed off with shampoo solution. For this, the sieve containing the lice was first swirled for one minute in a beaker filled with 10 g of ultra-sensitive shampoo (without perfume, artificial colors, preservatives, and silicones; Alverde natural cosmetics, dm-drogerie markt GmbH & Co. KG, Karlsruhe, Germany) and 400 ml of tap water. The lice were then rinsed for another minute with lukewarm water from a spray bottle.Finally, lice were placed on a 4 x 4 cm piece of dark corduroy and stored in an incubator in the dark. The condition of the lice was checked 10 minutes, 1 hour, and 24 hours after the end of the treatment. For this purpose, lice on corduroy were placed in a glass Petri dish on top of a second piece of corduroy, which was placed on a hot plate at 36.3 ± 0.7 °C for 5 minutes.

[0116] During the observations, the behavior and vitality of the lice were categorized as follows:

[0117] State "L": alive and able to walk to a heat source; State "M": unable to walk, small movements observed (moribund); State "G": no reflexes, only bowel movements detectable; State "D": no movements at all (dead)

[0118] The lice were classified as either surviving (lice rated L) or non-surviving (lice rated M, G and D).

[0119] The following table shows the status of the lice at the respective observation times:

[0120]

[0121] The data demonstrate the excellent efficacy of the preparations according to the invention against body lice.

[0122] Example 9: Determining effectiveness on body lice eggs

[0123] Eggs of body lice (Pediculus humanus humanus) are established and widely used test organisms for investigating the ovicidal efficacy of head lice treatments. The lice are adapted to rabbit blood and are reared using an artificial membrane feeding system (Hemotek Membrane Feeding System, Hemotek Ltd, Lancashire, United Kingdom). For egg-laying, adult body lice were fed fresh defibrinated rabbit blood and kept on hair stalks in glass Petri dishes (90 mm × 0.15 mm height, Carl Roth GmbH & Co. KG, Karlsruhe, Germany) at 32 °C and 76% relative humidity (RH) in darkness. The humidity was generated using a saturated NaCl solution according to Winston & Bates (1960). The eggs used for the experiments were 1–3 days old, undamaged, and attached to a hair.

[0124] The application period began with the transfer of the eggs to a sieve, which was placed in a porcelain dish (70 ml volume, Morgan Technical Ceramics Haldenwanger, Waldkraiburg, Germany) filled with the test product or, in the case of controls, with tap water. All products were used undiluted. The porcelain dishes were kept in a water bath at 32 °C. It was ensured that the eggs were completely covered with the test solution. After an exposure time of 2 minutes, the sieve was removed from the porcelain dish and left in a glass Petri dish for a further exposure time of 8 minutes. The test products were then washed with a shampoo solution (1:4, shampoo:tap water). For this, the sieve containing the eggs was first shaken for one minute in a beaker containing 10 g of ultra-sensitive shampoo (without perfume, dyes, preservatives, and silicones; Alverde Naturkosmetik, dm-drogerie markt GmbH & Co. KG).KG, Karlsruhe, Germany) and 40 ml of tap water. The eggs were then washed for another minute with lukewarm water from a wash bottle.

[0125] Finally, the eggs were placed in labeled vials (5 eggs per vial) for observation and stored in an incubator in the dark. All negative control trials were conducted with tap water, but otherwise treated the same as the test eggs.

[0126] To evaluate the efficacy of the provided test products against lice eggs, three replicates were performed with 30 eggs each using each test product, along with positive controls (commercial product NYDA express, Pohl-Boskamp, ​​Germany) and negative controls (water). For all formulations, the positive and negative controls, immersion for 2 minutes followed by an additional 8 minutes of exposure at room temperature was applied. Egg mortality was assessed 12 days after treatment, when the larvae in the negative control had hatched.

[0127] To determine effectiveness, it was established whether:

[0128] - Larvae had hatched: Eggs from which the larvae had completely hatched showed an empty, clear eggshell with a clearly open operculum (hatched).

[0129] - The larvae have not hatched. Three states are distinguished here:

[0130] 1. emergent: Egg with a partially opened operculum, but incomplete eclosion

[0131] 2. early: No hatching has occurred, but the egg surface was still smooth and the operculum was closed.

[0132] 3. late: No hatching has occurred; the egg has shrunk / collapsed.

[0133] The following table shows the status of body lice eggs after treatment with the test products, as well as with a positive and negative control after 12 days. The mortality rate shown is calculated according to the following equation:

[0134] (emergent + early + Zate)

[0135] Mortality = - ■ 100

[0136] 90

[0137] Within the scope of the invention, it was found that preparations according to the invention, which contain less than 1% water, are particularly effective in killing lice eggs.

Claims

Claims 1. Use of 2-ethylhexyl laurate to kill ectoparasites and / or their eggs.

2. Use according to claim 1, characterized in that the 2-ethylhexyl laurate is used in a preparation containing 10-95 wt% 2-ethylhexyl laurate, preferably 70-90 wt%.

3. Use according to one of the preceding claims, characterized in that at least one additional substance is used which kills ectoparasites and / or their eggs.

4. Use according to claim 3, characterized in that the substance is selected from the group of surfactants.

5. Use according to claim 4, characterized in that the surfactant is selected from the group consisting of methyl glycosides or polyols esterified with fatty acids, partial glycerides and mixtures thereof.

6. Use according to claim 5, characterized in that the surfactant(s) are used in a preparation containing 5 - 80 wt.%, preferably 5 - 20 wt.%, surfactants.

7. Use according to claims 4-6, characterized in that the surfactant is Methyl Glucose Dioleate, Sorbitan Sesquicaprylate, Sorbitan Monooleate or Glyceryl Caprylate.

8. Use according to claim 3, characterized in that isoamyl laurate is used, preferably in a preparation containing 1 - 20 wt.%, preferably 1 - 8 wt.% isoamyl laurate.

9. Use according to any one of claims 1 to 7, characterized in that 2-ethylhexyl laurate, methyl glucose diolate and isoamyl laurate are used in a preparation with a viscosity of not more than 100 cSt.

10. Use according to one of the preceding claims, characterized in that further cosmetically or pharmaceutically acceptable substances are used.

11. Use according to claim 10, characterized in that one or more substances are used which improve the combability of hair or the removal of ectoparasites and / or their eggs from the hair.

12. Use according to claim 11, characterized in that dicaprylyl carbonate or 2,5-dimethyl isosorbide is used, preferably in a preparation in a concentration of 0.1 - 30 wt.%, preferably in a concentration of 5 - 20 wt.%.

13. Use according to one of the preceding claims, characterized in that all substances used are present in a preparation.

14. Use according to any of the preceding claims, characterized in that the preparation contains at least one substance which reduces the viscosity and / or improves the sprayability.

15. Use according to claim 14, characterized in that the at least one substance is from the group of short-chain mono- and esters. The dicarboxylic acids are selected with short-chain primary alcohols, preferably diethyl succinate, and water.

16. Use according to claim 14, characterized in that the at least one substance is selected from triglycerides, preferably argan oil, partially hydrogenated rapeseed oil, soybean oil or sesame oil, preferably in a preparation in a concentration of 5 - 30 wt.%, preferably in a concentration of 10 - 20 wt.%.

17. Use according to claim 15 or 16, characterized in that the preparation has a viscosity of not more than 60 mPas.

18. Use according to one of the preceding claims, characterized in that the preparation or preparations contain 0.01 - 2.0 wt.% fragrances.

19. Use according to one of the preceding claims, characterized in that the ectoparasites are lice, preferably head lice.

20. Medical device or drug containing 2-ethylhexyl laurate.

21. Medical device or drug according to claim 20, comprising at least one further substance that kills ectoparasites and / or their eggs, preferably sorbitan sesquicaprylate or methyl glucose dioleate.

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