Cationic liposomes for enhancing skin absorption and their preparation method

Abstract

The present invention provides a method for producing cationic liposomes using a high-pressure emulsification apparatus, cationic liposomes produced by the method, and cosmetic compositions, food compositions, and pharmaceutical compositions containing the cationic liposomes. The method for producing cationic liposomes uses a high-pressure emulsification apparatus to produce liposomes that are safe for the skin without using toxic organic solvents, and enables mass production of liposomes. In addition, the cationic liposomes produced by the method have excellent dosage form stability and are positively charged, which can enhance the skin absorption of active ingredients carried inside. Therefore, the cationic liposomes can be used in cosmetics, foods, medicines, etc.

Description

[Technical field]

[0001] This application claims priority to Korean Patent Application No. 10-2022-0002164, filed on January 6, 2022, the entire specification of which is incorporated herein by reference.

[0002] The present invention relates to a cationic liposome for enhancing dermal absorption of an active ingredient, a cosmetic composition containing the same, and a method for producing the same. [Background technology]

[0003] The skin barrier is composed of lipid molecules filling the extracellular space between stratum corneum cells, and thus plays a very important role in maintaining the homeostasis of the skin and protecting the skin from various external physical stimuli and changes related to hydration / dehydration. However, when delivering an active ingredient into the skin, such a skin barrier acts somewhat disadvantageously. In particular, it is known that the active ingredient is most commonly delivered into the skin via an intercellular pathway, but in the case of a hydrophilic active ingredient, it is even more difficult to pass through such a pathway composed of lipid molecules. Therefore, in order to overcome this, a biocompatible skin delivery system is needed.

[0004] Liposomes are a representative skin delivery medium used to enhance the dermal absorption of active ingredients. They are composed of phospholipids, which are endogenous substances, and have high biocompatibility, making them highly used in the field of cosmetics. In particular, they are characterized by being able to simultaneously carry hydrophilic and lipophilic substances, which is advantageous for the dermal delivery of various active ingredients. In addition, they can stably carry the active ingredients in a bi-layer structure or multi-layer structure, and can be applied to various cosmetic formulations, including not only emulsion formulations but also solubilized formulations with a transparent appearance. Liposomes can be prepared into elastic liposomes, polymer-coated liposomes, cationic liposomes, etc., depending on the components of the membrane. Among them, cationic liposomes are liposomes with a positive zeta potential, and can more easily approach the skin due to electrostatic attraction with the negatively charged skin surface, which is useful for enhancing the dermal absorption of the active ingredients.

[0005] For the production of liposomes, it is most important to evaluate the stability and whether the efficacy of the active ingredient carried therein is well exhibited when applied to an actual dosage form. The most basic method for producing liposomes is through a thin film hydration method, but there are limitations in terms of stability and mass production. Recently, a manufacturing method using a microfluidizer (MF) for producing liposomes has been reported. However, when producing liposomes through the microfluidizer, it is difficult to produce bi-layer or multi-layer particles, which are the particle morphology unique to liposomes. Therefore, when confirming the morphology of the liposomes produced in this way and when applying them to a dosage form, it is necessary to confirm through efficacy evaluation whether they actually contribute to the skin delivery of the active ingredient. Summary of the Invention [Problem to be solved by the invention]

[0006] One embodiment provides a method for producing cationic liposomes using a high-pressure emulsification device.

[0007] Another aspect provides a cationic liposome produced by the above method.

[0008] Yet another aspect provides a cosmetic composition comprising the cationic liposome.

[0009] Yet another embodiment provides a skin external preparation composition comprising the cationic liposome.

[0010] Yet another aspect provides a pharmaceutical composition comprising said cationic liposome.

[0011] Yet another aspect provides a food composition comprising said cationic liposomes. [Means for solving the problem]

[0012] One embodiment provides a method for producing cationic liposomes using a high-pressure emulsification device. The method includes the steps of preparing a first solution containing a phospholipid, a ceramide, and cholesterol, stirring a mixture of the first solution and a second solution containing a cation donor, and preparing cationic liposomes from the stirred mixture using a high-pressure emulsifier.

[0013] In the conventional liposome production method, the thin film hydration method has a problem that an organic solvent is used, making mass production difficult. In contrast, the cationic liposome production method according to the above embodiment uses a high-pressure emulsification apparatus, so that no organic solvent is required and mass production is easy.

[0014] The method includes preparing a first solution that includes a phospholipid, a ceramide, and a cholesterol.

[0015] The first solution may be prepared by dissolving the components contained in the first solution by heating at a temperature of 60 to 90°C, 60 to 85°C, 60 to 80°C, 65 to 90°C, 65 to 85°C, 65 to 80°C, 70 to 90°C, 70 to 85°C, or 70 to 80°C.

[0016] The phospholipid is a type of lipid that contains polar phosphate and non-polar fatty acid, and is a major component of biological membranes. The phospholipid may be a natural phospholipid or a synthetic phospholipid. The phospholipid may be lecithin, hydrogenated lecithin, phosphatidylcholine (PC), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidic acid (PA), phosphatidylinositol (PI), egg phosphatidylcholine (EPC), egg phosphatidylglycerol (EPG), egg phosphatidylethanolamine (EPE), egg phosphatidylserine (EPE ...ethanolamine (EPE), egg phosphatidylethanolamine (EPE), egg phosphatidylethanolamine (EPE), egg phosphatidylethanolamine (EPE), egg phosphatidylethanolamine (EPE), egg phosphatidylethanolamine (EPE), egg phosphatidylethanolamine (EPE), egg phosphatidylethanolamine (EPE), egg phosphatidylethanolamine (E PS), egg phosphatidic acid (EPA), egg phosphatidylinositol (EPI), soy phosphatidylcholine (SPC), soy phosphatidylglycerol (SPG), soy phosphatidylethanolamine (SPE), soy phosphatidylserine (SPS), soy phosphatidic acid (SPA), soy phosphatidylinositol (SPI), dipalmitoylphosphatidylcholine (DPPC), 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC ), dimyristoyl phosphatidylcholine (DMPC), dipalmitoyl phosphatidylglycerol (DPPG), dioleoyl phosphatidylglycerol (DOPG), dimyristoyl phosphatidylglycerol (DMPG), hexadecylphosphocholine (HEPC), hydrogenated soy phosphatidylcholine (HSPC), distearoyl phosphatidylcholine (DSPC), distearoyl phosphatidylglycerol (DSPG), dioleoyl phosphatidylethanolamine dioleoylamine (DOPE), palmitoylstearoylphosphatidylcholine (PSPC), palmitoylstearoylphosphatidylglycerol (PSPG), monooleoylphosphatidylethanolamine (MOPE), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC), polyethylene glycol distearoylphosphatidylethanolamine (PEG-DSPE), dipalmitoylphosphatidylserine (DPPS), 1,The phospholipid may be, but is not limited to, 2-dioleoyl-sn-glycero-3-phosphatidylserine (DOPS), dimyristoyl phosphatidylserine (DMPS), distearoyl phosphatidylserine (DSPS), dipalmitoyl phosphatidic acid (DPPA), 1,2-dioleoyl-sn-glycero-3-phosphatidic acid (DOPA), dimyristoyl phosphatidic acid (DMPA), distearoyl phosphatidic acid (DSPA), dipalmitoyl phosphatidylinositol (DPPI), 1,2-dioleoyl-sn-glycero-3-phosphatidylinositol (DOPI), dimyristoyl phosphatidylinositol (DMPI), distearoyl phosphatidylinositol (DSPI), or a combination thereof. The phospholipid may be hydrogenated lecithin.

[0017] The phospholipid may be present in an amount of 0.1 to 5.0% by weight, 0.1 to 4.0% by weight, 0.1 to 3.0% by weight, 0.1 to 2.0% by weight, 0.1 to 1.0% by weight, 0.1 to 0.7% by weight, 0.3 to 5.0% by weight, 0.3 to 4.0% by weight, 0.3 to 3.0% by weight, 0.3 to 2.0% by weight, 0.3 to 1.0% by weight, 0.3 to 0.7% by weight, 0.4 to 2.0% by weight, 0.4 to 1.0% by weight, 0.4 to 0.7% by weight, or 0.4 to 0.6% by weight based on the total weight of the cationic liposome.

[0018] The ceramide can be, but is not limited to, ceramide NS, ceramide AS, ceramide EOS, ceramide NDS, ceramide ADS, ceramide EODS, ceramide NP, ceramide AP, ceramide EOP, ceramide NH, ceramide AH, ceramide EOH, or combinations thereof.

[0019] The ceramide may be contained in an amount of 0.001 to 0.5 wt%, 0.001 to 0.1 wt%, 0.005 to 0.5 wt%, 0.005 to 0.1 wt%, 0.01 to 0.5 wt%, 0.01 to 0.1 wt%, or 0.01 to 0.05 wt% based on the total weight of the cationic liposome. The amount of the ceramide may be selected within an appropriate range by a person skilled in the art to enhance similarity to living skin.

[0020] The weight ratio of the phospholipid and the cholesterol may be 5:1 to 1:1, 4.5:1 to 1.5:1, 4:1 to 1.5:1, 3.5:1 to 1.5:1, 3:1 to 1.5:1, 2.5:1 to 1.5:1, 4.5:1 to 2:1, 4:1 to 2:1, 3.5:1 to 2:1, 3:1 to 2:1, 2.5:1 to 2:2, or 2:1. If the content of the cholesterol is too low compared to the content of the phospholipid (e.g., the weight ratio of the phospholipid and the cholesterol is 5:1) or is equal to or higher than the content of the phospholipid (e.g., the weight ratio of the phospholipid and the cholesterol is 1:1), phase separation or a suspension phenomenon may occur. Thus, the weight ratio of the phospholipid and the cholesterol may be less than 5:1 or more than 1:1. By using the above weight ratio of phospholipid and cholesterol, it is possible to obtain bi-layer or multi-layer particles, which are particle morphologies unique to liposomes, even when using a liposome preparation method using a high-pressure emulsifier. In one embodiment, it was confirmed that when the weight ratio of phospholipid and cholesterol is 2:1, the particle size and zeta potential remained stable at room temperature for more than 5 weeks without change.

[0021] The cholesterol may be contained in an amount of 0.1 to 5.0% by weight, 0.1 to 4.0% by weight, 0.1 to 3.0% by weight, 0.1 to 2.0% by weight, 0.1 to 1.0% by weight, 0.1 to 0.5% by weight, 0.1 to 0.4% by weight, 0.1 to 0.3% by weight, 0.2 to 5.0% by weight, 0.2 to 4.0% by weight, 0.2 to 3.0% by weight, 0.2 to 2.0% by weight, 0.2 to 1.0% by weight, 0.2 to 0.5% by weight, 0.2 to 0.4% by weight, or 0.2 to 0.3% by weight based on the total weight of the cationic liposome. If the cholesterol content is outside the above range, the membrane stability of the liposome may be reduced.

[0022] The first solution may include a solvent capable of dissolving phospholipids, cholesterol, and ceramide. The first solution may further include a polyol. The first solution may further include dipropylene glycol. The dipropylene glycol may be used to dissolve lipid moieties or oily substances. The dipropylene glycol may be included in an amount of 5 to 20% by weight, 5 to 15% by weight, 5 to 12% by weight, 8 to 20% by weight, 8 to 15% by weight, 8 to 12% by weight, or 10% by weight based on the total weight of the cationic liposome, but is not limited thereto. The first solution may further contain an additional component that does not substantially affect the physical properties of the cationic liposomes. The content of the additional component may be appropriately selected by a person skilled in the art within a range that does not substantially affect the physical properties of the cationic liposomes according to the purpose.

[0023] The first solution may be composed of, but is not limited to, hydrogenated lecithin, cholesterol, ceramide, and dipropylene glycol. The method includes stirring a mixture of the first solution with a second solution that includes a cation donor.

[0024] The second solution may contain a cation donating substance so that the liposomes finally produced will carry a positive charge (+). The cation donor may be, for example, laurdimonium hydroxypropyl hydrolyzed wheat protein, guar hydroxypropyltrimonium chloride, polyquaternium-7, polyquaternium-10, polyquaternium-11, polyquaternium-22, polyquaternium-51, polyquaternium-67, polyquaternium-80, cocamidopropylamine oxide, stearamidopropyl dimethylamine, behentrimonium chloride, polyquaternium-51, polyquaternium-67, polyquaternium-80 ... The cation donating material may be one or more selected from the group consisting of, but not limited to, cationic polysaccharides, polysaccharides of natural origin, and chitosan. The cation donating material may be a cationic polysaccharide. The cationic polysaccharide may be a natural polysaccharide or a synthetic polysaccharide. The cation donating material may be chitosan.

[0025] The cation donor may be present in an amount of more than 0.01% by weight, more than 0.01 to 5.0% by weight, more than 0.01 to 4.0% by weight, more than 0.01 to 3.0% by weight, more than 0.01 to 2.0% by weight, 0.05% by weight or more, 0.05 to 5.0% by weight, 0.05 to 4.0% by weight, 0.05 to 3.0% by weight, 0.05 to 2.0% by weight, 0.05 to 1.5% by weight, 0.05 to 1.0% by weight, 0.05 to 0.5% by weight, 0.05 to 0.2% by weight, or 0.05 to 0.1% by weight, based on the total weight of the cationic liposome. When the cation donor is present in an amount of 0.01% by weight or less based on the total weight of the cationic liposome, the zeta potential of the liposome is also negative (-), thereby resulting in an anionic liposome. Therefore, the cation donor is preferably contained in an amount exceeding 0.01% by weight based on the total weight of the cationic liposome. When the cation donor is contained in an amount of 0.05% by weight or more based on the total weight of the cationic liposome, a cationic liposome having a zeta potential of 20 mV or more can be obtained. The second solution may include a solvent capable of dissolving a cation donor. The second solution may include a hydrophilic solvent. For example, the hydrophilic solvent may be water (e.g., distilled water), but is not limited thereto.

[0026] The second solution may further include butylene glycol. The inclusion of butylene glycol may improve the solubility of the components carried in the liposome and / or improve skin moisturizing power. The butylene glycol may be included in an amount of, but is not limited to, 5 to 20% by weight, 5 to 15% by weight, 5 to 12% by weight, 8 to 20% by weight, 8 to 15% by weight, 8 to 12% by weight, or 10% by weight based on the total weight of the cationic liposome.

[0027] The second solution may further include a hydrophilic active ingredient. The hydrophilic active ingredient may be a skin functional active ingredient. The skin functionalities may be, but are not limited to, skin whitening, moisturizing, skin barrier strengthening, anti-oxidation, anti-inflammation, anti-aging, wrinkle improvement, skin soothing, etc. The hydrophilic active ingredient may be any known active ingredient, without being limited to its type. For example, the hydrophilic active ingredient may be niacinamide. The content of the hydrophilic active ingredient may be appropriately selected by a person skilled in the art, taking into consideration the type and purpose of the ingredient, within a range that does not substantially affect the physical properties of the cationic liposome. Specifically, the hydrophilic active ingredient may be contained in an amount of 0.001 to 30% by weight, 0.001 to 20% by weight, or 0.001 to 10% by weight based on the total weight of the cationic liposome. For example, when the hydrophilic active ingredient is niacinamide, the niacinamide may be present in an amount of, but is not limited to, 0.001 to 30% by weight, 0.001 to 20% by weight, 0.001 to 15% by weight, 0.01 to 30% by weight, 0.01 to 20% by weight, 0.01 to 15% by weight, 0.1 to 30% by weight, 0.1 to 20% by weight, 0.1 to 15% by weight, 1 to 30% by weight, 1 to 20% by weight, or 1 to 15% by weight based on the total weight of the cationic liposome.

[0028] The second solution may further contain an additional component that does not substantially affect the physical properties of the cationic liposomes. The content of the additional component may be appropriately selected by a person skilled in the art within a range that does not substantially affect the physical properties of the cationic liposomes according to the purpose.

[0029] The stirring may be performed while gradually adding or mixing the first solution into the second solution.

[0030] The stirring may be carried out at room temperature, for example, 15 to 35°C, 15 to 30°C, 20 to 35°C, or 20 to 30°C.

[0031] The stirring may be performed at 1,500 to 3,500 rpm, 1,500 to 3,000 rpm, 2,000 to 3,500 rpm, or 2,000 to 3,000 rpm. The stirring may be performed for 30 seconds to 30 minutes, 30 seconds to 20 minutes, 30 seconds to 10 minutes, 30 seconds to 5 minutes, 1 minute to 30 minutes, 1 minute to 20 minutes, 1 minute to 10 minutes, or 1 minute to 5 minutes.

[0032] The stirring can be carried out by a common method, for example, by using a homomixer.

[0033] The method includes producing cationic liposomes from the stirred mixture using a high pressure emulsifier.

[0034] In the step of preparing the cationic liposomes, the stirred mixture may be subjected to high pressure emulsification using a high pressure emulsification device. The high-pressure emulsification device is not limited to a specific type as long as it is a known device, and may be, for example, a microfluidizer (MF) or a high-pressure homogenizer.

[0035] The pressure condition of the high pressure emulsifier may be 800 to 1,500 bar, 800 to 1,200 bar, 800 to 1,100 bar, 800 to 1000 bar, 900 to 1,500 bar, 900 to 1,200 bar, 900 to 1,100 bar, 900 to 1,000 bar, 1,000 to 1,500 bar, 1,000 to 1,200 bar, 1,000 to 1,100 bar, or 1,000 bar. If the pressure is too low, nanoparticles are not formed properly. If the pressure is too high, excessive physical force may be applied, resulting in a decrease in stability.

[0036] The high pressure emulsifier may be applied under conditions of 2 cycles or more, 3 cycles or more, 2 to 5 cycles, 2 to 4 cycles, 3 to 5 cycles, or 3 cycles.

[0037] When cationic liposomes are produced under the pressure and cycle conditions of the high-pressure emulsification device, cationic nanoliposomes with excellent formulation stability can be obtained. When the cationic liposomes are prepared under the pressure and cycle conditions of the high-pressure emulsifier, bi-layer or multi-layer particles, which are particle morphologies specific to liposomes, can be obtained.

[0038] The cationic liposomes are prepared using a high-pressure emulsifier, so that the preparation process is safe without using toxic organic solvents, and allows for mass production of liposomes.

[0039] Another aspect provides a cationic liposome produced by the method according to the previous aspect.

[0040] The cationic liposomes prepared by the method may be non-toxic since no toxic organic solvents are used in the preparation process. In one embodiment, the cationic liposomes prepared by the method and the cosmetic composition containing the same were confirmed to be non-irritating and safe for the skin based on a skin irritation index evaluation. Therefore, the cationic liposomes may be safely used in cosmetics, foods, medicines, etc.

[0041] The particle size of the cationic liposomes can be 50-300nm, 50-250nm, 100-300nm, 100-250nm, 150-300nm, 150-250nm, 200-300nm, or 200-250nm. The average particle size of the cationic liposomes can be 200-250nm. Therefore, the cationic liposomes can be nanoliposomes. The cationic liposomes are nano-sized, so they also have excellent skin penetration efficacy.

[0042] The zeta potential of the cationic liposome may be 20 to 50 mV, 20 to 45 mV, 25 to 50 mV, or 25 to 40 mV. The cationic liposome is positively charged (+) and therefore can be effectively adsorbed to the negatively charged (-) skin surface by utilizing electrostatic attraction, thereby improving the skin absorption of the skin active ingredient carried in the liposome.

[0043] The cationic liposomes also have excellent formulation stability, since the particle size and zeta potential are well maintained even after storage at room temperature for 5 weeks or more.

[0044] The cationic liposome may have a bi-layer or multi-layer structure. The cationic liposome may be a mixture of a bi-layer liposome and a multi-layer liposome. In one embodiment, the cationic liposome was confirmed to have a morphology specific to bi-layer or multi-layer liposomes, even though it was prepared using a high-pressure emulsifier.

[0045] The cationic liposome may be liposomes carrying a skin functional active ingredient. The skin functional active ingredient may be a hydrophilic active ingredient. The skin functional active ingredient may be, but is not limited to, niacinamide. In one embodiment, it was confirmed that when niacinamide is carried in the cationic liposomes and delivered to the skin, the amount of change in skin brightness, the amount of change in melanin, and the amount of change in melasma are significantly increased compared to when niacinamide is included in the composition without using the cationic liposomes and delivered to the skin. Therefore, the cationic liposome may be liposomes with enhanced skin absorption ability of the skin functional active ingredient carried in the liposomes.

[0046] Another aspect provides a composition comprising a cationic liposome.

[0047] The composition may be a composition for delivering an active ingredient carried in a cationic liposome. Specifically, the composition may be a composition for delivering an active ingredient carried in a cationic liposome to the skin.

[0048] The composition may comprise 0.001 to 50% by weight, 0.001 to 40% by weight, 0.001 to 30% by weight, 0.001 to 20% by weight, 0.01 to 50% by weight, 0.01 to 40% by weight, 0.01 to 30% by weight, 0.01 to 20% by weight, 0.1 to 50% by weight, 0.1 to 40% by weight, 0.1 to 30% by weight, or 0.1 to 20% by weight of the cationic liposomes based on the total weight of the composition. In one embodiment, the composition may be a cosmetic composition.

[0049] The cosmetic composition may further contain, in addition to the active ingredients disclosed herein, ingredients and functional additives that are generally used in cosmetic compositions, such as, for example, common adjuvants such as antioxidants, stabilizers, solubilizers, surfactants, dispersants, thickeners, moisturizers, preservatives, vitamins, pigments, and fragrances, and cosmetically acceptable carriers.

[0050] The cosmetic composition may be manufactured in any commonly manufactured formulation. For example, the cosmetic composition may have a cosmetic formulation such as lotion, cream, extract, cleansing foam, cleansing water, pack, ampoule, body lotion, body oil, body gel, shampoo, rinse, hair conditioner, hair gel, foundation, lipstick, mascara, or makeup base.

[0051] In one embodiment, the composition may be a skin topical composition.

[0052] The skin topical preparation may be a cream, gel, ointment, skin emulsion, skin suspension, transdermal delivery patch, drug-containing bandage, lotion, or a combination thereof. The skin topical preparation may be appropriately mixed with ingredients commonly used in skin topical preparations such as cosmetics and medicines, such as aqueous ingredients, oily ingredients, powder ingredients, alcohols, moisturizers, thickeners, UV absorbers, whitening agents, preservatives, antioxidants, surfactants, fragrances, colorants, various skin nutrients, or combinations thereof, as necessary.

[0053] In one embodiment, the composition may be a food composition. The food composition may be a functional health food composition.

[0054] The health functional food composition may be used by itself or together with other foods or food ingredients, and may be used appropriately by a general method. The amount of the active ingredient mixed may be appropriately determined depending on the purpose of use (preventive, health or therapeutic treatment). There is no particular limitation on the type of the health functional food. In the type of health functional food, the beverage composition may contain various flavoring agents or natural carbohydrates as additional ingredients in addition to a normal beverage. The natural carbohydrates are monosaccharides such as glucose and fructose; disaccharides such as maltose and sucrose; and polysaccharides such as dextrin and cyclodextrin; as well as sugar alcohols such as xylitol, sorbitol, and erythritol. As the sweetener, natural sweeteners such as thaumatin and stevia extract, and synthetic sweeteners such as saccharin and aspartame may be used. The health functional food composition may also include nutrients, vitamins, electrolytes, flavors, colorants, pectic acid and its salts, alginic acid and its salts, organic acids, protective colloid thickeners, pH regulators, stabilizers, preservatives, glycerin, alcohol, carbonation agents used in carbonated beverages, or combinations thereof. The health functional food composition may also include fruit pulp for the production of natural fruit juice, fruit juice beverages, vegetable beverages, or combinations thereof.

[0055] In one embodiment, the composition may be a pharmaceutical composition.

[0056] The pharmaceutical composition may further comprise a pharma- ceutically acceptable diluent or carrier. The diluent may be lactose, corn starch, soybean oil, microcrystalline cellulose or mannitol, and the lubricant may be magnesium stearate, talc, or a combination thereof. The carrier may be an excipient, disintegrant, binder, lubricant, or a combination thereof. The excipient may be microcrystalline cellulose, lactose, low-substituted hydroxycellulose, or a combination thereof. The disintegrant may be calcium carboxymethylcellulose, sodium starch glycolate, calcium dihydrogen phosphate anhydrous, or a combination thereof. The binder may be polyvinylpyrrolidone, low-substituted hydroxypropylcellulose, hydroxypropylcellulose, or a combination thereof. The lubricant may be magnesium stearate, silicon dioxide, talc, or a combination thereof. The pharmaceutical composition can be formulated into an oral or parenteral dosage form. The oral dosage form can be granules, powders, liquids, tablets, capsules, dry syrups, or combinations thereof. The parenteral dosage form can be an injection.

[0057] In consideration of the complexity of this specification, overlapping content has been omitted, and terms not specifically defined in this specification have the meanings commonly used in the technical field to which the present invention belongs. Effect of the Invention

[0058] According to one embodiment of the method for producing cationic liposomes, a high-pressure emulsification apparatus is used, and liposomes that are safe for the skin can be produced without using toxic organic solvents, making it possible to mass-produce liposomes.

[0059] In addition, the cationic liposomes prepared by the above method have excellent formulation stability and are positively charged, which can enhance the skin absorption of the active ingredient contained therein, and therefore can be used in cosmetics, foods, medicines, etc. [Brief description of the drawings]

[0060] [Figure 1] 1 shows the results of measuring the change in particle size (nm) of the cationic liposomes of Example 2-2 5 weeks after production.

[0061] [Diagram 2] 1 shows the results of measuring the change in zeta potential (mV) of the cationic liposome of Example 2-2 5 weeks after production.

[0062] [Diagram 3] 1 shows the particle structure of the cationic liposome of Example 2-2.

[0063] [Figure 4] 1 is a graph showing skin brightness (L-value) after use of the extract formulations of the comparative example and the preparation example.

[0064] [Diagram 5] 1 is a graph showing the change in skin brightness after use of the extract formulations of the comparative example and the manufacturing example.

[0065] [Figure 6] 1 is a graph showing the melanin index (MI) after use of the extract formulations of the comparative example and the preparation example.

[0066] [Figure 7] 1 is a graph showing the change in skin melanin after use of the extract formulations of the comparative example and the manufacturing example.

[0067] [Figure 8] The results show the results of confirming skin melasma (mm2) after use of the extract formulations of the comparative example and the manufacturing example.

[0068] [Figure 9] 1 is a graph showing the change in skin melasma after use of the extract formulations of the comparative example and the manufacturing example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0069] The present invention will be described in more detail below with reference to examples. However, these examples are for illustrative purposes only and the scope of the present invention is not limited to these examples.

[0070] Example 1. Evaluation of physical properties of cationic liposomes depending on chitosan content Cationic liposomes with different chitosan contents were prepared and their zeta potentials were measured.

[0071] First, cationic nanoliposomes were prepared using the components and contents (wt%) shown in Table 1. The cationic liposomes of Examples 1-1 to 1-5 differ only in the chitosan contents.

[0072] The specific manufacturing method is as follows. Phase A, which is composed of lecithin and dipropylene glycol, was heated to 70-80°C and dissolved. Phase A was gradually added to the room temperature aqueous phase B, which contained chitosan, and stirred for 5 minutes at 2,000 to 3,000 rpm with a homomixer. After the first stirring, the mixture was subjected to high-pressure emulsification treatment at 1,000 bar, 3 cycles, to finally produce liposomes.

[0073] [Table 1]

[0074] Next, the zeta potential of cationic liposomes according to the chitosan content was measured. A dynamic light scattering (DLS: dynamic light scattering (SZ-100 HORIBA)) was used as the measuring device. The zeta potential measurement results of cationic liposomes according to the chitosan content are shown in Table 2.

[0075] [Table 2]

[0076] As shown in Table 2, the zeta potential of cationic liposomes not containing chitosan (Example 1-1) was -34.9 mV. As the chitosan content increased, the zeta potential also increased, but when the chitosan content was 0.1 wt% or more, the zeta potential did not increase significantly any more. Therefore, in the production of cationic liposomes, the chitosan content was set to 0.05 wt% and further experiments were carried out.

[0077] Example 2. Evaluation of physical properties of cationic liposomes according to cholesterol content Cationic liposomes were prepared with a fixed chitosan content and different cholesterol contents, and their particle size and zeta potential were measured to evaluate their stability.

[0078] First, cationic liposomes were prepared using the same method as in Example 1 and the components and contents (wt%) in Table 3 below. The cationic liposomes of Examples 2-1 to 2-3 differ only in the cholesterol contents. Ceramide and cholesterol were used to enhance similarity to the living body and skin safety. Since cholesterol is known to help improve the membrane stability of liposomes, different cholesterol contents were used to prepare the liposomes.

[0079] [Table 3]

[0080] Next, the stability was confirmed by visual evaluation immediately after production and after 3 days of storage at room temperature. As a result of visual evaluation, when the cholesterol content was much lower than that of lecithin or was the same as that of lecithin (Examples 2-1 and 2-3), phase separation or a suspending phenomenon in which the color became blurred occurred. In addition, the cationic liposome of Example 2-2 did not separate phases and did not undergo a suspending phenomenon.

[0081] Therefore, the particle size and zeta potential of the cationic liposomes of Example 2-2 were measured using a dynamic light scattering device immediately after production and every week during the 5-week storage at room temperature.

[0082] FIG. 1 shows the results of measuring the change in particle size (nm) of the cationic liposomes of Example 2-2 5 weeks after production.

[0083] FIG. 2 shows the results of measuring the change in zeta potential (mV) of the cationic liposome of Example 2-2 5 weeks after production.

[0084] As shown in FIG. 1 and FIG. 2, the particle size and zeta potential of the cationic liposome of Example 2-2, in which the weight ratio of lecithin to cholesterol is 2:1, are stable for 5 weeks.

[0085] In addition, in the manufacturing method of Example 1, cationic liposomes of Examples 2-1 to 2-3 were manufactured by changing only the high-pressure emulsification conditions, and an experiment was carried out to measure the particle size of the resulting liposomes. The high-pressure emulsification conditions were set to three types as follows: (i) 1,000 bar, 1 cycle, (ii) 1,000 bar, 3 cycles, and (iii) 1,000 bar, 5 cycles.

[0086] Using a statistical program, particle size was compared and it was found that there was a significant difference between cycles 1 and 3, but not between cycles 3 and 5. Therefore, it was confirmed that high-pressure emulsification condition (ii) was the most suitable.

[0087] Experimental Example 1. Analysis of particle structure of cationic liposomes The particle structure of the cationic liposome of Example 2-2 was analyzed. Cryogenic transmission electron microscopy (Cryo-TEM) was used to analyze the structure of the prepared cationic liposome particles. Cryo-TEM is suitable for confirming the bi-layer or multi-layer structure of liposome particles because it maintains the sample at an ultra-low temperature and allows observation of the original morphology and structure. The specific analysis method is as follows. 5 μL of the cationic liposomes of Example 2-2 were loaded onto a 200 mesh carbon lacey film Cu-grid, and then immersed in ethane (about -170°C) liquefied by a Vitrobot and plunge frozen (plunge freeze). The prepared frozen sample was observed with a Cryo-TEM (Tecnai F20 (FEI)) at an accelerating voltage of 200 kV or less.

[0088] FIG. 3 shows the particle structure of the cationic liposome of Example 2-2.

[0089] As shown in Figure 3, the cationic liposomes of Example 2-2 had a particle size of about 100 to 300 nm. In addition, it was confirmed that the bi-layer structure and multi-layer structure, which can be said to be characteristic of liposomes, were mixed and formed.

[0090] Example 3. Preparation of cationic liposomes 10% by weight of niacinamide was loaded onto the cationic liposome of Example 2-2, which was confirmed to have the best stability among Examples 1 and 2. Specifically, the cationic liposome was prepared using the same method as in Example 1 and the components and contents (by weight) in Table 4 below.

[0091] [Table 4]

[0092] Production Examples and Comparative Examples: Production of Cationic Liposome-Containing Extract As a preparation example, a cosmetic composition in the form of an extract was prepared containing the cationic liposome of Example 3. The cationic liposome of Example 3 contains 10% by weight of niacinamide, so the cosmetic composition in the form of an extract containing 20% ​​by weight of the cationic liposome ultimately contains about 2% by weight of niacinamide.

[0093] As a comparative example, a cosmetic composition in the form of an extract containing 2% by weight of niacinamide instead of cationic liposomes was prepared.

[0094] The ingredients and contents (wt%) of the extract-form cosmetic compositions of the Preparation Examples and Comparative Examples are shown in Table 5 below.

[0095] [Table 5]

[0096] Experimental example 2. Skin safety evaluation A skin safety evaluation was carried out for the cationic liposome of Example 3 and the extract formulations of the Production Examples and Comparative Examples.

[0097] Specifically, the cationic liposome of Example 3 and the extract formulations of the Preparation Example and Comparative Example were evaluated for irritation levels in 20 adult men and women without skin diseases as follows. 20 μL of the sample was applied to the forearm of the tester, and the test site was sealed and applied for 24 hours. After removing the patch, 30 minutes and 24 hours later, the skin reaction was examined based on the terminology presented in the CTFA (The Cosmetic, Beauty and Fragrance Association) guidelines. The primary irritation index (PII) scores of the testers obtained according to the evaluation criteria were averaged, and if it was less than 1, it was evaluated as low irritation, if it was less than 2, it was evaluated as mild irritation, if it was less than 3.5, it was evaluated as medium irritation, and if it was 3.5 or more, it was evaluated as strong irritation. The results are shown in Table 6 below.

[0098] [Table 6]

[0099] As a result, as shown in Table 6, it was confirmed that the cationic liposomes of Example 3 and the extract formulations of the Preparation Examples and Comparative Examples were all non-irritating and could be safely used in products.

[0100] Experimental Example 3. Evaluation of whitening efficacy The extract formulations of the Preparation Example (containing cationic liposomes) and the Comparative Example (not containing cationic liposomes) each contain 2% by weight of niacinamide, an active whitening ingredient. Therefore, the high whitening effect when using each formulation can be seen as a more efficient delivery of the active ingredient into the skin. To evaluate the whitening efficacy of the extract formulations of the Preparation Example and the Comparative Example, measurements were carried out on three items: skin brightness, skin melanin, and skin melasma.

[0101] Specifically, 21 female subjects (ages 36-58, average age 50.048) were asked to use the comparative and example products on half of the face (half-test), twice a day (morning / evening) for four weeks. To measure skin brightness, melanin, and melasma, the changes in each value after two weeks of use and after four weeks of use were measured compared to before use.

[0102] (1) Improves skin brightness Skin brightness was measured by photographing the front of the face using Mark-Vu (PSIPLUS CO., LTD, Korea) and analyzing the skin brightness value (L-value) of the test area using the I-Max plus program for the photographed image. The higher the L-value, the more improved the skin brightness.

[0103] Figure 4 is a graph showing skin brightness (L-value) after use of the extract formulations of the comparative example and the manufacturing example. Figure 5 is a graph showing the change in skin brightness after use of the extract formulations of the comparative example and the manufacturing example.

[0104] As shown in FIG. 4 and FIG. 5, the preparation example showed about 1.5 times better skin brightness improving effect than the comparative example.

[0105] (2) Efficacy of reducing skin melanin Skin melanin was measured using a Mexameter MX18 (Courage Khazaka electroni, Germany) to measure the melanin value, which indicates color. The lower the MI (melanin index) value, the more improved the skin melanin is.

[0106] Fig. 6 is a graph showing the melanin index (MI) after use of the extract formulations of the comparative example and the manufacturing example. Fig. 7 is a graph showing the change in skin melanin after use of the extract formulations of the comparative example and the manufacturing example.

[0107] As shown in FIG. 6 and FIG. 7, the Preparation Example has a more excellent effect of reducing skin melanin than the Comparative Example.

[0108] (3) Efficacy in improving melasma on the skin Skin melasma was measured using Antera 3D CS (Miravex, Ireland) using the Melanin-Hyperconcentration analysis mode to measure the affected area (mm 2 The more melasma was improved, the more the affected area (mm 2 ) value is reduced.

[0109] FIG. 8 shows the results of the skin melasma (mm 2 9 is a graph showing the change in melasma on the skin after use of the extract formulations of the comparative example and the production example.

[0110] As shown in FIG. 8 and FIG. 9, the Preparation Example showed a higher melasma improving effect than the Comparative Example.

[0111] Considering the results of Experimental Example 3, the skin brightness change amount, melanin change amount, and melasma change amount of the Preparation Example showed significant differences after 2 weeks and 4 weeks of use compared to the Comparative Example. Through this, it can be seen that the whitening effect was better when niacinamide was loaded into the cationic liposome of Example 3. This can be seen as being because the cationic liposome delivered the active ingredient better into the skin. Therefore, it can be seen that the cationic liposome of Example 3 has excellent skin delivery effect of the loaded active ingredient.

Claims

1. preparing a first solution comprising phospholipids, ceramide and cholesterol; agitating a mixture of a second solution containing a cation donor and the first solution; and producing cationic liposomes from the stirred mixture using a high-pressure emulsification apparatus.

2. The method of claim 1 , wherein the phospholipid is hydrogenated lecithin.

3. 2. The method of claim 1, wherein the weight ratio of said phospholipid and said cholesterol is from 4.5:1 to 1.5:

1.

4. 2. The method of claim 1, wherein the cholesterol is present in an amount of 0.1 to 5.0% by weight based on the total weight of the cationic liposome.

5. The method of claim 1 , wherein the cation donating material is chitosan.

6. 2. The method of claim 1, wherein the cationic donor is present in an amount of from more than 0.01 to 5.0% by weight based on the total weight of the cationic liposome.

7. The method according to claim 1, wherein the pressure condition of the high pressure emulsifier is 800 to 1,500 bar.

8. A cationic liposome produced by the method according to any one of claims 1 to 7.

9. 2. The cationic liposome of claim 1, wherein the particle size of the cationic liposome is 50 to 300 nm.

10. The cationic liposome according to claim 1 , wherein the zeta potential of the cationic liposome is from 20 to 50 mV.

11. The cationic liposome of claim 1 , wherein the cationic liposome has a bilayer or multilayer structure.

12. A cosmetic composition comprising the cationic liposome according to claim 8.

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