Composition with increased solubilizing power comprising a polyol- and carboxylic acid-based solvent

Abstract

The invention relates to a composition with increased solubilizing power comprising a solvent and a biologically active compound to be solubilized. The invention is characterized in that the solvent contains a mixture of: - at least one polyol, taken alone or in combination, having a Hansen parameter δH of between 18 and 30 MPa^0.5; and - at least one carboxylic acid, taken alone or in combination; - wherein the ratio of the number of hydroxyl group(s) to the number of carboxylic acid group(s) in the mixture is between 3 -CH2OH for 1 -COOH and 8 -CH2OH for 1 -COOH; and - the average molecular weight of the mixture is less than 130 g·mol⁻¹, and the active compound has Hansen parameters δD of between 17 and 22 MPa^0.5, δP of between 2 and 18 MPa^0.5 and δH of between 4 and 42 MPa^0.5, respectively.

Description

[0001] Composition with increased solubilizing power comprising a polyol-based solvent and carboxylic acid

[0002] TECHNICAL FIELD

[0003] The invention relates to a cosmetic and / or pharmaceutical composition comprising a solvent based on at least one polyol and at least one carboxylic acid, and a cosmetically and / or pharmaceutically active compound. It has applications in the development of cosmetic, nutraceutical, and pharmaceutical products.

[0004] The cosmetics, nutraceutical, and pharmaceutical industries face several technical challenges when formulating natural products (instability, incompatibility, and limited solubility). Furthermore, these industries must consider expectations regarding sustainability and environmental impact, leading to a growing demand for environmentally friendly solvents in product formulations and a rejection of conventional preservative systems.

[0005] Indeed, the solvents and preservative systems traditionally used in such products often present warnings, or even proven risks to the environment and health due to their toxicity and non-biodegradability.

[0006] The industry now demands products that are not only healthy and environmentally friendly, but also more effective. Effective solvents must improve the solubility and stability of active ingredients and contribute to the sensory properties of finished cosmetic or pharmaceutical products.

[0007] A number of active ingredients, whether water-soluble or fat-soluble, pose stability and solubility problems in conventional matrices.

[0008] Cosmetic and pharmaceutical active ingredients consist of hydrophilic or lipophilic molecules that exhibit pharmacological or cosmetic activity when applied topically in a suitable matrix. Traditionally, these active ingredients are solubilized within binary systems such as emulsions. However, some active ingredients incorporated into these matrices present solubilization or stability problems over time.

[0009] In particular, the most effective antioxidants are also known to be the most fragile. To circumvent this problem, manufacturers often use chemical forms that are less susceptible to degradation, but also less effective, or they use overdoses to compensate for the loss of active ingredient over time.

[0010] They can also resort to developing costly encapsulation technologies.

[0011] Thus, today, if a manufacturer needs to solubilize both water-soluble and fat-soluble active ingredients, the available solutions include:

[0012] the formulation of these 2 entities in an emulsion or microemulsion; or encapsulation.

[0013] However, these two chemical matrices have major drawbacks:

[0014] The emulsion is a thermodynamically unstable system, whose kinetics must be evaluated; and

[0015] Microemulsion is a thermodynamically stable system, but requires formulation constraints which prevent certain applications (presence of surfactants in very high proportions, presence of co-surfactants which are sometimes irritating such as ethanol...).

[0016] Furthermore, encapsulation is a complex and expensive process that is not suitable for all types of active ingredients.

[0017] Most active ingredients (natural or otherwise) are very fragile and their effectiveness can be significantly reduced or even eliminated if they are not stabilized within the formula. Numerous parameters influence this stability, and the importance of each depends on the type of active ingredient.

[0018] Illustrative examples include the following active ingredients covering very distinct physicochemical properties: 4-n-butylresorcinol, retinol and retinoids in general, niacinamide, vitamin C.

[0019] 4-n-butylresorcinol (4-nBR) or rucinol, is a valuable ingredient for brightening skin and reducing pigmentation, thus contributing to an even skin tone and improved skin appearance.

[0020] However, its low solubility, poor stability, and potential to irritate the skin limit its optimal use. Researchers have notably found that a nanoemulsion of 4-nBR improves the solubility and stability of 4-nBR while significantly reducing its skin irritation (Shao W. et al., “Enhanced stability and reduced irritation of 4-n-butylresorcinol via nanoemulsion formulation: Implications for skin pigmentation treatment”, European Journal of Medicinal Chemistry. 2024, Vol.

[0021] 279).

[0022] Retinoids, defined as synthetic or natural derivatives of vitamin A, have been extensively studied as anti-aging molecules and are widely used in cosmetics and pharmaceuticals. In cosmetics, only retinol is permitted, at a maximum concentration set in Europe at 0.3%.

[0023] However, due to their physicochemical properties, retinoids are highly unstable and extremely sensitive to light (UV), oxygen, and temperature (Sumrall L. et al., "Stability of retinol in liposomes as measured by fluorescence lifetime spectroscopy and ELIM," BBA Advances, 2023, Vol. 18; Zhong J. et al., "Topical retinoids: Novel derivatives, nano lipid-based carriers, and combinations to improve chemical instability and skin irritation," Journal of Cosmetic Dermatology, 2024, Vol. 23, 10). Furthermore, topical application of retinoids often results in skin irritation. These instabilities and irritant properties of retinoids limit their use in both cosmetic and pharmaceutical products. To overcome these drawbacks, various strategies are being explored (microencapsulation, metal chelators, addition of antioxidant vitamins, use of retinol derivatives, etc.).) have been tested, but they often result in a decrease in the biological activity of the product (Temova Rakusa Z. et al., “Retinoid stability and degradation kinetics in commercial cosmetic products”, Journal of cosmetic dermatology. 2021, Vol. 20, 7).

[0024] In finished cosmetic products, retinol tends to degrade rapidly over time. A decrease of 25% to 79% in the retinol concentration of several serums has been shown as early as 30 days after opening the container (Maggadani BP et al., “RETINOL STABILITY IN ANTI-AGING FACE SERUM POST-OPENING PERIOD,” International Journal of Applied Pharmaceutics, 2024, Vol. 16, 4). The most significant decrease was observed in samples stored in transparent containers and exposed to light, with a reduction of 79% and an average weekly decrease of 17%. It should be noted that, according to these researchers, the secondary transfer of the product to different packaging accelerated the degradation.

[0025] Retinol also appears to be unstable under UV light and heat, which limits its effectiveness in cosmetic formulations (Sumrall et al., 2023; Temova Rakusa et al., 2021).

[0026] Niacinamide is another widely used cosmetic active ingredient that can degrade into niacinamide N-oxide and then into nicotinic acid, which can become irritating under various conditions (Thomas S. et al., "Quantification of potential impurities by a stability indicating UV-HPLC method in niacinamide active pharmaceutical ingredient," Journal of Pharmaceutical and Biomedical Analysis, 2012, Vol. 60). High pH, ​​UV exposure, or high temperature promote the degradation of niacinamide (Zhen-ming Chen, "Study on the stability of niacinamide and its mixed system," Detergent & Cosmetics, 2022, Vol. 45, 5).

[0027] Taking vitamin G as an example, the most active form is ascorbic acid, which is very susceptible to degradation, particularly in aqueous formulations. Vitamin G in its acidic form (L-ascorbic acid) degrades rapidly into dehydroascorbic acid and then into inactive compounds (Sheraz MA et al, “Stability and stabilization of ascorbic acid,” Househ. Pers. Care Today. 2015, Vol. 10): at 30°C, only 20% of the initial concentration may remain after 4 months (Sheraz MA et al., “Factors affecting formulation characteristics and stability of ascorbic acid in water-in-oil creams,” International Journal of Cosmetic Science. 2014, Vol. 36, 5). This observation led to the use of other forms of vitamin G (ester form for example, palmytilascorbate or methylascorbate), although these show a lower biological activity (Pinnell, SR et al., “Topical L-ascorbic acid: percutaneous absorption studies”, Dermatol. Surg., 2001, Vol. 27).This degradation is sensitive to environmental conditions, particularly the type of matrix (emulsion, aqueous solution, etc.), pH, temperature, and the presence of oxygen or metal ions such as Cu2+, Fe2+, or Zn2+. Specifically, incorporating vitamin C into a microemulsion, as well as a more acidic pH, appears to promote its stability at 20°C and 45°C (Gallarate M. et al., "On the stability of ascorbic acid in emulsified systems for topical and cosmetic use," International Journal of Pharmaceutics, 1999, Vol. 188, 2). Finally, its dissolution in glycerin seems to enhance its stability (Kim S. et al., "Stabilization of L-ascorbic acid in cosmetic emulsions," Journal of Industrial and Engineering Chemistry, 2018, Vol. 57).

[0028] PREVIOUS TECHNIQUE

[0029] Numerous efforts have therefore been undertaken to develop solvents and formulations capable of solubilizing and stabilizing cosmetic and pharmaceutical active ingredients. These often fragile active ingredients require suitable matrices to preserve their efficacy while preventing degradation. Approaches primarily rely on emulsions, nanoemulsions, or specific biocompatible solvents, but these solutions still have limitations in terms of solubility, stability, compatibility with different types of active ingredients (water-soluble and oil-soluble), and efficacy.

[0030] Biocompatible solvents based on fatty acid esters for cosmetic applications have been studied (Esipovich et al., 2024, "A Comprehensive Study on Physicochemical Properties of Fatty Acid Esters Derived from Vegetable Oils and Alcohols"). This study explores the properties of fatty acid esters derived from vegetable oils and alcohols. These compounds exhibit excellent solubilization capabilities for certain active ingredients. However, their application remains limited to molecules with similar chemical affinities, and these solvents therefore do not allow the simultaneous solubilization of hydrophilic and lipophilic active ingredients.

[0031] Short-chain vegetable oil-derived polyols have also been studied (Estrada et al., 2024, "Sequestration of Methylene Blue Dye Using Coconut-Oil-Derived Polyols"). Coconut oil polyols show an ability to solubilize hydrophilic dyes. Although biocompatible, their performance is limited to specific hydrophilic molecules, and no broad cosmetic or pharmaceutical applications have been explored.

[0032] 2,5-Furandicarboxylic acid (FDCA) is presented as a renewable polycarboxylic acid used to stabilize emulsions and improve the solubility of certain active ingredients (Yang et al., 2024, "2,5-Furandicarboxylic Acid (FDCA): A Bio-Based Solubilizer"). However, the use of FDCA remains primarily focused on stabilizing thermodynamically unstable emulsions, and its versatility, particularly with a variety of active ingredients, does not appear to have been demonstrated. Plant-derived polyols improve the stability of nanoemulsions containing cosmetic actives. These solvents show potential for anti-aging and moisturizing formulations (Arik et al., 2025, "Green Innovations with Plant-Derived Biocompatible Compounds"). However, they are specific to nanoemulsions and do not simplify homogeneous-phase formulations.

[0033] Several studies focus on solvent mixtures to improve solubilization properties. A mixture of lactic acid and glycerol at a molar ratio of 1:4 forms an effective solvent for essential oils of Thymus vulgaris and Origanum vulgare or olive oil (Freitas David et al., 2025, "NADES-in-Oil Emulsions Enriched with Essential Oils for Cosmetic Application"), extracts of lavender, thyme, oregano, cork, garlic or lemon (Freitas David et al., 2022, "Green Extraction of Cork Bioactive Compounds Using Natural Deep Eutectic Mixtures"), and even phenols and terpenoids, which are useful in cosmetics (Freitas David et al., 2024, "Developing translucent emulsions using sustainable NADES-based extracts"). In addition, a mixture of ethylene glycol or glycerol, with oxalic acid or maleic acid, forms an effective solvent for extracting wood biomass, including lignin (Yang Jiyou et al., 2023, “Mild pretreatment with Bronsted acidic deep eutectic solvents for fractionating [beta]-O-4 linkage-rich lignin with high sunscreen performance and evaluation of enzymatic saccharification synergism” and patent CN114108350B).

[0034] The implementation of solutions based on polyols and / or carboxylic acids thus shows significant limitations, particularly with a dependence on multi-phase systems (emulsions, nano-emulsions).

[0035] Current approaches do not always succeed in obtaining a solvent capable of solubilizing and stabilizing the active ingredients over time and against environmental factors such as light, oxygen, or temperature variations.

[0036] Solvents are thus generally optimized for a specific type of active ingredient (water-soluble or fat-soluble), without offering the flexibility required for broad solubilization.

[0037] They may require high concentrations of active ingredients to maintain their effectiveness, thus increasing the risk of skin irritation or side effects.

[0038] They also often require additional stabilizers to keep active ingredients in solution, making these formulations thermodynamically unstable and requiring complex adjustments.

[0039] TECHNICAL PROBLEM

[0040] Considering the above, one problem that the present invention aims to solve is to develop new cosmetic and / or pharmaceutical products comprising a new solvent system offering superior solubilization, stability over time, both of the vehicle (solvent system) and of the active ingredients, in order to maintain their effectiveness, and advantageously to improve the compatibility of hydrophilic and lipophilic active ingredients with each other and therefore the flexibility in the choice of active ingredients used, while keeping an appropriate galenic formulation without dependence on complex and unstable multi-phase systems.

[0041] Surprisingly, and contrary to theoretical predictions, an innovative approach based in particular on Hansen parameters has identified a new solvent system consisting of polyol(s) and carboxylic acid(s), which, mixed in specific proportions, allows for the solubilization of effective doses of cosmetically and / or pharmaceutically active compounds, simultaneously solubilizing water-soluble and fat-soluble actives, with performance superior to traditional systems, while stabilizing them.

[0042] BENEFITS PROVIDED

[0043] The invention is distinguished by its ability to stabilize complex systems and solubilize a wide variety of active ingredients, from simple molecules to peptides, while ensuring exceptional homogeneity and thermodynamic stability.

[0044] Advantageously, the solvents obtained do not exhibit phase change, in particular no recrystallization, over a wide temperature range between -25°C and +45°C for a period of at least 6 months.

[0045] Using Hansen's parameters, it is theoretically possible to define a solubilization range for active ingredients in a given matrix. However, the solvent system according to the invention exceeds the expected limits of this theoretical model by experimentally demonstrating a much broader solubilization capacity than predicted by the model.

[0046] The solvents developed according to the invention are indeed capable of solubilizing active ingredients with very different solubility parameters (water-soluble and fat-soluble), which is not anticipated according to classical predictions of Hansen parameters. This constitutes a technological breakthrough, as it pushes back the theoretical limits usually accepted by those skilled in the art for similar solvents.

[0047] In addition to their solubilizing capacity, the solvents used in the invention offer a unique advantage by stabilizing the active ingredients over time, reducing their chemical or oxidative degradation. For example, the most effective antioxidants are also known to be the most fragile. The object of the invention thus makes it possible to avoid using chemical forms that are less susceptible to degradation but also less effective in circumventing this problem, or to avoid overdosing during manufacturing. Taking the more specific example of vitamin C, the most active form is ascorbic acid, which is very susceptible to degradation; therefore, a more stable but less effective ester form (ascorbyl palmitate) is often used.

[0048] Unlike traditional solvents commonly used in the past, which often rely on thermodynamically unstable emulsion systems or specific solvents limited to a single type of active ingredient (water-soluble or oil-soluble), the solvents according to the invention offer exceptional compatibility with molecules possessing diverse properties. This simplifies the formulation obtained according to the invention compared to complex, multi-active ingredient formulations of the prior art. As a result, formulations based on the solvents according to the invention do not require additional emulsifiers to maintain the active ingredients in solution, thereby reducing costs, simplifying the manufacturing process, and improving thermodynamic stability.

[0049] The solvent system according to the invention makes it possible to broaden the solubility limits of the active ingredients used to obtain better efficacy; thanks to the efficiency of the solvents, the active ingredients can be used at reduced concentrations while retaining their efficacy, also improving the safety profile of the product (better benefit / risk), in particular by limiting the risks of skin irritation or side effects by avoiding unnecessary overdosing, especially for irritating active ingredients.

[0050] The object of the invention also allows for an economic gain, as the formulations obtained require less raw material to achieve the same effects.

[0051] Furthermore, by stabilizing the active ingredients and limiting their degradation, the invention helps reduce waste related to oxidation or loss of product efficacy, thus enhancing their durability. In addition, the solvents are formulated from polyols and carboxylic acids, ingredients often of natural or renewable origin, aligning the invention with green chemistry objectives.

[0052] The invention thus represents a potentially major advance in the field of solvents for industries including cosmetics, pharmaceuticals, and food, by combining versatility, efficiency, stability, and durability.

[0053] TECHNICAL SOLUTION

[0054] The solution to this problem primarily involves a cosmetic and / or pharmaceutical composition comprising

[0055] a solvent containing a mixture of:

[0056] o at least one polyol, taken alone or in combination, having a Hansen 6H parameter between 18 and 30 MPa^0.5, and o at least one carboxylic acid, taken alone or in combination,

[0057] ■ in which the ratio between the number of hydroxyl group(s) -CH2OH (primary alcohol) in the mixture and the number of carboxylic acid group(s) -COOH in the mixture is between 3 -CH2OH for 1 -COOH and 8 -CH2OH for 1 -COOH, and

[0058] ■ The average molecular mass of said mixture is less than 130 g·mol -1 ,

[0059] and at least one cosmetically and / or pharmaceutically active compound with Hansen parameters respectively 6D between 17 and 22 MPa^0.5, 6P between 2 and 18 MPa^0.5 and 6H between 4 and 42 MPa^0.5, characterized in that the composition comprises a combination of at least one fat-soluble active and at least one water-soluble active.

[0060] It also relates to the use of a composition claimed according to the invention, in which the active compound is a cosmetically active compound for the care of the skin and hair, to improve well-being or bodily or oral hygiene.

[0061] Finally, the invention relates to a composition claimed according to the invention, in which the active compound is a pharmaceutically active compound for its use as a medicinal product.

[0062] The invention and its resulting advantages will be better understood upon reading the description and non-limiting embodiments that follow.

[0063] DESCRIPTION OF IMPLEMENTATION METHODS

[0064] The invention relates to a cosmetic and / or pharmaceutical composition comprising both:

[0065] a solvent containing a mixture of:

[0066] o at least one polyol, taken alone or in combination, having a Hansen 6H parameter between 18 and 30 MPa^0.5, and o at least one carboxylic acid, taken alone or in combination,

[0067] ■ in which the ratio between the number of hydroxyl group(s) -CH2OH (primary alcohol) and the number of carboxylic acid group(s) -COOH in the mixture is between 3 -CH2OH for 1 -COOH and 8 -CH2OH for 1 -COOH, and

[0068] ■ The average molecular mass of said mixture is less than 130 g·mol -1 ,

[0069] and at least one cosmetically and / or pharmaceutically active compound with Hansen parameters respectively 6D between 17 and 22 MPa Q.5, 6P between 2 and 18 MPa Q.5 and 6H between 4 and 42 MPa Q.5.

[0070] The invention is characterized in that the composition comprises a combination of at least one fat-soluble active ingredient and at least one water-soluble active ingredient.

[0071] By "lipid-soluble," we mean a compound with a preferential affinity for lipid or nonpolar organic media, resulting in significantly higher solubility in oily or slightly polar organic solvents than in water. A compound is classified as lipophilic when its solubility in a lipophilic solvent is greater than its aqueous solubility, and in particular when its octanol / water partition coefficient (logP), measured using a standardized equilibrium partitioning method, is positive and advantageously greater than 1. The terms lipophilic, hydrophobic, and nonpolar are used interchangeably. By "water-soluble," we mean a compound with a preferential affinity for water, resulting in significant and stable solubility in aqueous media, allowing the formation of a homogeneous solution on a macroscopic scale.A compound is classified as water-soluble when its solubility in water is greater than its solubility in a reference lipophilic solvent and / or when its octanol / water partition coefficient (logP), measured using a standardized equilibrium partitioning method, is negative. The terms water-soluble, hydrophilic, lipophobic, and polar are used interchangeably.

[0072] LogP represents the decimal logarithm of the ratio of the concentrations of the compound in two immiscible phases, octanol and water, at equilibrium. The classic "shake-flask" method involves mixing an excess of the compound with a water / octanol mixture, shaking until equilibrium is reached, then separating the phases and quantifying the concentration of the compound in each using appropriate analytical techniques (UV-visible, HPLC, or mass spectrometry). A negative logP indicates that the compound preferentially distributes in the aqueous phase, confirming its water-soluble nature. A positive logP indicates that the compound preferentially distributes in the octanol phase, confirming its lipid-soluble nature.

[0073] The Hansen parameters are determined at a reference temperature of approximately 25°C, at atmospheric pressure. The determination of the Hansen parameters is carried out according to a methodology generally accepted in the field, using standard protocols, such as those described, for example, in the reference works of C.M. Hansen.

[0074] The solvent mixture used in the composition according to the invention is a mixture comprising therefore at least one polyol, taken alone or in combination, having a Hansen parameter δH between 18 and 30 MPa^0.5, preferably between 20 and 25 MPa^0.5, and at least one carboxylic acid, according to the ratio and molecular mass claimed according to the invention.

[0075] Polyols and carboxylic acids were selected based on their availability, biocompatibility and functionality, taking into account their durability, biodegradability and ability to improve the performance of cosmetic, nutraceutical and pharmaceutical products.

[0076] The polyol, taken alone or in combination, preferably used in the composition according to the invention is chosen from 1,3-propanediol, 1,2-propanediol, 1,5-pentanediol, glycerol, sorbitol, erythritol, pentaerythritol, threitol, galactitol, more preferably from 1,3-propanediol, 1,5-pentanediol, glycerol, even more preferably from 1,3-propanediol.

[0077] Propanediol, particularly 1,3-propanediol, is a polyol widely used in cosmetic formulations due to its moisturizing and solvent properties. It is derived from renewable sources (such as corn fermentation), making it a viable and sustainable alternative to petroleum-based glycols.

[0078] 1,5-Pentanediol is another linear polyol obtained by fermentation. It can contribute to the sensory qualities of cosmetics, ensuring smooth textures.

[0079] The polyol most preferably used in the composition according to the invention is 1,3-propanediol.

[0080] By "carboxylic acid," we mean a monocarboxylic acid or a polycarboxylic acid.

[0081] The carboxylic acid, taken alone or in combination, preferably used in the composition according to the invention is chosen from succinic acid, citric acid, tartaric acid, malic acid, lactic acid, adipic acid, itaconic acid, 2,5-furandicarboxylic acid, citramalic acid, glutaric acid, D-mannonic acid, 3-hydroxybutyric acid, trihydroxyglutaric acid, galacturonic acid, 3-hydroxypropionic acid, 2-hydroxyglutaric acid, fumaric acid, D-malic acid, oxalic acid, betaine, more preferably succinic acid, citric acid, tartaric acid, oxalic acid, betaine, lactic acid, even more preferably citric acid, or succinic acid taken alone or in combination with tartaric acid.

[0082] In particular, advantageously, the carboxylic acid is a monocarboxylic acid chosen from lactic acid, 3-hydroxybutyric acid, 3-hydroxypropionic acid, galacturonic acid, D-mannonic acid, betaine, more preferably betaine, or lactic acid.

[0083] In particular, advantageously, the carboxylic acid is a polycarboxylic acid selected from succinic acid, citric acid, tartaric acid, malic acid, adipic acid, itaconic acid, 2,5-furandicarboxylic acid, citramalic acid, glutaric acid, trihydroxyglutaric acid, 2-hydroxyglutaric acid, fumaric acid, D-malic acid, oxalic acid, more preferably succinic acid, citric acid, tartaric acid, oxalic acid, even more preferably citric acid, or succinic acid taken alone or in combination with tartaric acid.

[0084] Succinic acid is a natural, biodegradable, and non-toxic carboxylic acid. It improves the properties of solvents and thus enhances the stability of active ingredients.

[0085] Citric acid is used as a weak organic acid in cosmetics for its chelating properties and its ability to adjust pH. It is generally derived from citrus fruits and is known for its biodegradability.

[0086] Tartaric acid is a carboxylic acid, derived from grapes and other natural sources, used to improve the texture and stability of cosmetic formulations, especially at low temperatures. The carboxylic acid preferably used is citric acid or succinic acid taken alone or in combination with tartaric acid.

[0087] Essentially, the composition according to the invention comprises a ratio between said polyol, taken alone or in combination, and said carboxylic acid, wherein the number of hydroxyl group(s) -CH2OH (primary alcohol) and the number of carboxylic acid group(s) -COOH in the mixture is between 3 -CH2OH for 1 -COOH and 8 -CH2OH for 1 -COOH, and the average molecular mass of said mixture is less than 130 g-mol -1 .

[0088] Preferably, the ratio between the number of hydroxyl group(s) -CH2OH (primary alcohol) and the number of carboxylic acid group(s) -COOH in the mixture is between 4 -CH2OH for 1 -COOH and 6 -CH2OH for 1 -COOH, more preferably 6 -CH2OH for 1 -COOH.

[0089] Preferably, the average molecular mass of said mixture (polyol(s) / carboxylic acid(s)) is between 100 and 120 g·mol -1 .

[0090] Preferably, the solvent mixture used according to the invention does not contain more than two polyols, taken in combination with a maximum of two carboxylic acids.

[0091] Advantageously, the solvent mixture used according to the invention contains a polyol and a carboxylic acid, or a polyol and two carboxylic acids, or two polyols and a carboxylic acid.

[0092] According to advantageous embodiments of the invention, the solvent mixture used according to the invention contains, for example, respectively:

[0093] 1,3-propanediol / succinic acid / tartaric acid, in a ratio of 12 / 1 / I; 1,5-pentanediol / succinic acid / glycerol, in a ratio of 3 / 1 / 3;

[0094] 1,5-pentanediol / oxalic acid / 1,3-propanediol, in a ratio of 3 / 1 / 3; 1,3-propanediol / succinic acid, in a ratio of 6 / 1;

[0095] 1,3-propanediol / citric acid, in a ratio of 6 / 1; glycerol / betaine, in a ratio of 2 / 1; or

[0096] glycerol / lactic acid, in a ratio of 4 / 1.

[0097] The composition according to the invention preferably comprises the mixture of solvents at a concentration between 50% and 99.99%, preferably between 80% and 99.99%, by weight relative to the total weight of the composition.

[0098] Essentially, the composition according to the invention comprises at least one cosmetically and / or pharmaceutically active compound having Hansen parameters respectively δD between 17 and 22 MPa^0.5, preferably δD = 18-19 MPa^0.5, δP between 2 and 18 MPa^0.5, preferably δP = 5-12 MPa^0.5 and δH between 4 and 42 MPa^0.5, preferably δH = 5-26 MPa^0.5.

[0099] The active ingredient is preferably a fat-soluble and / or water-soluble compound chosen from among retinoids such as retinol, ascorbic acid, niacinamide, rucinol, caffeine, quercetin, resveratrol, menthol, copper peptide (GHK-Cu), ferulic acid, a plant extract comprising polar and nonpolar molecules such as Centella asiatica extract, palmitoyl tripeptide, in combination.

[0100] In particular, and advantageously, the fat-soluble active ingredient is chosen from among retinoids such as retinol, rucinol, quercetin, resveratrol, menthol, ferulic acid, palmitoyl tripeptide, and a plant extract comprising polar and nonpolar molecules such as an extract of Centella asiatica, taken alone or in combination.

[0101] Similarly, advantageously, the water-soluble active ingredient is chosen from ascorbic acid, niacinamide, caffeine, copper peptide (GHK-Cu), and a plant extract comprising polar and nonpolar molecules such as an extract of Centella asiatica, taken alone or in combination.

[0102] Advantageously, and as an alternative, the active ingredient is a cosmetically and / or pharmaceutically active plant extract, comprising polar and nonpolar molecules, and in particular an extract of Centella asiatica, said extract comprising a variety of polar and nonpolar molecules. This plant extract, for example, of Centella asiatica, is therefore to be considered as an active ingredient that is both water-soluble and fat-soluble.

[0103] By derivative, we mean a compound that may have structural differences compared to the base compound but has the same physicochemical properties as the base compound and has comparable cosmetic / therapeutic activity.

[0104] Essentially, the composition includes several active ingredients, more specifically a combination of at least one fat-soluble active ingredient and at least one water-soluble active ingredient.

[0105] The composition according to the invention preferably comprises the active ingredient at a concentration of between 0.01% and 20%, preferably between 0.1% and 10%, by weight of the total weight of the composition.

[0106] Preferably, the composition according to the invention is liquid (or viscous) and has a viscosity between 1 mPa.s and 8000 mPa.s, in particular at temperatures between -40°C and +45°C, in particular at temperatures below 0°C, for example between -4°C and -40°C, for example in the order of -20°C.

[0107] Advantageously, the composition according to the invention is homogeneous and does not change phase, for example at temperatures between -40°C and +45°C.

[0108] The term "liquid" or viscous refers to a physical state of matter in which the formulation exhibits the ability to flow under the influence of gravity, without retaining a fixed shape, and adapts to the shape of its container. At a given temperature below 0°C, in its current state down to -40°C, and under standard atmospheric pressure (1 atm), the formulation does not exhibit a rigid, crystalline, or stable amorphous structure characteristic of the solid state. The formulation is considered liquid if its dynamic viscosity, measured according to a standard protocol such as ISO 3104, is below a threshold allowing observable macroscopic flow, generally less than 10 5 mPa.s (milliPascal-second). This property distinguishes the liquid from a solid or semi-solid state at the temperature considered.

[0109] The composition according to the invention is preferably in a form suitable for topical or oral application.

[0110] Preferably, the composition according to the invention is in a form chosen from serums, gels, lotions, mists or biphasic products.

[0111] The composition according to the invention may also include a physiologically acceptable medium, which means a medium that is compatible and suitable for use in contact with human and animal cells, in particular with skin, mucous membranes and / or hair, without toxicity, irritation, undue allergic response and the like, and proportionate to a reasonable benefit / risk ratio.

[0112] A physiologically acceptable medium according to the invention may include any excipient known and used in the cosmetic and / or pharmaceutical field, compatible with the composition according to the invention.

[0113] Naturally, a person skilled in the art will take care to choose any compound(s) to be added to the composition according to the invention in such a way that the advantageous properties inherent in the present invention are not, or are not substantially, altered by the proposed addition. Their concentration will also be chosen so as not to impair the advantageous properties of the compositions according to the invention.

[0114] For example, compounds such as stabilizers, pH adjusters, emulsifiers, and / or solubilizing agents can be advantageously used to improve the properties of the solvent mixture used in the compositions. The choice of these compounds is based on their durability, effectiveness, and compatibility with the desired formulation.

[0115] Another object of the invention relates to the use of a composition according to the invention, in which the active compound is a cosmetically active compound for the care of the skin and hair, to improve well-being or personal or oral hygiene; perfumes may be cited as an example of a compound that can improve well-being.

[0116] By "well-being" we mean a noticeable improvement in the user's overall comfort level resulting from the use of the composition, particularly in terms of a feeling of relaxation, comfort and / or a reduction of a feeling of discomfort.

[0117] The invention also relates to a composition according to the invention, in which the active compound is a pharmaceutically active compound for its use as a medicinal product. EXAMPLES

[0118] The present invention will now be illustrated by means of the following examples:

[0119] Example 1: Method for preparing a mixture of solvents used in a composition according to the invention

[0120] The experimental setup for synthesizing the solvent mixture used in a composition according to the invention and testing its solubilizing power is simple, emphasizing ease of use and practicality. A minimal amount of equipment was used to produce a 1 kg batch, and the operating conditions can be readily scaled up to industrial production.

[0121] At least one polyol preferably chosen from 1,3-propanediol, 1,5-pentanediol, glycerol, and at least one carboxylic acid preferably chosen from succinic acid, citric acid, tartaric acid, oxalic acid, betaine, lactic acid, are mixed in stoichiometric proportions, namely in a ratio of between 3-CH2OH for 1-COOH and 8-CH2OH for 1-COOH.

[0122] The mixtures are heated in a reactor according to a progressive temperature gradient up to 80°C on a hot plate under continuous stirring (mechanical stirrer or shear mixer) until a clear and homogeneous liquid is formed.

[0123] By way of illustration, a solvent used according to the invention (solvent 3) is synthesized as follows: 456.6 g of 1,3-propanediol, 75.05 g of tartaric acid, and 59.05 g of succinic acid are introduced into a closed 1 L reactor. The reaction system is heated using a hot plate and stirred by a motor equipped with a turbine-type stirring blade. The mixture is heated to 80°C for 22 hours. The resulting liquid remains stable at 45°C, 25°C, and -20°C for 6 months.

[0124] Another solvent used according to the invention (solvent 1) is, for example, synthesized as follows: 45.66 g of 1,3-propanediol and 11.81 g of succinic acid are introduced into a 100 mL flask equipped with a condenser. The reaction system is heated using a hot plate and stirred with a magnetic stir bar. The mixture is heated to 70°C for 12 hours. The resulting liquid remains stable at 45°C, 25°C, and -20°C for 6 months.

[0125] The synthesis of the solvent mixture according to the invention requires adherence to a fairly strict temperature cycle. However, it is possible to interrupt and then resume these temperature cycles without affecting the final result of the synthesis. Table 1: Examples of solvents used according to the invention

[0126] Name Function Function Function

[0127] COMPOUND 1 CH2OH COMPOUND COOH in COMPOUND COOH in

[0128] in 2 compound 2 3 compound 3 Ratio (1 / 2 / 3) compound 1

[0129] Solvent 1 1.3- 2 Acid 2 - succinic propanediol - 6 / 1 Solvent 2 1.3- 2 Acid 3 - - citric propanediol 6 / 1 Solvent 3 1.3- 2 Acid 2 Acid 2

[0130] Propanediol, succinic acid, tartaric acid 12 / 1 / 1 Solvent 4 1.5- 2 Acid 2

[0131] Pentanediol Oxalic acid 6:1 Solvent 5 Glycerol 2 Acid 2

[0132] Succinic 6 / 1 Solvent 6 1.3- 2 0 Acid

[0133] propanediol Glycerol 2

[0134] Succinic acid 2 / 4 / 1 Solvent 7 Glycerol 2 Acid 1

[0135] Lactic acid 4 / 1 Solvent 8 Glycerol 2 Betaine 1 2 / 1

[0136]

[0137] Stability was assessed by visual inspections and by microscopic observation (for crystallization, phase separation, decolorization) at -20°C, at room temperature (+20°C) and in an oven at +45°C for a given time.

[0138] The results obtained are compiled in Table 2 below.

[0139] Table 2: Stability results for various solvents, and in particular for various solvents according to the invention (1-6, see Table 1)

[0140] Name 30 days 30 days 30 days -+45°C 180 days 180 days +20°C 180 days -20°C +20°C -20°C +45°C Solvent 1 Stable Stable Stable Stable Stable Stable Solvent 2 Stable Stable Stable Stable Stable Stable Solvent 3 Stable Stable Stable Stable Stable Stable Stable Solvent 4 Stable Stable Stable Stable Stable Stable Solvent 5 Stable Stable Stable Stable Stable Stable Solvent 6 Stable Stable Stable Stable Stable Stable Solvent 7 Stable Stable Stable Stable Stable Stable Solvent 8 Stable Stable Stable Stable Stable Water Crystallization Stable Stable Crystallization Stable Stable Sweet Almond Oil Crystallization Stable Stable Crystallization Stable Stable

[0141]

[0142] Example 2: Solubilization test of different compositions according to the invention, by comparison with known solvents

[0143] Solubilization tests of various active ingredients in different solvents were carried out. The tested active ingredients were solubilized by magnetic stirring in a volume of between 10 and 20 mL of solvent, respectively different solvents used according to the invention (1-3, see Table 1), compared with other commonly known and used cosmetic solvents. The mixtures were stirred at 25°C for 1 to 8 hours until a homogeneous mixture was obtained, and the results regarding solubilization power are presented in Table 3 below.

[0144] Table 3:

[0145] Solvents (% w / w) References (% w / w)

[0146] Oil Active ingredients Solvent 1 Solvent 2 Solvent 3 Water Propylene

[0147] Sweet almond glycol Niacinamide 18.8 21.6 20.9 38.8 9.7 5.0 Vitamin C (acid

[0148] ascorbic acid) 9.7 6.7 9.9 28.4 5.2 5.2 Vitamin A (retinol) 0.5 0 0.4 0 0.1 Not tested Butyl resorcinol

[0149] (rucinol) 4.8 >60 4.8 1.5 4.8 Not tested GHK-C 8.6 4.9 0 4.53 5 0.1

[0150]

[0151] u

[0152] The reference solvents used were, respectively, an amphiphilic solvent (i.e., propylene glycol) and a polar solvent (water) to solubilize polar molecules (e.g., niacinamide and vitamin C), or a nonpolar solvent (sweet almond oil) to solubilize nonpolar molecules (e.g., vitamin A and butyl resorcinol). Since a polar molecule is necessarily very soluble in a polar solvent such as water (and vice versa), some solubilizations were intentionally not tested.

[0153] The Hansen parameters of the assets thus tested are shown in Table 4 below.

[0154] Table 4:

[0155] Active ingredients δD δP δH Solubility (solvents (MPa^0.5) (MPa^0.5) (MPa^0.5) 1, 2 and 3) Tocopherol 16.9 1.5 3.6 No

[0156] Retinol (vitamin A) 17.4 2.2 4.6 Yes

[0157] Ascorbic acid 18 11.7 25.5 Yes

[0158] (vitamin C)

[0159] Niacinamide 19.9 15.1 12.8 Yes

[0160] Rucinol (Butyl resorcinol) 18.5 5.6 10.4 Yes

[0161] Copper Peptide (GHK- 18.2 17.5 14.4 Yes

[0162] Cu)

[0163] Ferulic acid 19.3 8.0 14.8 Yes

[0164] Matrixyl (palmitoyl 17.4 17.2 10.9 Yes

[0165]

[0166] peptide)

[0167] The solvent mixture used according to the invention is distinguished by its ability to stabilize complex systems and to solubilize a wide variety of active ingredients, from simple molecules to peptides, while ensuring exceptional homogeneity and thermodynamic stability. Advantageously, the solvents obtained do not exhibit phase change, i.e., no recrystallization, between -25°C and +45°C for a period of at least 6 months.

[0168] Example 3: Solubilization of hydrophilic and hydrophobic active ingredients and plant extract(s) taken alone in different solvents

[0169] Tests were carried out to determine the solubility limit of vitamin C, rucinol, niacinamide, ferulic acid, retinol, tocopherol, copper peptide and an extract of Centella asiatica, taken alone, in different solvents, as well as in water for comparison.

[0170] Vitamin C, niacinamide, and copper peptide are water-soluble active ingredients. Rucinol, ferulic acid, tocopherol, and retinol are fat-soluble active ingredients. The Centella asiatica extract used refers to a plant extract (cosmetically and / or pharmaceutically active) comprising a variety of water-soluble and fat-soluble molecules. Therefore, Centella asiatica extract should be considered an active ingredient that is both water-soluble and fat-soluble.

[0171] Solubility measurements were performed after saturation of the solvent with the active ingredient in question, followed by analysis by high-performance liquid chromatography (HPLC), or by visual determination.

[0172] Solubility determinations were conducted according to a standardized experimental protocol.

[0173] In the case of active ingredients taken alone, 0.4 g of solvent were introduced into a microcentrifuge tube with 0.2 g of active ingredient.

[0174] The samples were subjected to vortex shaking (OHAUS, model VXMNDG) at 1000 rpm for a period of 15 hours.

[0175] At the end of this step, the microtubes were centrifuged (ONILAB, model CF0506) at 4000 rpm for 15 minutes in order to separate the supernatant from the undissolved solid.

[0176] A volume of 33 pL of supernatant was then taken and diluted to 10 mL in phosphate buffer (50 mM, pH 3.3) for vitamin C, water for niacinamide or acetonitrile for rucinol.

[0177] An aliquot of 50 pL of this diluted solution was then mixed with 10 pL of an internal standard solution consisting of pyridoxine at a concentration of 5 g / L in water, and then made up with 440 pL of solvent, namely phosphate buffer for vitamin C, water for niacinamide or an acetonitrile / water mixture (7:3, v / v) for rucinol.

[0178] The solutions thus obtained were analyzed by HPLC.

[0179] Tocopherol, retinol, copper peptide, ferulic acid, and Centella asiatica extract were analyzed by visual characterization. When no residual solids were observed after centrifugation, this indicated that saturation had not been reached. In this case, an additional 0.2 g of the active ingredient was added, and the agitation process was repeated, with this addition potentially repeated up to two times. Beyond this point, the solubility of the active ingredient was considered to exceed 60% by mass, a value significantly higher than the concentrations typically used in cosmetic formulations.

[0180] The state of solubilization was assessed visually by observing the presence or absence of residual solids. If such residues were present, the quantity of each active ingredient actually solubilized was determined by HPLC analysis or by visual inspection.

[0181] Chromatographic analyses were performed using a Shimadzu HPLC system equipped with a diode array detector (DAD).

[0182] The separation of the compounds was carried out on a Macherey-Nagel Nucleosil 100-5 C18 AB column (5 µm, 250 × 4.6 mm), maintained at a temperature of 25°C.

[0183] The mobile phase, delivered at a flow rate of 0.5 mL / min, comprised three solvents, namely a phosphate buffer (50 mM, pH 3.3), acetonitrile and water containing 1% by volume of acetic acid.

[0184] The elution conditions were adapted to each active ingredient, with a mobile phase consisting of 95% phosphate buffer and 5% acetonitrile for vitamin C and niacinamide, and 70% acetonitrile and 30% acidified water for rucinol.

[0185] The analysis time was 10 minutes.

[0186] Quantification was performed by internal calibration using calibration lines established for each active ingredient from standard solutions with concentrations between 0.01 and 0.2 g / L and containing 0.1 g / L of pyridoxine as an internal standard.

[0187] For the preparation of the internal standard solution, the volumetric flask was first tared, and then approximately 50 mg of pyridoxine was accurately weighed, with the exact mass recorded. Water was then added to completely dissolve the compound, with the volume adjusted as needed. The solution was made up to the calibration mark with water and then homogenized directly in the flask. The actual pyridoxine concentration was determined based on the added mass and the final volume, and then divided by a dilution factor of 50. The resulting value was used as the reference for each sample in the HPLC sequence.

[0188] For the solubilization experiments, the solvents used are presented in Table 5 below. Table 5:

[0189] Viscosity Percentage

[0190] LogP LogP Ratio Density at 25°C Name Compound 1 Compound 2 mass

[0191] 1.2 molar (g / mL) and 1000 of water

[0192] (mPa.s) 5% (Water

[0193] G2B1-R- added during

[0194] Glycerol -1.8 Betaine -2.39 2:1 1.20 573.6 W5 of the

[0195] synthesis)

[0196] 30% (Added)

[0197] G2B1-O- Glycerol -1.8 Betaine -2.39 2:1 after 1.14 5.1 W50

[0198] synthesis)

[0199] 1,3- P6C1 -1 Citric acid -1.7 6:1 0% 1.16 218.8 Propanediol

[0200] 30% (Added)

[0201] P6C1-O- 1,3- -1 Citric acid -1,7 6:1 after the 1,15 16,2 W30 Propanediol

[0202] synthesis)

[0203] 1,3- P6S1 -1 Succinic acid -0.6 6:1 0% 1.11 60.1 Propanediol

[0204] Acid

[0205] 1,3- Succinic Acid

[0206] P12S1T1 -1 -0.6 6:1 0% 1.12 84.7 Tartaric propanediol (ratio 1:

[0207] 1)

[0208]

[0209] G4L1 Glycerol -1.8 Lactic acid -0.7 4:1 0% 1.25 463.6 Polar solvents are solvents formed from two compounds with negative logP (G2B1, P6C1, P12S1T1 and G4L1).

[0210] The solubility results of the different active ingredients (taken alone) are presented in Table 6 below.

[0211] Table 6:

[0212] Solubility (% by mass)

[0213] Peptide Extract Vitamin Acid

[0214] Niacinamide, Rucinol, Retinol, Tocopherol, and C-ferulic solvent

[0215] copper Centella 28.4 ± 1.5 ±

[0216] Eau 38,8 ± 0,4% î _* 0% t 0% t 4,53% f >2% f 0,2% î 0,0% î

[0217] G2B1-R- 22,1 ± 1,3 ±

[0218] 10,8 ± 0,5% î _* _* _* _* >2% f W5 0,7% î 0,1% î

[0219] G2B1-O- 30,7 ± 0,3-0, 5%

[0220] 23,3 ± 0,6% î > 60% f _* _* _* >2% f W50 0,5% î t

[0221] 6,7 ± > 4,93% P6C1 21,6 ± 0,2% î > 60% f > 2% | 0% t 0% t < 1,5% f 0,1% î t P6C1-O- 15,1 ± > 60% f

[0222] 31,9 ± 0,3% î 1 -2% f _* _* _* >2% f W30 0,4% î î

[0223] 7,29-9,7% 13,42-18,8% > 4,76% > 0,5% > 8,66% P6S1 _* 0% t _* t t t t t 5,15- 13,79-20,9% > 4,76% 0,11 - P12S1T1 _* 0% t 0% t _*

[0224]

[0225] 9,88% f t t 0,4% f8,3 ± 56,2 ±

[0226] G4L1 20,3 ± 0,1% J _* _* _* _* 1,5-2% f

[0227]

[0228] 0,4% J 0,6% J

[0229] The symbol f indicates that the value is determined visually, the symbol J indicates that the value is determined by HPLC, and the symbol * indicates that no data has been measured.

[0230] The results obtained highlight that solvents, whether aqueous or anhydrous, particularly those based on monocarboxylic acids (G4L1), polycarboxylic acids (P6C1) or amino acid derivatives (G2B1-R-W5 and G2B1-O-W50), have a remarkable ability to simultaneously solubilize hydrophilic compounds, such as niacinamide and vitamin C, as well as hydrophobic compounds, such as rucinol.

[0231] This ability to solubilize active ingredients of different polarities constitutes a significant advantage for the formulation of compositions comprising multiple active ingredients.

[0232] When saturation is not reached for concentrations above 60% by mass, solubility is considered to exceed this value, based on visual observation of the absence of residual solid phase.

[0233] In the particular case of rucinol in the solvent P6C1-O-W30, an HPLC analysis was nevertheless carried out in the absence of apparent saturation, allowing a concentration of 62.9 ± 3.6% to be determined, consistent with the quantity of active ingredient initially introduced, thus confirming a very high solubility.

[0234] With regard to polar solvents (G2B1-R-W5, G2B1-O-W50, P6C1 and G4L1), it has been observed that, in the absence of water or in the presence of small proportions of water, the solubility of hydrophilic actives may be lower than that observed in water alone, while remaining significant.

[0235] Introducing water in a higher proportion (i.e., up to 50%) into these systems leads to a notable increase in the solubility of these same hydrophilic actives, which can be explained by a better polarity match between the solvent medium and the compounds considered.

[0236] Conversely, rucinol generally exhibits high solubility in polar solvents, whether aqueous or anhydrous, with the exception of certain specific systems in which structuring phenomena or high viscosity can disrupt phase separation and lead to an experimental underestimation of solubility.

[0237] Further tests carried out with other active ingredients confirm the versatility of solvents.

[0238] Furthermore, it should be noted that tocopherol, which falls outside the scope of the invention because its Hansen parameters differ from the ranges of interest, exhibits significantly lower (or even zero) solubility in solvents compared to the other tested active ingredients. This observation is consistent with the scope of the invention as defined, given that only the active ingredients with Hansen parameters of 6D between 17 and 22 MPa Q0.5, 6P between 2 and 18 MPa Q0.5, and 6H between 4 and 42 MPa Q0.5, are properly solubilized.

[0239] These results confirm the value of solvents as adaptable solubilization media, suitable for a wide range of active ingredients with varied physicochemical properties.

[0240] Example 4: Solubilization of hydrophilic and hydrophobic active ingredients combined in different solvents

[0241] In the case of solubilization of active ingredients in combination, 20 mg of each of the active ingredients (i.e.

[0242] 2% of each active ingredient) were introduced into a microtube containing 0.94 g of solvent.

[0243] The active ingredients tested are vitamin C, niacinamide and rucinol.

[0244] The mixture was vortexed and then centrifuged under the conditions described in Example 3.

[0245] The solubilization of each active ingredient in the different combinations is then evaluated by HPLC, or by visual determination.

[0246] The results are presented in Table 7 below.

[0247] Table 7:

[0248] Solubility in combination (% by mass)

[0249] Niacinamide (logP=- Solvent Vitamin C (logP=-2.15) Rucinol (LogP=2.4) 0.37)

[0250] G2B1-O-W50 > 2% † > 2% † > 2% † P6C1 1.94% ‡ 1.11% ‡ 1.09% ‡ P6C1-O-W30 1.57% ‡ 1.39% ‡ 1.13% ‡

[0251]

[0252] G4L1 0.89% ‡ 1.38% ‡ 1.05% ‡

[0253] The symbol † indicates that the value is determined visually and the symbol ‡ indicates that the value is determined by HPLC.

[0254] The results show that the presence of multiple active ingredients influences the solubility of each active ingredient.

[0255] We observe that all the solvents tested are capable of solubilizing a significant amount of each active ingredient, lipophilic and hydrophilic, taken in combination.

[0256] In particular, the G2B1-O-W50 solvent allows the 3 active ingredients to be solubilized in their entirety.

Claims

DEMANDS 1. Cosmetic and / or pharmaceutical composition comprising a solvent containing a mixture of: at least one polyol, taken alone or in combination, having a Hansen parameter 6H between 18 and 30 MPa^0.5, and at least one carboxylic acid, taken alone or in combination, in which the ratio between the number of hydroxyl group(s) -CH2OH (primary alcohol) in the mixture and the number of carboxylic acid group(s) -COOH in the mixture is between 3 -CH2OH for 1 -COOH and 8 -CH2OH for 1 -COOH, and ■ The average molecular mass of said mixture is less than 130 g·mol -1 , and at least one cosmetically and / or pharmaceutically active compound exhibiting Hansen parameters respectively 6D between 17 and 22 MPa^0.5, 6P between 2 and 18 MPa^0.5 and 6H between 4 and 42 MPa^0.5, characterized in that the composition comprises a combination of at least one fat-soluble active ingredient and at least one water-soluble active ingredient.

2. Composition according to claim 1, characterized in that the polyol is selected from 1,3-propanediol, 1,2-propanediol, 1,5-pentanediol, glycerol, sorbitol, erythritol, pentaerythritol, threitol, galactitol, preferably from 1,3-propanediol, 1,5-pentanediol, glycerol, more preferably from 1,3-propanediol.

3. Composition according to claim 1 or 2, characterized in that the carboxylic acid is selected from succinic acid, citric acid, tartaric acid, malic acid, lactic acid, adipic acid, itaconic acid, 2,5-furandicarboxylic acid, citramalic acid, glutaric acid, D-mannonic acid, 3-hydroxybutyric acid, trihydroxyglutaric acid, galacturonic acid, 3-hydroxypropionic acid, 2-hydroxyglutaric acid, fumaric acid, D-malic acid, oxalic acid, betaine, preferably succinic acid, citric acid, tartaric acid, oxalic acid, betaine, lactic acid, more preferably citric acid, or succinic acid taken alone or in combination with tartaric acid.

4. Composition according to any one of the preceding claims, characterized in that the ratio between the number of hydroxyl group(s) -CH2OH (primary alcohol) and the number of carboxylic acid group(s) -COOH of the mixture is between 4 -CH2OH for 1 -COOH and 6 -CH2OH for 1 -COOH.

5. Composition according to any one of the preceding claims, characterized in that the average molecular mass of said mixture is between 100 and 120 g·mol -1 .

6. Composition according to any one of the preceding claims, characterized in that the fat-soluble active ingredient is selected from retinoids such as retinol, rucinol, quercetin, resveratrol, menthol, ferulic acid, palmitoyl tripeptide, and a plant extract comprising polar and nonpolar molecules such as an extract of Centella asiatica, taken alone or in combination.

7. Composition according to any one of the preceding claims, characterized in that the water-soluble active ingredient is selected from ascorbic acid, niacinamide, caffeine, copper peptide (GHK-Cu), and a plant extract comprising polar and nonpolar molecules such as an extract of Centella asiatica, taken alone or in combination.

8. Composition according to any one of the preceding claims, characterized in that it has a viscosity between 1 mPa.s and 8000 mPa.s.

9. Composition according to any one of the preceding claims, characterized in that it is in a form suitable for topical or oral application.

10. Composition according to claim 9, characterized in that it is in a form selected from serums, gels, lotions, mists or biphasics.

11. Use of a composition according to any one of claims 1 to 10, wherein the active compound is a cosmetically active compound for the care of the skin and hair, for improving well-being or personal or oral hygiene.

12. Composition according to any one of claims 1 to 10, wherein the active compound is a pharmaceutically active compound for its use as a medicinal product.

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