MICROCAPSULES; PROCESS FOR PREPARING MICROCAPSULES CONTAINING A BIOLOGICALLY ACTIVE COMPOUND AND LIQUID SOLUTION

Abstract: This invention refers to microcapsules containing biologically active compounds, destined to make available said active compounds inside an individual, such as in certain skin layers, digestive tract or blood circulation, being described the association of such biologically active compounds to a liquid solution capable of reducing its flow from said microcapsule. The invention also discloses a process for the preparation of microcapsules containing a biologically active compound and a liquid solution having a viscous flow of a pre-established degree.

Description: Title: "Microcapsules; Process for Preparing Microcapsules Containing a Biologically Active Compound and Liquid Solution". Field of the Invention: This invention refers to microcapsules containing biologically active compounds, destined to make available said active compounds inside an individual, such as in certain skin layers, digestive tract or blood circulation. The invention also discloses a process for the preparation of microcapsules containing a biologically active compound and a liquid solution having a viscous flow of a pre-established degree. Of the prior art: As it is well known in the art, microcapsules are capsules of microscopical size, adapted for containing and dispensing, in an advantageous manner, a biologically active compound, such as a cosmetic, pharmaceutical or nutritional compound, to be ad- ministered to an individual in need of such ingredients to prevent or solve some organic problem. Said microcapsules are discussed, for instance, in US Patent 5.395.620 (Hue et al) the disclosures of which are hereby incorporated by reference. Said microcapsules, preferably made of organic material, have the function of conveying and dispensing the biologically active compound contained within them, to a certain site or region of the individual, preserving and maintaining the proprieties of said compound. Said microcapsules are particularly adapted for the administration of vitamins to individuals. When referring to C vitamin used topically with the purpose of stimulating the synthesis of collagen for the correction of skin imperfections as wrinkles and others, it is desirable that the biologically active compound, C vitamin in this case, be released below the corneous layer of the skin. Thus, microcapsules made of organic materials are particu- larly useful for this type of application, since they are compatible with the live beings organisms, and are easily degradable without impairing individual or environment. However, a common problem to all microcapsules is the difficulty of keeping the biologically active compounds in their interior, since the latter are usually made of materials that permeate the reticules of the microcapsules, and are released before reaching the selected site in the individual. So far, the problem of keeping the biologically active compounds within the microcapsules has been mainly solved by the modification of the structure, and specially of the walls of the microcapsule, with the purpose of rendering it impermeable to its contents, and particularly to the biologically active compound. In spite of such approach actually solving the problem of the undesired outflow of the biologically active compound, it also presents, among others, the inconvenience of causing the loss of part of the biophysical-chemical properties of the capsules, due to the changes in its structure. Examples of this and other approaches, including the use of liposome capsules, the disadvantage of which is the difficult selection of ingredients for their composition, are disclosed in Patents JP 8325117, US 5.069.936, JP 2293041 , JP 2164439, EP 0 207 655, DE 2706705, BE 873865, US 5.160.529, US 5.332.584, US 4.789.516, US 4.532.123, US 5.656.469 e US 5.453.368, among others. Considering that such containers may present a similar degree of reticulation, another disadvantage of modifying the microcapsules is the need to develop a specific and compatible container for each biologically active compound to be used, thus rendering the process of manufacturing microcapsules containing biologically active compounds a very expensive one. Scope of the invention The major purpose of this invention is to minimize the undesired outflow of a biologically active compound from a microcapsule, without modifying the structure of the latter, so that the ability of releasing the contents of the microcapsule may occur in a retarded manner, or even a programmed one. Which is to say, so that the release of the biologically active compounds is initiated as of a certain moment, in a certain region of the indi- vidual, after its introduction in the organism of the individual. ln this sense, and contrary to prior techniques, this invention has as its premise the modification of the properties of the biologically active compound itself, so that it will present a reduced ability to outflow, keeping unaltered the microcapsule that contains it. Thus, a first aspect of the invention foresees the association of the biologically active compound to a liquid solution capable of reducing its outflow. In a preferential embodiment, it is foreseen the association of the biologically active compound to be contained in the microcapsule to a solution of viscous flow. Such an association may occur through a substantial dissolution of said compound in the liquid solution, prior to its intro- duction in the container. Viscous flow, unless otherwise specified, is hereby defined as any flow of a liquid where viscosity is different from zero. Therefore, any biologically active compound associated to a solution with a viscous flow lies within the scope of the invention. In view of the above considerations, the purpose of this invention is reached by means of a microcapsule characterized by the fact of being the carrier of a biologically active compound associated to a liquid solution capable of reducing the outflow of said compound from said container. One other aspect of this invention refers to a process for preparing microcapsules containing a biologically active compound, characterized by the fact of comprising a step of associating said compound to a liquid solution capable of reducing the outflow of said compound from said container. This invention refers yet to a liquid solution containing a biologically active compound, adapted to be inserted into a microcapsule, and characterized by the fact of presenting a viscous flow of a predetermined level. Detailed Description of the Invention: As already mentioned above, the basic premise of this invention is the association of a biologically active compound to be contained in a microcapsule, to a liquid solution capable of reducing the outflow of said biologically active compound from its microcapsule. According to a preferable embodiment which is solely given as an example, said liquid solution presents a viscous flow of a predetermined degree, to prevent the outflowing of the compound through the reticules of the container at an undesired occasion, such as, for instance, before reaching a certain region within the individual who received it. The solution, in which said compound was dissolved before its introduction in the container, may be alcohol or aqueous, depending in the solubility of the biologically active compound, and shall contain at least one polymer dissolved therein, such as poly- vynilalcohol or polyvynilthioalcohol and their combinations. Studies performed by the Applicant have shown that the degree of viscosity of said liquid solution can be advantageously determined by the variation of the concentration of said polymer in a substantially reverse ratio to its molecular weight. Since the aqueous solution given hereby as an example should present a viscosity greater than about 4 mPa.s., and preferably greater than about 8 mPa.s., the molecular weight of said polymers may be in the range of 70,000 g/mol to 200,000 g/mol, while the concentration of said polymers may be of about 1 % w/v to about 5% w/v, with a greater preference for about 1 % w/v. The organic microcapsules are advantageously prepared from a matrix containing selected molecules from the group comprising protein molecules, glycosaminegiicanes molecules, polysaccharides molecules, and the combinations thereof. The protein and glycosaminegiicanes molecules may be derived from the sea, or from terrestrial mammals, wnile tne molecules of the useful polysaccharides are of vegetable origin. In a preferred way, the protein molecules are collagen molecules, and the glycosaminegiicanes molecules are chondroitin sulfate molecules. The polysaccharide molecules are, preferably, galactomannose molecules. The preferred organic microcapsules have a substantially globular shape, and present a statistical distribution of size smaller than 100 micra, and , more preferably, between 3 and 60 micra. The biologically active compound to be introduced in the organic containers is selected among cosmetic, pharmaceutical or nutritional compounds, such as for instance the various compounds identified as C Vitamin, which include but are not limited to, levoro- tatory ascorbic acid, its salts, esters, derivations and combinations. One must bear in mind that the above description refers only to one exempli- ficating embodiment of this invention, the scope of which is defined in the following Claims:

Claims: Claims 1- A microcapsule characterized by the fact of being the carrier of a biologically active compound associated to a liquid solution capable of reducing the outflow of said compound from said microcapsule. 2- A microcapsule according to Claim 1 , characterized by the fact of said liquid solution presents a viscous flow. 3- A microcapsule according to Claims 1 or 2, characterized by the fact of said liquid solution being aqueous and containing at least one polymer 4- A microcapsule according to Claim 3, characterized by the fact of said polymer being substantially dissolved in said liquid solution. 5- A microcapsule according to Claims 3 or 4, characterized by the fact of the viscosity of said liquid solution being determined by the variation of the concentration of said polymer in a substantially reverse ratio to its molecular weight. 6- A microcapsule according to any of the preceding Claims, characterized by the fact of said microcapsule being made of organic material. 7- A microcapsule according to Claim 6, characterized by the fact of the material of said microcapsule being selected from groups of molecules derived from the sea, or from terrestrial mammals, or of vegetable origin, and combinations thereof. 8- A microcapsule according to Claim 7, characterized by the fact of the material of said microcapsule being selected from glycoseamineglicanes, proteins, polysaccharides and combinations thereof. 9- A microcapsule according to any of the Claims 6 to 8, characterized by the fact of the material of said microcapsule being selected from collagen, atelocollagen, poly- holosides, chondroitin sulfate, their byproducts and their combinations. 10- A microcapsule according to any of the Claims 1 to 9, characterized by the fact of the biologically active compound being selected from cosmetic, pharmaceutical or nutritional compounds. 11- A microcapsule according to Claim 10, characterized by the fact of the biologically active compound being a vitamin. 12- A microcapsule according to Claim 1 1 , characterized by the fact of the vitamin being selected from levorotatory ascorbic acid, its salts, esters, derivatives and combinations thereof. 13- A microcapsule according to Claim 12, characterized by the fact of the polymer contained in the liquid solution being selected from polyvynilalcohol or poly- vynilthioalcohol and their combinations. 14- A microcapsule according to Claim 13, characterized by the fact of the liquid solution presents a viscosity greater than about 4 mPa.s. 15- A microcapsule according to Claim 14, characterized by the fact of the liquid solution presents a viscosity greater than about 8 mPa.s. 16- A process for the production of microcapsules containing a biologically active compound, characterized by the fact it comprises a step of association of said compound to a liquid solution capable of reducing its outflow from said microcapsule. 17- A process according to Claim 16, characterized by the fact of said asso- ciation occurring by means of a substantial dissolution of said compound in the liquid solution prior to its introduction in the container. 18- A process according to Claim 17, characterized by the fact of said liquid solution presents a viscous flow of a predetermined degree. 19- A process according to Claim 18, characterized by the fact of said liquid solution being aqueous and containing at least one polymer substantially dissolved therein. 20- A process according to Claim 19, characterized by the fact of the viscosity of said liquid solution being determined by the variation of the concentration of said polymer in a substantially reverse ratio to the molecular weight of said polymer. 21- A process according to Claim 20, characterized by the fact of said microcapsule being made of organic material, comprising molecules selected from a group formed by protein, glycoamineglicane and polysaccharide molecules, and combinations thereof. 22- A process according to Claim 21 , characterized by the fact of said protein molecules being collagen molecules, the glycoamineglicane molecules being chondroitin sulfate molecules, and the polysaccharide molecules being galactomannose molecules. 23- A process according to any of the Claims 15 to 22, characterized by the fact of the biologically active compound being selected from levorotatory ascorbic acid, its salts, esters, derivatives and combinations thereof. 24- A process according to any of the Claims 18 to 23, characterized by the fact of said polymer being selected from polyvynilalcohol or polyvynilthioalcohol and their combinations. 25- A process according to any of the Claims 17 to 24, characterized by the fact of said liquid solution presents a viscosity greater than about 4 mPa.s. 26- A process according to Claim 25, characterized by the fact of said liquid solution presents a viscosity greater than about 8 mPa.s. 27- A liquid solution containing a biologically active compound, adapted to be introduced in a microcapsule characterized by the fact of presents a viscous flow of a pre- determined degree. 28- A liquid solution according to Claim 27, characterized by the fact of being aqueous, containing at least one polymer substantially dissolved therein, and its viscosity being determined by the variation of the concentration of said polymer in a substantially reverse ratio to the molecular weight of said polymer. 29- A liquid solution according to Claims 27 and 28, characterized by the fact of said compound being substantially dissolved in the liquid solution prior to its introduction in the microcapsules, and by said microcapsules being formed of organic material, comprising molecules selected from a group which comprises protein, glycoamineglicane and polysaccharide molecules, and combinations thereof. 30- A liquid solution according to Claim 29, characterized by the fact of said protein molecules being collagen molecules, the glycoamineglicane molecules being chon- droitin sulfate molecules, and the polysaccharide molecules being galactomannose molecules. 31- A liquid solution according to Claims 27 to 29, characterized by the fact of said biologically active compound being selected from levorotatory ascorbic acid, its salts, esters, derivatives and combinations thereof. 32- A liquid solution according to Claims 28 to 31 , characterized by the fact of said polymer being selected from polyvynilalcohol or polyvynilthioalcohol and their combina- tions. 33- A liquid solution according to any of the Claims 27 to 32, characterized by the fact of said liquid solution presenting a viscosity greater than about 4 mPa.s. 34- A liquid solution according to Claim 33, characterized by the fact of said liquid solution presents a viscosity greater than about 8 mPa.s.

Inventors: ALCANTARA MARTINS ZUCCHETTI RO, POMMEZ PHILIPPE JOSEPH, ALCANTARA MARTINS ZUCCHETTI, ROBERTO, POMMEZ, PHILIPPE, JOSEPH
Applicants: ALCANTARA MARTINS ZUCCHETTI RO, COSMETICOS NATURAL IND COM, POMMEZ PHILIPPE JOSEPH, ALCANTARA MARTINS ZUCCHETTI, ROBERTO, INDUSTRIA E COMERCIO DE COSMETICOS NATURA LTDA., POMMEZ, PHILIPPE, JOSEPH
Application year: 1998
Main classification: A61K9
IPC codes: A61K9, A61K47