Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K9/00—Medicinal preparations characterised by special physical form
  • A61K9/48—Preparations in capsules, e.g. of gelatin, of chocolate
  • A61K9/50—Microcapsules having a gas, liquid or semi-solid filling; Solid microparticles or pellets surrounded by a distinct coating layer, e.g. coated microspheres, coated drug crystals
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
  • A61K47/30—Macromolecular organic or inorganic compounds, e.g. inorganic polyphosphates
  • A61K47/36—Polysaccharides; Derivatives thereof, e.g. gums, starch, alginate, dextrin, hyaluronic acid, chitosan, inulin, agar or pectin
• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23L—FOODS, FOODSTUFFS OR NON-ALCOHOLIC BEVERAGES, NOT OTHERWISE PROVIDED FOR; PREPARATION OR TREATMENT THEREOF
  • A23L27/00—Spices; Flavouring agents or condiments; Artificial sweetening agents; Table salts; Dietetic salt substitutes; Preparation or treatment thereof
  • A23L27/70—Fixation, conservation, or encapsulation of flavouring agents
  • A23L27/72—Encapsulation
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K9/00—Medicinal preparations characterised by special physical form
  • A61K9/14—Particulate form, e.g. powders, Processes for size reducing of pure drugs or the resulting products, Pure drug nanoparticles
  • A61K9/16—Agglomerates; Granulates; Microbeadlets ; Microspheres; Pellets; Solid products obtained by spray drying, spray freeze drying, spray congealing,(multiple) emulsion solvent evaporation or extraction
  • A61K9/1605—Excipients; Inactive ingredients
  • A61K9/1629—Organic macromolecular compounds
  • A61K9/1652—Polysaccharides, e.g. alginate, cellulose derivatives; Cyclodextrin

Definitions

• the present invention is concerned with a method for encapsulating or for coating one or more active substances in one or with a carrier substance, with an encapsulated or coated active substance which is encased by means of a carrier substance, and with applications of the invention Method.
• active ingredients e.g. pharmaceuticals, adhesives, fragrances, detergent additives, dyes, concrete additives, pesticides, etc.
• active ingredients e.g. pharmaceuticals, adhesives, fragrances, detergent additives, dyes, concrete additives, pesticides, etc.
• active ingredients must be protected from environmental influences, such as moisture, UV radiation, mechanical stress, etc., and at the same time they should be easy to dose and practical to use.
• EP-A-0 092 908, EP-PS-0 090 600, EP-A-0 118 240 and EP-A-0 304 401 describe the production of capsules by means of injection molding or deep-drawing, whereby for Production of the capsules hydrophilic polymers, such as gelatin or starch, are proposed, which are at least partially brought into thermoplastically processable form for the processing and the production of the capsules by means of suitable processes. It is exclusively here for the production of capsules of a larger type, which are filled or filled with active substances only after their production. be closed.
• An active ingredient such as e.g. an active agent, a core material, a filler, a nucleide, etc., encapsulated by a support material, a coating, a membrane, etc.
• the size of these microcapsules is between 1 and 1000 ⁇ m. The most important areas of application are in the manufacture of carbon-free copy papers and in the microencapsulation of active pharmaceutical ingredients.
• microcapsules per se are sufficiently described in the two literature citations mentioned and the various manufacturing processes are varied and extensive, a detailed description thereof is dispensed with, so that the content of these two literature citations is hereby fully included in the present description. Introduction to the letter is to be considered.
• Microcapsules ha ⁇ ben the major drawback that they are very expensive and thus materials only in connection with expensive Wirk ⁇ , th as' for example, pharmaceutical Produk ⁇ are even debatable.
• This statement is further corroborated in the literature section by Kirk-Othmer on p. 491 in the last section by stating here that so-called "large scale" industrial use of the production of microcapsules is limited due to high costs and thus only in pharmaceuticals ⁇ rich who has medicine and some special markets prospects for the future.
• the carrier substance used for the encapsulation or coating preferably comprising a material, that when reusing the active substance resp. of the active ingredient can also be used, so that neither waste products arise nor the further use of the active substance is negatively influenced by the carrier substance.
• a method of encapsulation is proposed or for coating one or more active substances in or with a carrier substance, by using a mixture of essentially native starch and at least one agent which at least partially swells the starch and which is used for the encapsulation or for the encapsulating or coating carrier substance Coating is mixed together with the active ingredient and at least one emulsifier.
• the swelling agent comprises at least one substance as described in the characterizing part of one of claims 2 to 5 or 9.
• starch swelling or swelling agent is preferably chosen such that the active substance to be encapsulated is weakly or hardly soluble in the swelling agent.
• the at least partially swollen starch contains less than 12% by weight of water when the active substance is encapsulated or coated, which in a further preferred embodiment of the process according to the invention can result in the swollen starch being largely free of water.
• the active ingredient itself is at least partially the starch-swelling agent or is soluble in the swelling agent.
• Solvents of starch have in particular been found to be glycerol and amino alcohols, as claimed in the characterizing part of claim 5.
• the amino alcohols can be monomers as well as oligomers of the amino alcohols mentioned.
• Triaethanolamine for example, has proven particularly suitable.
• an emulsifier is further added to the mixture of native starch and the swelling agent. Due to the interfacial activity, this emulsifier accumulates on the surface of the swollen starch and influences the wetting between the active ingredient and the swollen starch. The complete wetting of the swollen starch is supported by the emulsifier, whereby the absorption of the active substance by the starch or. the coating of the active substance is favored. It is preferably proposed to use up to about 4% by weight, based on the total mixture of the emulsifier.
• the swelling agent-starch phase does not form a coherent, homogeneous mass
• at least one oil-like substance is added when the swollen starch is mixed with the active substance. which essentially cannot form a homogeneous mixture with the starch, respectively.
• the oil and the swollen starch form two separate phases and the swollen starch granules are coated with an oil film or are dispersed in the oil.
• the active ingredient when the swollen starch is mixed with the active ingredient, up to 10% by weight, preferably 5 to 10% by weight, based on the total mixture, of an oil-like substance which cannot be mixed homogeneously with the swollen starch. It is essential that the active ingredient is not soluble in this oily phase, on the one hand, and, moreover, it must be better wettable by the swelling agent-starch phase than by the oil phase, which ensures that the starch-swelling agent phase envelops the active ingredient.
• the native starch is at least partially swollen and mixed with the swelling agent in such a way that essentially a grain structure is retained.
• the temperature is not chosen so high that the grains are melted and form a homogeneous amorphous starch phase.
• the mechanical stress on the grains may only be so great that the active ingredient is incorporated into the grains, but the grains are not destroyed.
• the structural viscosity of the starch grains must not fall below a lower limit, which is approximately
• the swollen starch granules can already have an increased amorphous structure, but the individual granules are not yet coagulating, ie there is still no homogeneous melt. The so-called particulate phase of the swollen starch must be retained.
• the temperature when mixing the individual components when using 40% glycerol as a swelling agent must not exceed 170 ° C.
• the swelling agent up to 60% by weight, preferably 30 to 50% by weight, of the swelling agent is added.
• the choice of the amount of swelling agent to be added depends heavily on the swelling agent chosen, so that, of course, effective substances can also be effectively encapsulated with less than 30% of swelling agent added, such as water.
• the grains become too soft, so that they break apart even with a small mechanical load and the granular, powdery material can stick together to form a compact mass.
• the swelling agent after encapsulation resp. to remove the coating at least partially.
• the amount of emulsifier used is preferably 1 to 2% by weight, based on the mixture as a whole.
• the method according to the invention for encapsulating or for coating one or more active substances in or with a carrier substance comprises, in particular, mixing a mixture of 20 to 60% by weight of a swelling agent for the swelling of the native starch, preferably 30 to 50% by weight 0.1 to 4% by weight of an emulsifier, from 0 to 10% by weight of an oily substance, and the remainder of native starch in a mixing unit, such as a mixer, kneader or extruder, the mixing taking place together with the active ingredient, preferably at an elevated temperature to produce an essentially homogeneous powder, which encapsulated or. contains coated active ingredient.
• a mixing unit such as a mixer, kneader or extruder
• the mechanical agitation in the mixer, kneader or extruder at elevated temperature takes place because the wetting and sorption process of the swollen starch by the active substance takes place very slowly without these additional measures due to the high viscosity of the starch / swelling agent phase.
• the swelling process can also be carried out at room temperature, with the following problems:
• the mixture is first heated to a temperature which is below the melting temperature of the starch / swelling agent mixture.
• the starch is then at least partially swollen by means of the swelling agent, whereupon the swollen starch envelops or seals the active substance under the action of the mechanical mixing agitation. absorbs this by sorption, the emulsifier and optionally the oil causing an essentially homogeneous powder to be formed instead of a coherent mass.
• emulsifiers i.a.
• the following substances have been shown to be suitable:
• a polyoxyethylene derivative of a sorbitan ester such as, for example, Tween from ICI
• Triglyce- rid used '.
• the dosage of the carrier substance with the active substance or substances takes place through the choice of the average grain size of the native starch used and / or the degree of swelling of the starch, respectively. the ratio of some starch to swell. If, for example, a native starch grain of maize is assumed, the mean grain size of which is in the range of approx. 14 ⁇ m, such a starch grain can be "filled" with an active substance much more weakly than, for example, a native starch grain of the potato, whose mean grain size is in the range of is about 35 ⁇ m. In general it can be stated that the larger the mean grain size of the native starch from which it is based, the more active substance can be coated with the same protective effect. However, it should be borne in mind that larger grains probably have a greater protective effect, but the overall mixture of the encapsulated active substances is less homogeneous.
• an encapsulated or coated active ingredient is produced, which is encased by means of a carrier substance, the carrier substance for the encapsulation or.
• Coating consists essentially of at least partially swollen starch.
• the encapsulated or coated active ingredient is characterized in particular by the fact that a mixture of essentially native substances is used to produce it as an encapsulating or coating carrier substance Starch and at least one agent which at least partially swells the starch is used, which is mixed for the encapsulation or for the coating together with the active ingredient and at least one emulsifier.
• the methods according to the invention described above are particularly suitable for encapsulating or coating active pharmaceutical ingredients and / or for the production of medicaments or medical indications.
• the method according to the invention is also particularly interesting for encapsulating water-soluble or water-miscible substances, in particular water-soluble vitamins and citric acid.
• the processes are also suitable for the encapsulation or coating of adhesives, flavorings, fragrances, detergents, pesticides, herbicides, colorants, synthetic resin additives, building material additives, concrete additives and / or reactants for the coating of carbon-free copy papers.
• Heating zone 1 113 ° C,
• Heating zone 2 116 ° C
• Heating zone 3 122 ° C,
• the product was a fluffy, white powder, whereby under the microscope you can clearly see individual grains that are swollen with glycerin.
• An average particle size of approx. 100 ⁇ m is achieved by homogenization in the kneader.
• the oil used prevents the starch polymer balls from sticking together.
• Other starches can of course also be used as the polymer, which in the present example is potato starch.
• 20% vitamin C was added to the powder obtained in the above manner and kneaded in with the same parameters. The result is also clearly visible under the microscope. Most of the vitamin C crystals are embedded in the elastic bodies. If, for example, the grains are pressed flat, the embedded vitamin C crystals can be seen under the polarizing microscope.
• the method is also suitable for encapsulating other vitamins, pharmaceutical or cosmetic active ingredients, the encapsulation or coating of. with water-soluble or with water-miscible substances, such as in particular water-soluble vitamins and others. with citric acid.
• water-soluble or with water-miscible substances such as in particular water-soluble vitamins and others. with citric acid.
• some active substances were processed in accordance with the method according to the invention in the following example 6, the list of possible active substances naturally being expandable in a wide variety of ways.
• thermoplastically processable starch containing approx. 27% to 30% glycerol, incorporated.
• the practical implementation was carried out at 140 ° C. in a so-called Brabender kneader, 70g batches being used analogously to the examples described above.
• vitamin B pyridoxine (vitamin B), nicotinic acid, methionine,
• Citric acid Citric acid, thiamine NO (nitrate) and lysine HCl. '
• the active ingredients described can be incorporated into the swollen starch analogously to vitamin C, as described in Example 5, in order to form a fine powder of encapsulated active ingredient. Since the active substances mentioned behave like fillers in technical polymers, it is also possible to extrude these active substances into swollen starch melts, Table I below examining the corresponding melt, the flowability of the melt and the subsequent cutability resp. are listed.
• the method according to the invention is not only suitable for the coating of medical, cosmetic or pharmaceutical active ingredients, but also for the encapsulation and coating of dye additives, food additives, concrete additives, detergent additives, etc .
• lemon aroma is kneaded cold with dry starch.
• the lemon flavor emulsion contains very volatile components that would evaporate if the temperature were increased.
• the emulsion is absorbed in the starch within 2 minutes, and a yellow powder is produced which smells less of lemon than the emulsion itself. If the powder is heated, it immediately begins to stick and forms pearl gray Bulbs.
• the advantage of the powder produced in this way over the emulsion itself is that the powder can be processed very easily and, above all, is very easy to dose.
• the previously used emulsion on the other hand, is not stable and has to be mixed again and again.
• the emulsion dries out quickly - and loses the aroma when it is open. will let. In contrast, the powder practically does not lose the lemon flavor.
• Example 8 Concrete additives
• the concrete additives are mostly highly viscous, viscous substances that can only be dosed poorly and in particular cannot be mixed homogeneously with the dry cement. If the concrete additives are only added to the already prepared aqueous cement, their effectiveness is immediately started and the cement must be processed immediately.
• Rheobuild 1000 a naphthalene sulfonate (NA salt)
• Rheobuild 2000 a melamine derivative of the following formula:
• Rheobuild SV 87056 a polycarboxylic compound based on polyacrylic acid NA salt, respectively. a copolymer of acrylic acid esters and free acrylic acids and their NA salt,
• liquid concrete additives can be easily kneaded with dry starch without additional swelling agents such as glycerin or amino ethanol. Otherwise glycerin could not be used because of its incompatibility with concrete. Obviously, in the present cases, the active ingredient itself also forms the swelling agent for the starch to swell. After max. 2 minutes, with possible heating, the liquids have been absorbed in their strength, which can occasionally take place with the development of heat.
• the active substances according to Examples 7 and 8 are tabulated in Table II below, their behavior when swelling or. Pulling into the starch has been examined in more detail.
• the active ingredients described in Examples 1 to 8 are representative of an almost unlimited number List of possible active substances and substances which are encapsulated or encapsulated according to the method according to the invention. can be coated, The encapsulation and coating process itself can be modified or modified in any way. be modified.
• a swelling agent which at least partially swells the native starch and, under certain circumstances, an emulsifier, it being necessary for the active substance to be wettable by the swelling agent / starch phase. It is entirely possible that the active ingredient itself serves as a swelling agent. An oil-like substance is preferably also used.

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• Health & Medical Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Bioinformatics & Cheminformatics (AREA)
• Medicinal Chemistry (AREA)
• Pharmacology & Pharmacy (AREA)
• Epidemiology (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Inorganic Chemistry (AREA)
• Nutrition Science (AREA)
• Food Science & Technology (AREA)
• Polymers & Plastics (AREA)
• Medicinal Preparation (AREA)
• Cosmetics (AREA)
• Manufacturing Of Micro-Capsules (AREA)
• Polysaccharides And Polysaccharide Derivatives (AREA)
• Agricultural Chemicals And Associated Chemicals (AREA)
• Formation And Processing Of Food Products (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Medicines Containing Plant Substances (AREA)

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• 1990
  • 1990-01-26 DE DE4002257A patent/DE4002257A1/de active Granted
• 1991
  • 1991-01-24 WO PCT/CH1991/000020 patent/WO1991011178A1/de not_active Ceased
  • 1991-01-24 DK DK91901671.7T patent/DK0468003T3/da active
  • 1991-01-24 AT AT91901671T patent/ATE112164T1/de not_active IP Right Cessation
  • 1991-01-24 KR KR1019910701195A patent/KR920700622A/ko not_active Ceased
  • 1991-01-24 AU AU70531/91A patent/AU633685B2/en not_active Ceased
  • 1991-01-24 ES ES91901671T patent/ES2064078T3/es not_active Expired - Lifetime
  • 1991-01-24 JP JP3502181A patent/JPH04505418A/ja active Pending
  • 1991-01-24 CA CA002050599A patent/CA2050599A1/en not_active Abandoned
  • 1991-01-24 DE DE59103092T patent/DE59103092D1/de not_active Revoked
  • 1991-01-24 EP EP91901671A patent/EP0468003B1/de not_active Revoked
  • 1991-01-26 CN CN91101244A patent/CN1055294A/zh active Pending

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