Including Vitrification Or Firing Patents (Class 264/43)
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Patent number: 5453280Abstract: A process for producing pellets which are markedly spherical and have a particle size in the range from 0.1 to 4 mm and an apparent density above 0.5 g/cm.sup.3, and which are composed of 90-100% by weight of an ephedrine derivative and 0-10% by weight of a pharmaceutical aid, entails suspending ephedrine derivative powder with an average particle size of from 0.5 to 50 .mu.m at 0.degree.-90.degree. C. with stirring in a water-immiscible non solvent with a boiling point in the range from 60.degree. to 160.degree. C., adding 5-60% by weight, based on the ephedrine derivative, of an agglomerating liquid while continuing stirring, and, if there has been previous heating, cooling to from -5 to 25.degree. C. at 5-40K per hour, with the stirring speed being adjusted after the agglomeration of the powder particles to a value which is necessary for the required average particle size, and removing and drying the resulting pellets.Type: GrantFiled: September 7, 1993Date of Patent: September 26, 1995Assignee: Nordmark Arzneimittel GmbHInventors: Thomas Moest, Uwe Loeffler, Hans Waiblinger
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Patent number: 5453368Abstract: A method for encapsulating a biological substance is biocompatible microcapsules is disclosed, said method comprising:a) maintaining a coating-forming liquid film sheet comprising a solution of a soluble organic polymer in an organic solvent,b) causing droplets comprising biological substance is an aqueous medium to pass through said sheet to form microcapsules comprising cores of said droplets coated by said liquid film, andc) permitting said microcapsules to pass through said sheet so that a portion of said polymer precipitates in the presence of water in said droplets while evaporating a portion of said solvent to form a continuous permeable polymer coating of sufficient structural that said microcapsules are self-supporting.Type: GrantFiled: August 27, 1993Date of Patent: September 26, 1995Assignee: Brown University Research FoundationInventors: Patrick A. Tresco, John F. Mills
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Patent number: 5429780Abstract: A process for preparing a silicon carbide foam by impregnating a polyurethane foam with a suspension of silicon powder in an organic resin, heating progressively to polymerize the resin, heating further to carbonize the polyurethane foam and resin, and finally further heating to carburize the silicon contained in the resin suspension by means of carbon obtained from the carbonization of the foam and resin. The foam obtained is characterized by high macroporosity and a mesoporosity which is variable according to the carburizing temperature.Type: GrantFiled: April 28, 1994Date of Patent: July 4, 1995Assignee: Pechiney RechercheInventors: Marie Prin, Geard Baluais
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Patent number: 5427935Abstract: Material such as biological material is encapsulated within a semi-permeable hybrid membrane bead by suspending the material in a medium which comprises an effective amount of a gelling inducer; forming said suspension into a droplet of a size sufficient to envelop said material, suspending a second material in a gelling solution comprising an effective amount of a gel forming polymer which gels upon contact with said gelling inducer forming a discrete bead by contacting the outer surface portion of the droplet with a gelling solution, and allowing the gelling solution to thicken sufficiently for the second material to become entrapped therein.Type: GrantFiled: June 29, 1993Date of Patent: June 27, 1995Assignee: The Regents of the University of MichiganInventors: Henry Y. Wang, Somesh C. Nigam
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Patent number: 5425993Abstract: Process for obtaining submicronic particles, for example, pigments in the presence of lipidic vesicles having a lamellar structure, starting with at least one precursor of said particles involves preparing a dispersion of vesicles starting with at least one lipid capable of forming the walls of the vesicles and an aqueous phase E intended to be encapsulated in the said vesicles, and optionally an aqueous phase D, intended to form a dispersion medium of the said vesicles, at least one precursor of the said vesicles being dissolved in phase E and/or D, before and/or during and/or after the preparation of the vesicular phase, at least one agent capable of transforming the said precursor(s) into sought after particles being reacted with it (them) after introduction into the preparation medium.Type: GrantFiled: February 19, 1993Date of Patent: June 20, 1995Assignee: L'OrealInventors: Jean-Luc Morancais, Alain Lety, Guy Vanlerbergue
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Patent number: 5422120Abstract: Disclosed are heterovesicular liposomes containing substances of different biologically active compositions each encapsulated in separate chambers of the liposomes, having defined size distribution, adjustable average size, adjustable internal chamber size and number, methods of making them, and treatment of patients with them.Type: GrantFiled: June 16, 1993Date of Patent: June 6, 1995Assignee: DepoTech CorporationInventor: Sinil Kim
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Patent number: 5418010Abstract: A microencapsulation process in which a solid or liquid core material is dispersed in a protein slurry, is heated to create a protein melt and then denatured to bring about encapsulation of the core material and the product of that process.Type: GrantFiled: October 5, 1990Date of Patent: May 23, 1995Assignee: Griffith Laboratories Worldwide, Inc.Inventors: Joseph Janda, Donald Bernacchi, Suzanne Frieders
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Patent number: 5409704Abstract: Aminoglycosides, analogs and derivatives thereof, in the form of phosphate salts are described as well as the process for making and utilizing same. Aminoglycoside phosphate liposomes and nonguanadino aminoglycoside phosphate liposomes, their preparation and use, are particularly described.Type: GrantFiled: May 6, 1993Date of Patent: April 25, 1995Assignee: The Liposome Company, Inc.Inventors: Marcel B. Bally, Lois E. Bolcsak, Pieter R. Cullis, Andrew S. Janoff, Lawrence D. Mayer
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Patent number: 5397759Abstract: Hollow porous microspheres of uniform diameter and of uniform wall thickness are disclosed. The walls of the hollow microspheres comprise sintered together particles which define interconnecting voids within the walls and a single central cavity in the interior of the microspheres and inner and outer microsphere wall surfaces. The interconnecting voids are continuous and extend from the outer wall surface to the inner wall surface. The walls have uniform void content and the interconnecting voids are uniformly distributed in the walls of the hollow microspheres and the walls of the hollow microspheres are free of latent solid or liquid blowing gas materials and are substantially free of relatively thinned wall portions and bubbles. The hollow porous microspheres include microspheres in which the interconnecting voids have been closed and sealed.Type: GrantFiled: July 9, 1992Date of Patent: March 14, 1995Inventor: Leonard B. Torobin
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Patent number: 5395572Abstract: A process for making a structural member wherein bead members are mixed with a selected material and the mixture is compressed and molded into a shape. The compressed mixture is then heated and the bead members removed by melting. The remaining structure, having been thus formed with a plurality of cells therein where the bead members had been removed, can in some embodiments be further heated to a point sufficient to form a strong, lightweight useful structural member, retaining such plurality of cells therein and creating a substantially solid, structural foam member.Type: GrantFiled: September 27, 1993Date of Patent: March 7, 1995Inventor: Gregory R. Brotz
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Patent number: 5395619Abstract: A lipid-polymer conjugate for use in forming long-circulating liposomes is disclosed. The conjugate includes a vesicle-forming lipid having covalently attached to its polar head group, one of the polymers: polyvinylpyrrolidone, polyvinylmethylether, polyhydroxypropyl methacrylate, polyhydroxypropylmethacrylamide, polyhydroxyethyl acrylate, polymethacrylamide, polydimethylacrylamide, polymethyloxazoline, polyethyloxazoline, polyhydroxyethyloxazoline, polyhydroxypropyloxazoline, or polyaspartamide. A method for preparing liposomes containing the lipid-polymer conjugate is also disclosed.Type: GrantFiled: March 3, 1993Date of Patent: March 7, 1995Assignee: Liposome Technology, Inc.Inventors: Samuel Zalipsky, Martin C. Woodle, Danilo D. Lasic, Francis J. Martin
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Patent number: 5393530Abstract: Liposome vesicles are prepared containing water or very dilute solutions encapsulated therein. These "empty" liposomes are suspended in a carrier liquid containing, dispersed therein, substances of interest to be loaded into the vesicles and incubated for a period of time at temperatures above the lipids transition temperature, whereby loading by transmembrane permeation occurs in high yields.Type: GrantFiled: June 22, 1992Date of Patent: February 28, 1995Assignee: Bracco International B.V.Inventors: Michel Schneider, Herve Tournier, Roland Hyacinthe, Christian Guillot, Bernard Lamy
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Patent number: 5387622Abstract: Perfume compositions are formed by hydrolyzing an aqueous mixture of an alkoxide, a silane coupling agent, and a perfume substance using an acid catalyst, then condensing the resulting hydrolysate using a base catalyst, to form a conjugated polymer matrix encapsulating and/or clathrating the perfume substance.Type: GrantFiled: June 28, 1991Date of Patent: February 7, 1995Inventor: Tohru Yamamoto
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Patent number: 5387093Abstract: An apparatus for manufacturing seamless capsules is provided with a multiple nozzle which blows multilayer liquid drops into a hardening liquid. The hardening liquid flows through a main flow path and an auxiliary flow path. The flow of hardening liquid through the main flow path is biased in a direction intersecting the main flow path by a flow of hardening liquid into the main flow path from the auxiliary flow path or a discharge of the hardening liquid from the main flow path into the auxiliary flow path.Type: GrantFiled: December 16, 1993Date of Patent: February 7, 1995Assignee: Freund Inphachem Inc.Inventor: Narimichi Takei
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Patent number: 5385737Abstract: Surfactant-containing seamless capsules of the present invention have an inner layer and an outer layer having a film-forming material. The inner layer contains an oily component and a surfactant component. Such surfactant-containing seamless capsules are produced using in multiple nozzle of triple or more having a sequentially increasing diameter. Since the capsules are excellent in emulsive dispersibility of the content liquid and surfactant dispersibility and solubility in the oily component, they can be used in pharmaceuticals, foods, luxury foods, bath additives, detergents and other fields.Type: GrantFiled: June 10, 1993Date of Patent: January 31, 1995Assignee: Kao CorporationInventors: Chitoshi Shigeno, Naoki Katada, Jun Shida, Norikazu Iwase, Hirotaka Sato, Hidenori Yorozu
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Patent number: 5384290Abstract: Ceramic beads having a bimodal pore distribution are prepared by a process involving a) formation of a ceramic particle slurry, b) adding a foamable prepolymer to the slurry to form a mixture, c) dispersing the mixture as beads in a second liquid, d) polymerizing and foaming the prepolymer, e) recovering the beads and firing them to remove the polymer and bond the ceramic particles. The beads can optionally be joined by sintering. Beads with a monodal pore distribution can be made by using a non-foaming prepolymer.Type: GrantFiled: December 16, 1993Date of Patent: January 24, 1995Assignee: W. R. Grace & Co.-Conn.Inventor: Rasto Brezny
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Patent number: 5382435Abstract: A pharmaceutical composition comprising a shaped enteric material having distributed therethrough preferably substantially uniformly, pharmaceutical loaded particles, said particles having a size no greater than about 10 microns in any dimension and being alkali insoluble and the method of delivering pharmaceuticals to Peyer's glands.Type: GrantFiled: March 24, 1993Date of Patent: January 17, 1995Assignee: Southwest Research InstituteInventors: Richard S. Geary, Herman W. Schlameus
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Patent number: 5378413Abstract: A process for conveniently producing microcapsules containing a gelatin wall crosslinked with quinone and a core of an active compound such as a fouling reducing agent, particularly a tributyl tin chloride, involves use of a simple or complex coacervation technique. The quinone crosslinking provides microcapsules of excellent strength, storage stability, and resistance to aqueous exposure, such that the rate of release of the fouling reducing agent can be controlled with precision.Type: GrantFiled: January 21, 1993Date of Patent: January 3, 1995Assignee: The United States of America as represented by the Secretary of the NavyInventors: James W. Mihm, George I. Loeb, Elizabeth G. Haslbeck
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Patent number: 5376380Abstract: A method of producing liposomal products which comprises treating a positively or negatively charged, freeze- or spray-dried liposomal preparation with an aqueous solution of a drug charged oppositely to the charge of the liposomes.Type: GrantFiled: June 22, 1993Date of Patent: December 27, 1994Assignee: Daiichi Pharmaceutical Co., Ltd.Inventors: Hiroshi Kikuchi, Kiyoto Yachi, Hiromi Morita, Sadao Hirota
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Patent number: 5366733Abstract: Oral compositions for the local administration of a therapeutic agent to a periodontal pocket of a patient for alleviating dental disease comprise a plurality of dry, discrete microparticles each of which comprise an effective amount of at least one therapeutic agent dispersed in a matrix comprising a biocompatible and biodegradable polymer. Apparatus and methods are also provided for the dispensing of the dry microparticles to the periodontal pocket whereby they become tacky and adhere to the involved tissue so as to induce long term therapeutic benefits.Type: GrantFiled: May 28, 1991Date of Patent: November 22, 1994Assignee: American Cyanamid CompanyInventors: Nancy S. Brizzolara, Michael G. Lanzilotti, James R. Lawter
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Patent number: 5364570Abstract: A lightweight ceramic material is provided, useful for example as thermal insulation, kiln furniture or for metallurgical applications.Accordingly, a lightweight fired ceramic material comprises a set porous material in the form of a freeze-gelled ceramic sol composition containing hollow microspheres bonded together in a ceramic matrix.A method of making a lightweight fired ceramic shaped product is also provided in which a freeze-gellable ceramic sol composition is formed containing hollow microspheres, the composition is placed in a tool (21) of high thermal conductivity, the tool is cooled to irreversibly gel the sol composition, the monolith so formed is demoulded and allowed to thaw and is then fired to form a product comprising the microspheres bonded in a ceramic matrix.Type: GrantFiled: November 9, 1992Date of Patent: November 15, 1994Assignee: Foseco International LimitedInventors: Robert Chadwick, Carl Siviter, Anthony D. Farmer
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Patent number: 5362424Abstract: A process for the microencapsulation of oil droplets containing a medical drug for oral administration, comprises the steps of mixing the drug with liquid oil by sonication for 5-30 seconds to disperse the drug homogeneously in the oil, and adding the drug-dispersed oil to an aqueous solution mixture to form a two phase system. The aqueous solution mixture will form a capsule material, and comprises a polysaccharide which has metal chelating capacity, a biocompatible and water-soluble polymer for improving the physical properties of the capsule material, and emulsifying agents. The two phase system is then subjected to sonication to produce an oil-in-water emulsion containing the drug-dispersed oil in the form of droplets having a diameter in the range of 1-5 .mu.m. As soon as possible after formation of the emulsion, the emulsion is added to a multivalent cation-containing solution to harden the capsule material.Type: GrantFiled: October 10, 1991Date of Patent: November 8, 1994Assignee: Korea Research Institute of Chemical TechnologyInventors: Haibang Lee, Soonhong Yuk
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Patent number: 5360614Abstract: A composition of carbohydrates having an edible coating is disclosed, whereby the coated carbohydrate, when orally ingested, causes a time delay release of the carbohydrate into the digestive system. The method of administering carbohydrates in this manner may be useful in the treatment of diseases such as diabetes and exercise programs calling for sustained effort.Type: GrantFiled: April 26, 1993Date of Patent: November 1, 1994Assignee: The Estee CorporationInventors: J. Gary Fox, Darlene Allen
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Patent number: 5344799Abstract: A plastically deformable mixture and method for making a body from the mixture are disclosed. The mixture is composed of powder materials, which when fired form as predominant phases: ceramic, glass-ceramic, glass, and combinations thereof, 0 to an effective amount of burnout agent, water, organic binder which can be cellulose ether, cellulose ether derivatives or combinations thereof, and hydrophilic and hydrophobic additives, to increase the wettability and/or lubricity of the mixture. One advantageous composition for ram extrusion is composed of ceramic-forming powders, water, and in percent by weight based on the powders, about 2% to 8% organic binder which can be methylcellulose, methylcellulose derivatives, and combinations thereof, about 0.3% to 1.0% sodium stearate, and about 0.5% to 2.0% oleic acid.Type: GrantFiled: October 7, 1993Date of Patent: September 6, 1994Assignee: Corning IncorporatedInventor: Shy-Hsien Wu
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Patent number: 5344594Abstract: A method of forming hemispheric bichromal balls, including the steps bringing together two streams of differently colored hardenable liquids for forming a single side-by-side bichromal stream, expelling said single side-by-side bichromal stream into a fluid as one or more free jets whose forward ends becomes unstable and break up into droplets which form into spherical balls, each of the balls comprising hemispheres of differently colored hardenable liquid, and finally hardening the balls.Type: GrantFiled: December 11, 1992Date of Patent: September 6, 1994Assignee: Xerox CorporationInventor: Nicholas K. Sheridon
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Patent number: 5342689Abstract: Microsphere wet cake is mixed with a surface barrier coating effective to prevent agglomeration and surface bonding of the microspheres, and removing water by drying with continuous mixing at high shear. In a subsequent step, by the control of the application of heat and balancing temperature and low shear mixing, it is possible to also control expansion of the microspheres.The surface barrier coating in the present invention is any one of a wide diversity of materials which meet the requirements of the intended function, i.e., to prevent the agglomeration of the microspheres during the process. Suitable materials include, by way of example, dry inorganic pigments or filler materials, and the like, and related organic materials.Type: GrantFiled: October 23, 1992Date of Patent: August 30, 1994Assignee: Pierce & Stevens CorporationInventors: George E. Melber, Leon E. Wolinski, William A. Oswald
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Patent number: 5334381Abstract: Liposomes suitable as ultrasound contrast agents which contain media of various types including gases, gaseous precursors activated by pH, temperature or pressure, as well as other solid or liquid contrast enhancing agents, are described. Methods of using the same as ultrasound contrast agents are also disclosed. The present invention also comprises novel methods for synthesizing liposomes having encapsulated therein gases.Type: GrantFiled: June 30, 1993Date of Patent: August 2, 1994Inventor: Evan C. Unger
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Patent number: 5332584Abstract: A process is disclosed for the microencapsulation of a substantially water-insoluble liquid material within a porous shell to effect a slow rate of release of said material through said shell which comprises (a) providing an organic solution comprising said material and an etherified urea-formaldehyde prepolymer dissolved therein in which from about 50% to about 98% of the methylol groups of said prepolymer have been etherified with a C.sub.4 -C.sub.Type: GrantFiled: December 9, 1991Date of Patent: July 26, 1994Assignee: Zeneca Inc.Inventors: Herbert B. Scher, Marius Rodson
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Patent number: 5330689Abstract: Methods and compositions are described for the preparation of alpha-tocopherol vesicles, the bilayers of which comprise a salt form of an organic acid derivative of alpha-tocopherol such as the Tris salt form of alpha-tocopherol hemisuccinate. The method is rapid and efficient and does not require the use of organic solvents. The alpha-tocopherol vesicles may be used to entrap compounds which are insoluble in aqueous solutions. Such preparations are especially useful for entrapping bioactive agents of limited solubility, thus enabling administration in vivo.Type: GrantFiled: March 29, 1993Date of Patent: July 19, 1994Assignee: The Liposome Company, Inc.Inventors: Andrew S. Janoff, Lois E. Bolcsak, Alan L. Weiner, Paul A. Tremblay, Michael V. W. Bergamini, Robert L. Suddith
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Patent number: 5328628Abstract: This invention relates to a method of stabilizing liposomes contained in aqueous compositions against lysis by anionic surfactants otherwise known to disrupt and lyse such liposomes by using certain surfactants as stabilizing agents and to the stabilized compositions obtained thereby as well as to a method of making detergent compositions containing such stabilized liposomes and anionic surfactants as well as to the compositions themselves. The compositions can be used as shower gels and shampoos. The liposomes are preferably vesicles derived from natural phospholipids or from synthetic nonionic amphiphilic compounds which are sometimes referred to as "niosomes" and may contain water soluble humectants or vitamins. From about 0.Type: GrantFiled: August 26, 1992Date of Patent: July 12, 1994Assignee: S. C. Johnson & Son, Inc.Inventors: Gerald L. Hart, Anjum F. Ahmed, Ursula K. Charaf
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Patent number: 5316771Abstract: An improved simple, efficient, safe, economical, and fast transmembrane ling procedure for efficient active loading of weak amphiphatic drugs into liposomes using the transmembrane gradient. The resulting liposomes loaded with the amphiphatic drug are stable and safe. A storagable form of loadable liposomes has extended period of stability. The reversed procedure is applicable for sustained release of liposome encapsulated drugs from ammonium liposomes.Type: GrantFiled: December 18, 1992Date of Patent: May 31, 1994Assignee: Yissum Research Development Company of the Hebrew University of JerusalemInventors: Yechezkel Barenholz, Gilad Haran
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Patent number: 5308556Abstract: A method of forming an extrusion die fabricated from sinterable ceramic or metal powders, for use in forming honeycomb monolith structures including machining of the die in the green state or after partial densification. Alternatively, all or part of the machining can be performed after full densification or sintering.Type: GrantFiled: February 23, 1993Date of Patent: May 3, 1994Assignee: Corning IncorporatedInventor: Rodney D. Bagley
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Patent number: 5292657Abstract: A process for preparing fatty acid microspheres of microorganisms by rotary disc processing is disclosed. The process is designed to minimize heat risk to the microorganisms during production. Microsphere particles of fatty acid matrix containing microorganisms, preferably stearic acid encapsulated Enterococcus faecium, are also provided.Type: GrantFiled: February 26, 1992Date of Patent: March 8, 1994Assignee: Pioneer Hi-Bred International, Inc.Inventors: William M. Rutherford, Jack E. Allen, Herman W. Schlameus, Donald J. Mangold, William W. Harlowe, Jr., Joseph R. Lebeda
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Patent number: 5290563Abstract: In the method for combining with liposomes heterogeneous substances contained in a mixture, in particular, allergenic substances such as allergens and/or allergenic extracts, contained in an allergenic preparation, by adsorption on the surface of, and/or incorporation in, liposomes which comprise cholesterol, a phospholipid and/or at least one ionic lipid which gives the liposome a positive or negative charge, the liposome or its constituents are combined with the mixture of heterogeneous substances, the pH of the entire combination being higher or lower than the isoelectric point ip of the substances contained in the mixture, depending on whether the ionic lipid is charged positively or negatively respectively.Type: GrantFiled: November 26, 1991Date of Patent: March 1, 1994Assignee: Laboratoire Des StallergenesInventors: Isabelle Millet-Genin, Francis Puisieux, Tran X. Thao, Liliane Roblot-Treupel
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Patent number: 5284588Abstract: A method and system are disclosed for allowing significantly increased migration of a molecule across a lipid bilayer membrane. The method includes combining an aqueous solvent medium, in which the lipid bilayer membrane and the molecule are disposed, with a solute. The aqueous solvent medium, the lipid bilayer membrane and the molecule are then exposed to a sufficient partial pressure of the solute to cause the solute to dissolve in the aqueous solvent medium, whereby a significant portion of the solute migrates to the hydrophobic fatty acyl portion of the lipid bilayer membrane. The solute thereby allows a significantly increased migration of the molecule across the lipid bilayer membrane.Type: GrantFiled: January 8, 1992Date of Patent: February 8, 1994Assignees: Trustees of Boston University, General Electric CompanyInventors: Lee C. Makowski, Hoshang F. Batliwala
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Patent number: 5283015Abstract: A process for forming microcapsules having discrete capsule walls comprising the steps of:forming an emulsion of an oily core material phase in a continuous aqueous phase, said oily core material phase including isocyanatoacrylate or cyanoacrylate prewall reactants which react with said aqueous phase to form a pre-wall material around said oily core material phase; andenwrapping particles of said oily core material phase in an amine-formaldehyde condensation product produced by in situ condensation of an amine and formaldehyde, and the microcapsules produced thereby are disclosed.Type: GrantFiled: January 25, 1991Date of Patent: February 1, 1994Assignee: The Mead CorporationInventors: David A. Hutchings, Margaret T. Thomas, William A. Hammann, IV, Rong-Chang Liang
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Patent number: 5283122Abstract: Liposomes containing phosphatidylethanolamine, palmitoyl homocysteine or oleic acid or palmitic acid, fuse rapidly when the pH of the medium is reduced below 7. Liposome fusion was measured by (a) mixing of the liposomal lipids as shown by resonance energy transfer, (b) gel filtration and (c) electron microscopy. The presence of phosphatidylethanolamine or acid addition esters thereof in the liposomes greatly enhances fusion; whereas the presence of phosphatidylcholine inhibits fusion. During fusion of liposomes containing phosphatidylethanolamine:palmitoyl homocysteine (8:2), almost all of the encapsulated calcein is released. Inclusion of cholesterol (40%) in the liposomes substantially decreases leakage without impairing fusion. Those pH sensitive liposomes are fused to deliver biologically active molecules such as DNA, into living cells.Type: GrantFiled: February 14, 1992Date of Patent: February 1, 1994Assignee: University of Tennessee Research CorporationInventors: Leaf Huang, Jerome Connor
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Patent number: 5283016Abstract: The present invention is directed to an improved method for forming photosensitive microcapsules and increasing sensitivity by incorporating a thiol into the microcapsules through diffusion while maintaining an aqueous surrounding medium at a pH of 7.0 or less.Type: GrantFiled: March 9, 1989Date of Patent: February 1, 1994Assignee: The Mead CorporationInventors: Paul Davis, Jacqueline G. Truini
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Patent number: 5277914Abstract: Liposome and lipidic particle formulations of compounds are prepared by dissolving in a solution of liposome-forming lipids in an aprotic solvent such as DMSO, optionally containing a lipid-solubilizing amount of a lower alkanol, and either injecting the resulting solution into an aqueous solution, or the aqueous solution into the resulting solution. The resulting liposome or lipidic particle suspension may then be dialyzed or otherwise concentrated. This method is particularly useful for compounds which are poorly-soluble in aqueous solution, but is generally useful for any compound or combination of compounds which can be dissolved in the aprotic solvent or aprotic solvent/lower alkanol mixture.Type: GrantFiled: August 8, 1991Date of Patent: January 11, 1994Assignee: The Regents of the University of CaliforniaInventor: Francis C. Szoka, Jr.
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Patent number: 5277979Abstract: A process for encapsulating a wide variety of target materials, including both hydrophilic and hydrophobic materials, employs condensation of two reactive compounds to form shells around core phase particles including target material dispersed in a continuous phase. One of the reactive compounds has at least two active methylene functional groups per molecule, the other being an active methylene-reactive crosslinking agent. Either type of the reactive compounds can be dispersed in the continuous phase, the other being dispersible in the core phase. Applications include controlled release microencapsulation of agriculture chemicals and biocides.Type: GrantFiled: May 13, 1992Date of Patent: January 11, 1994Assignee: Rohm and Haas CompanyInventors: Andrew J. Kielbania, Jr., William D. Emmons, George H. Redlich
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Patent number: 5262168Abstract: A liposome composition and methods for making same are disclosed, such compositions comprise an arachidonic acid metabolite such as a prostaglandin, preferably prostaglandin E.sub.1, a lipid, and a drying protectant such as a saccharide. The liposomes may be loaded with prostaglandin passively, or using a transmembrane concentration gradient, preferably using a transmembrane pH gradient. Using this transmembrane loading technique, trapping efficiencies of 50% to 100% are achieved, and the release rate of the prostaglandin from the liposomes is reduced. The liposome size is maintained after lyophilization and reconstitution.Type: GrantFiled: January 16, 1992Date of Patent: November 16, 1993Assignee: The Liposome Company, Inc.Inventors: Robert P. Lenk, Michelle L. Tomsho, Robert L. Suddith, Robert J. Klimchak
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Patent number: 5260002Abstract: The present invention relates to a method and apparatus for producing uniform polymeric spheres with controllable permeability. This invention may be useful for encapsulating living cells or tissue or chemicals or medicines in uniform polymeric spheres. In particular, this invention relates to polymeric microspheres made from polycation and polyanion polymer solutions. An apparatus includes airtight housing 1 having top 3 and bottom 25 chambers. Top chamber 3 includes pressure regulator means 5, stationary polyanion reservoir tank 7, polycation reservoir tank 27, and feed line 9 to adjustable tank 11. Tank 11 is associated with oscillator 13, nozzle 14 and capacitance means 19. Nozzle 14 and oscillator 3 cooperate to form polyanion droplets. In the bottom chamber 25 annular nozzle 50 is used to form an annular jet of polycation solution. The droplets and polycation jet are mixed at minimal impact velocities to form uniform polymeric sphere.Type: GrantFiled: December 23, 1991Date of Patent: November 9, 1993Assignee: Vanderbilt UniversityInventor: Taylor G. Wang
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Patent number: 5258150Abstract: A body is made up of at least about 93% by weight cordierite, having a coefficient of thermal expansion of no greater than about 4.times.10.sup.-7 .degree.C.sup.-1, from about 25.degree. C. to about 800.degree.0 C., and a total porosity of greater than about 42%. A method for producing the body which includes selecting raw materials to form a composition which forms cordierite on firing, the raw materials being composed of: talc having a BET surface area of no greater than about 5 m.sup.Type: GrantFiled: December 6, 1991Date of Patent: November 2, 1993Assignee: Corning IncorporatedInventors: Gregory A. Merkel, Martin J. Murtagh
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Patent number: 5252263Abstract: Methods are described for controlling the transbilayer distribution of ionizable lipids and proteins in vesicles. Control of the ion gradient of the exterior bathing medium in relation to that of the interior entrapped aqueous compartment of the vesicles induces migration of ionizable lipids or proteins to one or the other of the monolayers comprising the bilayer. This can result in an asymmetric distribution of the ionizable lipid or ionizable protein. The basic ionizable lipids, such as stearylamine and sphingosine, are sequestered into the inner monolayer when the liposome interior is acidic relative to the liposome exterior. Conversely, acidic ionizable lipids such as oleic acid and stearic acid are sequestered into the inner monolayer when the liposome interior is basic relative to the liposome exterior bathing solution.Type: GrantFiled: March 17, 1992Date of Patent: October 12, 1993Assignee: The Liposome Company, Inc.Inventors: Michael J. Hope, Pieter R. Cullis
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Patent number: 5250236Abstract: Solid lipid microspheres having a diameter lower than one micron and a polydispersion of between 0.06 and 0.90 obtained by adding to a molten lipid substance a mixture consisting of water, a surfactant and possibly a co-surfactant, dispersing in water the obtained microemulsion, washing with water the dispersion microspheres by diafiltration and lyophilizing.Type: GrantFiled: August 2, 1991Date of Patent: October 5, 1993Inventor: Maria R. Gasco
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Patent number: 5244672Abstract: The invention relates to a composition containing liposomes, stabilized by a stabilizing support comprising a mixture of atelocollagen and glycosaminoglycans in a relative proportion preferably ranging between 18 and 25% by weight of the atelocollagen. The preferred use of this composition is in pharmacy or beauty care.Type: GrantFiled: November 6, 1991Date of Patent: September 14, 1993Assignee: ColeticaInventors: Alain Huc, Chantal Buffevant, Daniel Herbage
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Patent number: 5232780Abstract: In microcapsules with a polymeric capsule wall, the polymer of the capsule wall comprises thermolabile predetermined breaking points in the form of hexamethylenetetramine or acetaldehyde ammonia derivatives in order to facilitate release of the capsule contents (various active substances, such as example, dyes, medicaments, developers, curing agents, flameproofing agents) in a specific manner by exposure to heat.Type: GrantFiled: December 18, 1991Date of Patent: August 3, 1993Assignee: Siemens AktiengesellschaftInventors: Oskar Nuyken, Brigitte Voit, Jochen Dauth
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Patent number: 5230899Abstract: Liposome-forming materials containing a long chain aliphatic or aromatic-based acid or amine, hydrating agents and discrete amounts of water form gels which are useful drug delivery systems and spontaneously form highly stable liposomes in aqueous solution having very high capture efficiency.Type: GrantFiled: June 14, 1991Date of Patent: July 27, 1993Assignee: SmithKline Beecham CorporationInventors: John Y. Park, Shurl A. Thompson
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Patent number: 5230953Abstract: Silica particles having an average particle size of 5 to 100 .mu.m, a BET specific surface area of not more than 20 m.sup.2 /g and a pore volume of not more than 0.1 ml/g, each of which has on its surface a plurality of protuberances with a smooth configuration , a diameter at half the protuberance height of the said protuberance being 0.2 to 5.0 .mu.m and a height of the said protuberance being 0.2 to 4.0 .mu.m, and a process for producing the silica particles, which comprises (A) reacting hydrosilicofluoric acid, ammonium silicofluoride or a mixture thereof with ammonia in an aqueous medium to form a silica slurry, (B) separating a silica from the silica slurry, and (C) calcining, after optionally drying, the separated silica at a temperature of not less than 500.degree. C.Type: GrantFiled: December 11, 1990Date of Patent: July 27, 1993Assignee: Nissan Chemical Industries Ltd.Inventors: Makoto Tsugeno, Yasushi Takako, Masao Kubo, Tokumi Mochiyama, Yoshito Yuri
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Patent number: 5229046Abstract: There is provided a thermal shock-resistant silicon nitride sintered material including silicon nitride and rare earth element compounds, which material contains at least 10 pore groups per mm.sup.2, each pore group consisting of pores of 10 or less in diameter and which material has a thermal shock resistance .DELTA.Tc (.degree.C.) of 1,000.degree. C. or more. The thermal shock-resistant silicon nitride sintered material can be produced by mixing and shaping starting materials consisting of silicon nitride powders of rare earth element oxides and carbide powder, and then firing the shaped material in a nitrogen atmosphere to decompose the carbide powders.Type: GrantFiled: November 5, 1991Date of Patent: July 20, 1993Assignee: NGK Insulators, Ltd.Inventors: Keiichiro Watanabe, Akira Takahashi