Abstract: A method for producing a gas microbubble comprises subjecting the gas microbubble to isothermal conditions or cooling conditions such that the lipid-containing shell cools at a rate ranging from about 100° C./min. to about 103° C./min., and wherein said subjecting step transforms the lipid-containing shell from a liquid state to a solid state.
Abstract: Particles comprising
(a) a supercooled melt of a poorly water-soluble substance and
(b) a stabilizing agent,
which have a mean particle size of between 30 and 500 nm, and disperse compositions containing them, as administration forms and delivery systems for drugs, vaccines and other biologically active agents such as herbicides, pesticides, insecticides, fungicides, fertilizers, vitamins, nutrition additives and cosmetics.
Abstract: A method for formulation of high supercoiled DNA content microspheres is described herein. A primary emulsion is formed which optionally contains a DNA nicking inhibitor in addition to DNA with or without buffer. The temperature of the primary emulsion is lowered below the freezing point of the aqueous inner phase which provides increased encapsulation efficiency by decreasing the rate of diffusion of DNA out of the aqueous phase. Thereafter, the primary emulsion is transferred to a water-based surfactant solution and subjected to homogenization to form a secondary microsphere emulsion. The organic phase is removed and the microspheres hardened which are then isolated, frozen and lyophilized.
Type:
Grant
Filed:
December 10, 1998
Date of Patent:
March 6, 2001
Assignee:
Massachusetts Institute of Technology
Inventors:
Shuicho Ando, David Putnam, Robert S. Langer
Abstract: Briefly, according to one aspect of the invention, liquid crystal material is microencapsulated by a method utilizing an interfacial polymerization reaction which creates a combination of polyurethane and polyurea polymers which form the capsule walls surrounding the discrete liquid crystal droplets. The formed capsule walls are designed to have an adjustable refractive index so as to allow for the matching of the refractive index to that of the liquid crystal and polymeric binder materials. This allows for the production of a liquid crystal droplet surrounded by polymer film, which is optically clear when the liquid crystal director is aligned with the electric field. The microencapsulated liquid crystal droplets improves the dye stability of a dichroic dye and enhances the contrast of a liquid crystal display.
Abstract: The invention relates to gel-coated microcapsules which have improved mechanical stress- and flame-resistance. A method for making the gel coated microcapsules is also provided. Phase change materials can be included in the microcapsules to provide thermal control in a wide variety of environments.