Manufacturing protein microspheres
Patent 5069936 Issued on December 3, 1991. Estimated Expiration Date: 
August 7, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
August 7, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3540532 3663685 Injectable compositions, nanoparticles useful therein, and process of manufacturing same Biological materials Patent #: 4269821 InventorApplicationNo. 390628 filed on 08/07/1989US Classes:427/213.33, Using crosslinking agent264/4.1, Liquid encapsulation utilizing an emulsion or dispersion to form a solid-walled microcapsule (includes liposome)264/4.3, With treatment subsequent to solid wall formation (e.g., coating, hardening, etc.)424/1.25, Dissolving or eluting from solid or gel matrix (e.g., capsule, tablet)424/1.33, Delivery to active site involves particle dissolving, degrading, or otherwise releasing of radionuclide424/484, Matrices424/491, Containing proteins and derivatives428/402.2, Microcapsule with fluid core (includes liposome)428/402.24, Microcapsule with solid core (includes liposome)514/6, Heavy metal containing (e.g., hemoglobin, etc.)514/885, IMMUNE RESPONSE AFFECTING DRUG514/965Discrete particles in supporting matrixExaminersPrimary: Lovering, Richard D.Attorney, Agent or FirmInternational ClassesA61K 009/26A61K 009/64 B01J 013/08 B01J 013/20 AbstractProcesses for producing biocompatible and biodegradable protein microspheres with controlled porosity and microsphere sizes are disclosed. Generally, the processes are accomplished as follows: (a) dissolving a source of protein in a mildly acidic or basic aqueous medium, in the presence or absence of a biomodifying agent, (b) adding a cross-linking reagent to the dissolved protein molecules in an amount effective subsequently to cross-link the protein molecules without gelation; (c) adding a water soluble surfactant to modify the surface of the partially cross-linked protein molecules, (d) adding a water soluble organic desolubilizer to desolubilize the protein molecules to allow cross-linkage of nearby protein molecules into water-insoluble microspheres. Alternatively, the cross-linking step of (b) is employed after desolvation of the microspheres. Incorporation of the biomodifying agent, if any, can be achieved by prior bonding to the protein molecules, addition during the formation of microspheres, or addition after the formation of the irreversible and stable microspheres. The microspheres produced by said processes are also disclosed.Other References
Field of SearchLiquid encapsulation utilizing an emulsion or dispersion to form a solid-walled microcapsule (includes liposome)With treatment subsequent to solid wall formation (e.g., coating, hardening, etc.) Using crosslinking agent Microcapsule with fluid core (includes liposome) Microcapsule with solid core (includes liposome) Containing proteins and derivatives Discrete particles in supporting matrix | |
