Preparation method for biodegradable polymeric microspheres using solvent extraction and preparation method for microspheres for treating local inflammation using the same

{
  "publication_number": "US6149944A",
  "country": "US",
  "kind": "A",
  "title": "Preparation method for biodegradable polymeric microspheres using solvent extraction and preparation method for microspheres for treating local inflammation using the same",
  "abstract": "PCT No. PCT/KR97/00055 Sec. 371 Date Aug. 2, 1999 Sec. 102(e) Date Aug. 2, 1999 PCT Filed Apr. 1, 1997 PCT Pub. No. WO97/36949 PCT Pub. Date Oct. 9, 1997A preparation method for biodegradable polymeric microspheres using a solvent extraction method for biodegradable polymeric microspheres for treating a local inflammation disease using the same which are capable of effectively curing ozena such as sinusitis and a middle ear infection. Since a non-solvent of polymer is added into an outer aqueous phase in advance, the solidification of the polymer is implemented in a short time which, in turn, improves encapsulation of the therapeutic agent used.",
  "claims": [
    "1. A preparation method for a biodegradable polymeric microspheres for treating local inflammation disease, comprising: a step for preparing a W/O emulsion by mixing an inner aqueous phase containing water-soluble betalactam antibiotic agent and/or an inhibitor of betalactamase and an organic phase comprising an organic solvent of polymer in which a biodegradable polymer is dissolved, well dispersing the resulting emulsion; a step for preparing an outer aqueous phase wherein a non-solvent of the polymer is dissolved in an aqueous solution of distilled water containing a surface active agent; a step for adding the aforementioned W/O emulsion into the said outer aqueous phase to prepare a W/O/W emulsion; and a step for removing the organic solvent of the polymer.",
    "2. The method of claim 1, wherein said betalactam antibiotic agent is ampicillin, amoxycilin, or salts thereof, and said inhibitor of a betalactamase is sulbactam, clavulanic acid or salts thereof."
  ],
  "description_excerpt": "This application is a 371 continuation of PCT/KR97/00055 filed Apr. 1, 1997, which is a continuation of KR19669755 filed Apr. 1, 1996.\n\nThe present invention relates to an improved preparation method for a biodegradable polymeric microspheres using a solvent extraction method and a preparation method for biodegradable polymeric microspheres for treating local inflammation disease, in particular, for treating sinusitis and middle ear inflammation.\n\nEsters, especially a single or combined polymeric esters consisting of a single molecule of a lactic acid and a glycolic acid have received much attention in the development of a sustained medicine delivery system due to their high biocompatibility, biodegradability and applicability for the human body as recognized for its stable usage as suture. Generally, they have been employed in the form of microspheres, transplantates, and fibers. Various microspheres preparation methods using a biodegradable polymeric ester have been reported. Among these, a solvent evaporation method is widely used. This method is directed to dissolving a polymer in a proper solvent and then dissolving or dispersing a therapeutic agent, which in turn, is dispersed in an aqueous phase containing a surface active agent. Thereafter, it is heated to evaporate the solvent of the polymer to obtain microspheres.",
  "cpc": [
    "A61K 9/1694",
    "A61K 9/1647",
    "A61K 9/50",
    "A61P 43/00",
    "C08J 3/16"
  ],
  "ipc": [
    "A61K 31/397",
    "A61K 31/43",
    "A61K 47/34",
    "A61K 9/113",
    "A61K 9/16",
    "A61K 9/50",
    "C08J 3/16"
  ],
  "assignees": [
    "Korea Institute of Science and Technology KIST"
  ],
  "inventors": [
    "Seo Young Jeong",
    "Ick Chan Kwon",
    "Yong-Hee Kim"
  ],
  "filing_date": "1997-04-01",
  "publication_date": "2000-11-21",
  "grant_date": "2000-11-21",
  "priority_date": "1996-04-01",
  "application_number": "US-15562999-A",
  "family_id": "19454795",
  "cited_by_count": 58,
  "citations": [
    "US5478564A",
    "US5445832A",
    "EP0595030A2",
    "US5753234A"
  ]
}