{
  "patent_number": "US 4235871",
  "country": "US",
  "title": "How to Encapsulate Active Materials in Lipid Bubbles Efficiently",
  "original_title": "Method of encapsulating biologically active materials in lipid vesicles",
  "summary": "This patent describes a method for trapping biologically active substances inside tiny, multi-layered fat bubbles called liposomes, using a specific water-in-oil emulsion and gel-forming process to improve how much material gets captured.",
  "what_it_does": "This patent details a four-step method for encapsulating biologically active materials within synthetic, oligolamellar lipid vesicles (liposomes). First, it involves providing a mixture of a wall-forming compound (like a phospholipid, per claim 2) in an organic solvent and an aqueous mixture of the material to be encapsulated. This is then formed into a homogeneous water-in-oil type emulsion, as specified in claim 1. Next, the organic solvent is evaporated from this emulsion until it becomes a gel-like mixture. Finally, this gel is converted into a suspension of liposomes by either agitating the gel or dispersing it in an aqueous medium, effectively trapping the active material inside. For example, insulin (claim 20) could be encapsulated using this method.",
  "what_it_does_not_cover": [
    "Does not cover encapsulation methods that do not form a water-in-oil type emulsion as an intermediate step.",
    "Does not cover methods that do not involve evaporating an organic solvent to create a gel-like mixture.",
    "Does not cover forming liposomes that are not 'oligolamellar' (having a few layers), such as single-layered or highly multi-layered vesicles.",
    "Does not cover methods where the biologically active material is not initially in an aqueous mixture.",
    "Does not cover methods where the wall-forming compound is not initially provided in an organic solvent."
  ],
  "filed": "1978-02-24",
  "granted": "1980-11-25",
  "expires": null,
  "status": "active",
  "holder": "Individual",
  "holder_url": "https://patentbrief.org/company/individual",
  "inventors": [
    {
      "name": "Demetrios P. Papahadjopoulos",
      "url": "https://patentbrief.org/inventor/demetrios-p-papahadjopoulos"
    },
    {
      "name": "Francis C. Szoka, Jr.",
      "url": "https://patentbrief.org/inventor/francis-c-szoka-jr"
    }
  ],
  "times_cited": 1862,
  "tags": [
    "biotech",
    "pharmaceutical",
    "materials"
  ],
  "abstract": "The disclosure is of a method for encapsulating biologically active materials in synthetic, oligolamellar lipid vesicles (liposomes). The method comprises providing a mixture of lipid in organic solvent and an aqueous mixture of the material for encapsulation, emulsifying the provided mixture, removing the organic solvent and suspending the resultant gel in water. The method of the invention is advantageous over prior art methods of encapsulating biologically active materials in that it provides a means for a relatively high capture efficiency of the material for encapsulation. The disclosure is also of intermediate compositions in the encapsulation method, the product vesicles, compositions including the product vesicles as an active ingredient and their use.",
  "url": "https://patentbrief.org/patent/us/4235871/hepatitis-b-vaccine-recombivax",
  "markdown_url": "https://patentbrief.org/patent/us/4235871/hepatitis-b-vaccine-recombivax/md",
  "google_patents_url": "https://patents.google.com/patent/US4235871",
  "relatedPatents": []
}