×

Microencapsulation of living tissue and cells

  • US 4,806,355 A
  • Filed: 06/08/1987
  • Issued: 02/21/1989
  • Est. Priority Date: 06/06/1983
  • Status: Expired due to Term
First Claim
Patent Images

1. A biocompatible in microcapsule, suitable for implantation into an animal body and having a diameter of about 50 to about 2000 μ

  • m, comprising;

    a macromolecular spherical core containing living tissue or individual cells thereof, said core being surrounded by of interpenetrating layers of ionically-interacted biocompatible materials defining a membrane thickness of about 5 to about 20 μ

    m, said biocompatible materials comprising a biocompatible polyamino acid polymer normally having a positively-charged surface and a non-toxic biocompatible water-soluble polymeric material which is capable of ionic interaction with free amino groups in said polyamino acid to provide an outer biocompatible negatively-charged surface, said biocompatible semi-permeable membrane being in the form of a hydrogel having an overall water content within the membrane structure of at least about 20 wt. %,said biocompatible semi-permeable membrane being permeable to and permitting nutrients and oxygen to flow from a body in which the microcapsule is implanted to said living tissue of individual cells thereof and permitting metabolic products of said living tissue to flow therefrom to the body in which the microcapsule is implanted and being impermeable to said living tissue to retain the living tissue within the microcapsule, said microcapsule being capable of resisting degradation and remaining permeable in vivo for at least two months.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×