Patent · US Expired

Encapsulation by entrapment

US4344857A · kind A · utility

51Cited by
8References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 16, 1980
Grant dateAug 17, 1982
Priority date
Expiry dateMay 16, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/2989
  • WIPO fieldPharmaceuticals
  • WIPO sectorChemistry

Abstract

Chemical biological agents to be encapsulated are dissolved or dispersed in an aqueous solution of polyhydroxy polymer xanthate. Simultaneous addition of a strong acid and a coupling agent to the solution insolubilizes the polyhydroxy polymer without degrading the xanthate moiety, thereby entrapping the agents in a protective matrix. Encapsulation of biologically active compositions provides a shield against hostile environments, improves safety in handling, and slows the release of such compounds to the surrounding medium. Highly volatile liquids are protected against losses by evaporation. Encapsulation also provides protection against decomposition from exposure to ultraviolet light.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.