Patent · US Expired

Microparticles

US6936278B2 · kind B2 · utility

2Cited by
26References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 6, 2002
Grant dateAug 30, 2005
Priority date
Expiry dateFeb 10, 2023

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61K9/5073
  • WIPO fieldPharmaceuticals
  • WIPO sectorChemistry

Abstract

A process for producing microparticles, in which an aqueous solution of purified amylopectin-based starch of reduced molecular weight is prepared, the solution is combined with biologically active substance, an emulsion of starch droplets is formed in an outer phase of polymer solution, the starch droplets are made to gel, the gelled starch particles are dried, and a release-controlling shell is optionally applied to the particles, wherein at least one buffer substance having the ability of keeping the pH of the produced microparticles above 3 if exposing the microparticles to an aqueous evironment is added at any stage during the process.Microparticles which essentially consist of said starch, have an amino acid content of less than 50 μg and have no covalent chemical cross-linking and which have the aktivity of keeping the pH above 3 if exposed to a aqueous environment.

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