Microparticles

Details Microparticles Microparticles

2005-08-30

2005-08-30

Page, Thurman K. (Department: 1615)

Drug, bio-affecting and body treating compositions

Preparations characterized by special physical form

Particulate form

C424S422000, C424S423000, C424S424000, C424S425000, C424S490000, C424S497000, C424S499000, C424S501000

Reexamination Certificate

active

06936278

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.

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