Method for preparing microcapsules comprising active materials coated with a polymer and novel microcapsules in particular obtained according to the method
US6183783A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 1999 |
| Grant date | Feb 6, 2001 |
| Priority date | — |
| Expiry date | Jun 22, 2019 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K9/1694
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The invention concerns a method for preparing microcapsules containing an active substance coated with a substantially polar polymer film, characterized in that it consists in the following steps: suspending an active substance insoluble in a substantially polar polymer solution in an organic solvent, said substantially polar polymer being insoluble in liquid or supercritical CO.sup.2, said organic solvent being soluble in liquid or supercritical CO.sup.2 ; contacting the suspension with liquid or supercritical CO.sup.2 so as to extract the solvent from the polymer in a controlled manner and ensure the coacervation of the polymer; substantially extracting the solvent by means of supercritical CO.sup.2 and draining off the CO.sup.2 /solvent mixture; recuperating the microcapsules in the form of dry powder. The invention also concerns microcapsules containing an active substance coated with a substantially polar polymer selected among the group consisting of polysaccharides, cellulose derivatives, acrylic, methacrylic polymers or derivatives of esters of vinyl, polyesters, polyamides, polyanhydrides, polyorthoesters and polyphosphazenes, characterized in that the polymer film has low…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.