Chitosan materials from carbonic acid solution
US9925210B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 4, 2015 |
| Grant date | Mar 27, 2018 |
| Priority date | — |
| Expiry date | Feb 4, 2035 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K47/12
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The present invention comprises chitosan materials and methods of using carbonic acid for aqueous solubilization of neutralized or pre-treated chitosan gels and provides, among other things, substantially acid salt free composition native final forms without requiring subsequent acid salt elution. The invention includes chitosan-based solid and semi-solid material forms, optionally reinforced with chitosan fibers, such as powders, fibers, films, matrices, sponges, implants, scaffolds, fillers, and hydrogels. Native final forms are produced from chitosan powder solubilized in an aqueous acidic solution, processed to form a high pH hydrated chitosan gel precipitate material that is then neutralized by water washing and re-solubilized substantially to chitosan solution using carbonic acid. Chitosan materials can be mixed in solution with one or more of other hydrophilic polymers to create compositional heterogeneity and pharmaceutical agents to achieve controlled release of the agent(s) from the final forms at the site of application.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.