Process for microencapsulating cells
US5286495A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 11, 1992 |
| Grant date | Feb 15, 1994 |
| Priority date | — |
| Expiry date | May 11, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC12N11/04
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Oxalate-degrading enzymes and bacteria were encapsulated for both enteric and intraperitoneal administration. We have shown that via alginate microencapsulation of Oxalobacter formigenes, enzymatic activity was retained for several months. A new process was developed which strengthened the alginate microcapsules and their tolerance to citrate treatment. Much smaller (30-50 .mu.m) alginate microcapsules were made for injection as means of implantation. For oral administration, multi-encapsulated microspheres of cellulose acetate phthalate in poly-2-vinylpyridine (pKa=3.5) were prepared to protect the enzymes from gastric juices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.