Preparation and uses of multi-phase microspheres
US5288502A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 1991 |
| Grant date | Feb 22, 1994 |
| Priority date | — |
| Expiry date | Oct 16, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2987
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Multi-phase polymeric microspheres containing a molecular compound dispersed in a polymeric matrix are described. Methods for preparing the multi-phase microspheres are also described, which includes a multiple emulsion solvent evaporation technique. Drug loading efficiencies between 80 to 100% were achieved using the described methods. Particular ratios of the W/O emulsion to polymer, and concentration of surfactant and dispersion media (mineral oil) provide highly efficient multi-phase microspheres. In particular embodiments, the multi-phase microspheres feature a high loading efficiency of water-soluble drugs, and also eliminates partitioning of the water soluble agent into the polymer acetonitrile (solvent) phase, thus preventing low encapsulation efficiency. The described multi-phase microspheres possess efficient drug loading, release properties, and drug stability, and also provide a vehicle for long term therapeutic release of a biologically active molecule for therapeutically effective periods of time. Molecular compounds which may be incorporated within the multi-phase microspheres include both water-soluble and water-insoluble drugs, proteins (e.g. TNF), peptides, and ch…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.