Biodegradable bursting release system
US5429822A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 13, 1992 |
| Grant date | Jul 4, 1995 |
| Priority date | — |
| Expiry date | Mar 13, 2012 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K9/0024
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
A biodegradable polymeric multiphasic release system of one or more biodegradable bursting units capable of delivering biologically active substances in a burst or pulse at predetermined times and a method for constructing those units is disclosed. The individual bursting units of the system may take the form of a biodegradable, membrane coated capsule surrounding a core material which may include an active agent. The membrane ruptures after a predetermined time upon exposure to water or bodily, or other aqueous environmental fluids. The bursting units may be used in any situation in which a controlled pulsed release of an active substance is desired. The predetermined time release of each bursting unit is controlled by the composition of the core material, the initial radius and wall thickness of the membrane and the porosity of the membrane. The core material may also contain a chemical composition which generates gas as fluid is drawn into the bursting unit thus adding an additional design variable for predetermining bursts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.