Induction of asymmetry in vesicles
US5204112A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 1987 |
| Grant date | Apr 20, 1993 |
| Priority date | — |
| Expiry date | Jun 12, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2984
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Methods are described for controlling the transbilayer distribution of ionizable lipids and proteins in vesicles. Control of the ion gradient of the exterior bathing medium in relation to that of the interior entrapped aqueous compartment of the vesicles induces migration of ionizable lipids or proteins to one or the other of the monolayers comprising the bilayer. This can result in an asymmetric distribution of the ionizable lipid or ionizable protein. The basic ionizable lipids, such as stearylamine and sphingosine, are sequestered into the inner monolayer when the liposome interior is acidic relative to the liposome exterior. Conversely, acidic ionizable lipids such as oleic acid and stearic acid are sequestered into the inner monolayer when the liposome interior is basic relative to the liposome exterior bathing solution. Likewise, phospholipids such as phosphatidylglycerol, phosphatidylinositol, and cardiolipin may also be sequestered into the inner monolayer in response to a relatively acidic exterior medium. Such vesicles may contain bioactive agents and may be administered to mammals including humans.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.