Materials and methods relating to polyions and substance delivery
US7319004B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 2003 |
| Grant date | Jan 15, 2008 |
| Priority date | — |
| Expiry date | Jun 2, 2023 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K48/00
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Materials and method are disclose for delivering a desired substance to a target site, using a layered carrier in which the carrier and the substance together form at least three layers which associate by ionic interaction at the first pH, where at least one layer comprises a charge switch material which comprises an ionisable group and which has a positive charge at a first pH and a charge which is less positive, neutral or negative at a second pH, at least one layer comprises a polyionic polymer which is negatively charged at the first pH and at least one layer comprises the desired substance. Preferred carriers are based on the charge switch material poly Bis-Tris and the polyionic polymer polyacrylic acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.