Polymeric microparticles containing agents for imaging
US5562099A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 18, 1994 |
| Grant date | Oct 8, 1996 |
| Priority date | — |
| Expiry date | Aug 18, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S977/753
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Compositions, methods for preparing and methods of using contrast agent-filled polymeric microparticles for imaging are disclosed. In a preferred embodiment, air-encapsulating microparticles are formed by ionotropically gelling synthetic polyelectrolytes such as poly(carboxylatophenoxy)phosphazene, poly(acrylic acid), poly(methacrylic acid) and methacrylic acid copolymers (Eudragit's) by contact with multivalent ions such as calcium ions. In the preferred embodiment, the average size of the microparticles is less than seven .mu.m so that they are suitable for injection intravenously. The polymeric microparticles are stable to imaging and display high echogenicity, both in vitro and in vivo. Due to their in vivo stability their potential application is extended beyond vascular imaging to liver and renal diseases, fallopian tube diseases, detecting and characterizing tumor masses and tissues, and measuring peripheral blood velocity. The microparticles can optionally be linked with ligands that minimize tissue adhesion or that target the microparticles to specific regions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.