Contrast agents

US5558857A · kind A · utility

Assignee

• NYCOMED IMAGING AS · NO

Inventors

• Jo Klaveness · Oslo, NO
• Pal Rongved · Oslo, NO
• Per Strande · Oslo, NO

Key dates

• Filing date: Dec 23, 1993
• Grant date: Sep 24, 1996
• Expiry date: Dec 23, 2013

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61K49/223
• WIPO field: Pharmaceuticals
• WIPO sector: Chemistry

Abstract

This invention relates to ultrasound contrast agents in the form of microparticles comprising a biotolerable matrix (e.g. of a carbohydrate or an X-ray contrast agent) in association with a gas or a precursor therefor. The contrast agents are stabilized to enhance their in vivo stability and/or echogenicity by covalently modifying the structure of the matrix, e.g. to introduce crosslinking groups or to attach lipophilic groups and/or molecules. The covalent moieties may include biodegradable linkages to assist rapid subsequent elimination of the contrast agents from the system.