This application concerns novel agents comprising cationic or chemically basic metal chelators in association with hydrophilic carriers of anionic or chemically acidic saccharides, sulfatoids and glycosaminoglycans. In certain embodiments, the agents comprise metals and metal ions. Covalent and...http://www.google.co.uk/patents/US5707604?utm_source=gb-gplus-sharePatent US5707604 - Vivo agents comprising metal-ion chelates with acidic saccharides and glycosaminoglycans, giving improved site-selective localization, uptake mechanism, sensitivity and kinetic-spatial profiles 
