Patent ID: 7235227
Filing Date: 2007-06-26
Classification: A61K,B82Y

Abstract:
1. A contrast agent for magnetic resonance imaging (MRI), which agent comprises particles, wherein said particles are coupled to a chelator containing a paramagnetic ion which ion is positioned offset from the surface of the particles by a tether, so as to provide said ion substantial access to hydrogen nuclei in a surrounding liquid, whereby the relaxivity of said nuclei is enhanced, wherein said particles are microparticles or nanoparticles comprised of an inert core comprising a perfluorocarbon compound, an animal oil, a vegetable oil, a mineral oil, a protein or a polymer surrounded by a lipid/surfactant coating, and wherein said chelator is positioned offset from the surface of the particles through said tether which tether is covalently bound to said chelator and to at least one component of the particles, and wherein the tether contains at least one site susceptible to cleavage.