Abstract: Targeting contrast agent for magnetic resonance imaging (MRI). In preferred embodiments, self-assembled polyelectrolytes coated superparamagnetic iron oxide contrast agent particles are provided, which are labeled with targeting moieties, afforded enhanced relaxivity, improved signal-to-noise and targeting ability. Accordingly, the invention relates to a stable targeting contrast nanosystem applicable for magnetic resonance imaging (MRI) having at least one nanoparticle polyelectrolyte polyanion; a targeting agent conjugated to the biopolymer; and a superparamagnetic ligand. In another embodiment the nanosystem according to the invention has at least two biocompatible and biodegradable nanoparticle polyelectrolyte biopolymer. Particularly, the superparamagnetic iron oxide particles are coated by a polyelectrolyte biopolymer and this system self-assembles with the other biopolymer to produce stable nanosystem for magnetic resonance imaging.

Abstract: Macromolecular contrast agents for magnetic resonance imaging are described. Biomolecules and their modified derivatives form stable complexes with paramagnetic ions thus increasing the molecular relaxivity of carriers. The synthesis of biomolecular based nanodevices for targeted delivery of MRI contrast agents are described. Nanoparticles (NP) have been constructed by self-assembling of chitosan (CHIT) as polycation and poly-gamma glutamic acids (PGA) as polyanion. NP's are capable of Gd-ion uptake forming a particle with suitable molecular relaxivity. Folic acid (FA) is linked to the NP's to produce NP-FA bioconjugates that can be used for targeted in vitro delivery to a human cancer cell line.

Abstract: Macromolecular contrast agents for magnetic resonance imaging are described. Biomolecules and their modified derivatives form stable complexes with paramagnetic ions thus increasing the molecular relaxivity of carriers. The synthesis of biomolecular based nanodevices for targeted delivery of MRI contrast agents are described. Nanoparticles (NP) have been constructed by self-assembling of chitosan (CHIT) as polycation and poly-gamma glutamic acids (PGA) as polyanion. NP's are capable of Gd-ion uptake forming a particle with suitable molecular relaxivity. Folic acid (FA) is linked to the NP's to produce NP-FA bioconjugates that can be used for targeted in vitro delivery to a human cancer cell line.