Synthesis and characterization of dextran stabilized superparamagnetic iron oxide nanoparticles for in vivo MR imaging of liver fibrosis.

The field of medical imaging has recently seen rapid advances in the development of novel agents for enhancing image contrast. In particular, superparamagnetic iron oxide nanoparticles (SPIONs) with a variety of surface properties have been tried as effective contrast agents for magnetic resonance imaging, but with major side effects. In this study, the surface chemistry of SPIONs of size 12 nm was modified with high molecular weight dextran to yield particles of size 50 nm, without compromising the magnetic properties. A systematic characterization of the material for its size, coating efficiency, magnetic properties and biocompatibility has been carried out. The magnetic relaxivity as evaluated on a 1.5 T clinical magnet showed r2/r1 ratio of 56.28 which is higher than that reported for any other dextran stabilized ironoxide nanoparticles. Liver uptake and magnetic resonance imaging potential of dextran stabilized SPIONs (D-SPIONs) has been evaluated on liver fibrosis induced animal model, which is further supported by histopathology results.