Ultrasmall particle of iron oxide – RGD peptidomimetic conjugate as novel MRI contrast agent

Introduction RGD peptidomimetics conjugated to Inand Y-DOTA complexes, and to Gd-DTPA complex, have been recently developed to target the αvβ3 receptor. In this work, we describe the grafting of a new RGD peptidomimetic on ultrasmall particles of iron oxide (USPIO) coated with 3,3’-bis(phosphonate)propionic acid in the context of magnetic resonance molecular imaging.The grafting rates have been evaluated by X-ray photoelectron spectroscopy (XPS) while the USPIO-g-Mimic have been characterized by photon correlation spectroscopy (PCS), magnetometry and NMR relaxometry. Finally their ability to target leukemic cells was also analyzed.