A new theranostic system for bone disorders: Functionalized folate-MDP hydroxyapatite nanoparticles with radiolabeled copper-64

Hydroxyapatite nanoparticles have been investigated as biological agents for the treatment and diagnosis of bone diseases due to their properties, providing high affinity to bone tissues and also due to the possibility to chemically modify the surfaces of these nanoparticles to provide active targeting to bone tumors or other bone disorders. In this work, synthetic hydroxyapatite nanoparticles and their surface modifications with folic and medronic acid were studied. Copper-64 was produced by neutron irradiation in a TRIGA MARK I nuclear reactor, and the functionalized nanoparticles radiolabeled with this radioisotope. The multi-technique characterization includes FTIR, PXRD, TGA, DSC, CHN, Zeta potential, XPS, SEM, TEM, and Gamma spectroscopy. Furthermore, the evaluation of the chemical interaction stability was through leaching tested for efficiency. The results indicate that folic and medronic acids can be covalently bonded to HA surface, producing a new material not yet described in the literature, been stably attached to hydroxyapatite nanoparticle surfaces, able to provide active targeting for bone disorders. The complexation of copper-64 provides high radiochemistry purity, although the specific activity must be improved. [Display omitted] •Folate moiety was aminated and covalently bond to medronate molecule.•Synthetic hydroxyapatite nanoparticles were functionalized with folate-medronate.•Copper-64 radioisotope was produced by neutronic activation in a nuclear reactor.•Hydroxyapatite-folate-medronate nanoparticles were radiolabeled with copper-64.