Facile One-Pot Synthesis of Intrinsically Radiolabeled 64Cu-Human Serum Albumin Nanocomposite for Cancer Targeting

Development of suitably radiolabeled nanoplatforms for cancer targeting is still at an early stage necessitating a simplified and reliable approach for incorporation of radioisotopes onto nanoparticles with minimal impact on their original biological behavior. In this study, we have developed an one-pot synthesis protocol for preparation of small sized (4-5 nm diameter), water soluble, intrinsically radiolabeled Cu-64 metal nanoparticles capped within human serum albumin (HSA) scaffold (Cu-64-HSA nanocomposite). Detailed characterization of the as-synthesized nanoparticles was carried out by various analytical techniques to establish the colloidal and radiochemical stability, biocompatibility and suitability for clinical administration. The biological efficacy of Cu-64-HSA nanocomposite was demonstrated by biodistribution studies in melanoma tumor bearing C57BL/6 mice, that showed rapid diffusion and accumulation of the radiotracer into tumor and clearance from the biological system by both renal and hepatobiliary routes. The promising results obtained in this study suggest that this strategy could be employed to facilitate clinical translation of a new class of biocompatible radiotracers derived from metal-based nanoparticles for PET imaging.