Gum arabic as a phytochemical construct for the stabilization of gold nanoparticles: in vivo pharmacokinetics and X-ray-contrast-imaging studies.

Gold nanoparticles (AuNPs) have exceptional stability against oxidation and therefore will play a significant role in the advancement of clinically useful diagnostic and therapeutic nanomedicines. Despite the huge potential for a new generation of AuNP-based nanomedicinal products, nontoxic AuNP constructs and formulations that can be readily administered site-specifically through the intravenous mode, for diagnostic imaging by computed tomography (CT) or for therapy via various modalities, are still rare. Herein, we report results encompassing: 1) the synthesis and stabilization of AuNPs within the nontoxic phytochemical gum-arabic matrix (GA-AuNPs); 2) detailed in vitro analysis and in vivo pharmacokinetics studies of GA-AuNPs in pigs to gain insight into the organ-specific localization of this new generation of AuNP vector, and 3) X-ray CT contrast measurements of GA-AuNP vectors for potential utility in molecular imaging. Our results demonstrate that naturally occurring GA can be used as a nontoxic phytochemical construct in the production of readily administrable biocompatible AuNPs for diagnostic and therapeutic applications in nanomedicine.