Evaluation of Coated Gold Nanorods on Zebrafish Embryos

Gold nanoparticle’s utilization of targeting, imaging, and therapeutic mediums has increased dramatically in the last decade. Gold nanorods are frequently created following a seed-mediated approach whereby gold salts are catalyzed by the addition of small gold spheres (seeds) in the vicinity of a weak reducing agent and the growth directing surfactant cetyltrimethylammonium bromide (CTAB). Currently, interest in the utilization of gold nanomaterials has increased dramatically due to their potential to be used as therapeutic agents that address a wide variety of medical applications including vaccine development, cancer treatments, and pathogen annihilation. On the other hand, the critical toxicities of these materials have not been extensively researched and will continue to be a concern. Due to the similar toxicity model of human homology, zebrafish provide an appropriate model system to study the impacts of toxicity. The overall toxicity was evaluated based on embryo morbidity and observed abnormalities and deformities. Gold nanorods coated with the charged polyelectrolytes or CTAB alone showed significantly more toxicity than those coated with PEG. Additionally is has been demonstrated that we can selectively kill zebrafish which have been injected with gold nanorods while leaving those in the absence of the nanorods unharmed under near-infrared (NIR) irradiation. Current experiments include transplanting cells from one zebrafish that contains nanorods into a second zebrafish that does not. Samples are subsequently irradiated under NIR irradiation in an effort to selectively kill only those cells containing the gold nanorods as assessed via a LIVE/DEAD stain. These experiments are ongoing