Tetraethylene glycol coating of gold nanoparticles limits inflammatory response in mice. (2015)

Undergraduates: Julian Willett, Oliver Smithies

Faculty Advisor: Oliver Smithies
Department: Biology

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In recent years, nanoparticles have become more frequently used for medical treatment via drug delivery; however, there remain issues regarding their safety. Previous studies have found that in mice, gold nanoparticles coated with polyethylene glycol (PEG) are stable in blood, but they induce an inflammatory response, liver damage, and kidney damage upon administration via intraperitoneal injection. In this study, I synthesized gold nanoparticles and coated them with tetraethylene glycol (TEG) to determine if this smaller polymer caused similar effects to PEG or if the effects were bypassed. I performed retro-orbital injections into male mice with a solution of either saline, particles our lab knows to be fairly inert in mice, or TEG coated nanoparticles. I collected whole blood prior to injection, at two minutes, thirty minutes, and sixty minutes to submit for complete blood cell count. It was found that injection of nanoparticles, whether coated with TEG or the previously determined inert coating, caused a net decrease in white blood cell count, suggesting decreased inflammatory response. In addition, TEG coated nanoparticles appeared to trigger rapid and significant platelet removal or destruction compared to both controls. This suggests TEG coated particles bypass the inflammatory response, although this may be due to interaction with platelets. Thus, further research into TEG coated particles is needed before they can be considered viable delivery agents.