Hannah Edens, “Comparing Gold Nanoparticle and Magnetite Nanoparticle Penetration into Platelet Rich Plasma Clots”
Mentors: Julie Oliver & Cammy Truong, Biological Sciences

We are investigating alternative treatments for patients with ischemic stroke that are unable to receive tissue plasminogen activator (tPA) due to bleeding risk. We proposed that targeting activated platelets rather than fibrin in occlusive thrombi for magnetically induced hyperthermia could provide treatment for ischemic stroke with minimal risk of bleeding. Since synthesizing gold-coated magnetite nanoparticles (FGN-cAu-Fe₃O₄) is not a robust procedure, previous work used the robust fibrinogen-conjugated gold nanoparticles (FGN-cAu₁₈) model to examine the nanoparticle penetration into clots. The goal of this research is to inspect whether FGN-cAu-Fe₃O₄ and FGN-cAu₁₈ of approximately the same diameter show differences in their ability to penetrate and concentrate in clots during labeling. We hypothesize that FGN-cAu-Fe₃O₄ will access the interior of platelet-rich plasma (PRP) clots to the same extent as FGN-cAu₁₈. To test that hypothesis, PRP was clotted in vitro using low and high thrombin concentrations, followed by labeling with either FGN-cAu₁₈ or FGN-cAu-Fe₃O₄. Frozen cross-sections were treated with silver enhancement and analyzed by light microscopy. As expected, FGN-cAu₁₈ and FGN-cAu-Fe₃O₄ produced several similar results. First, the degree of nanoparticle penetration and concentration inside PRP clots are consistent between both types of nanoparticles. Second, the extent of nanoparticle penetration was inversely related to the thrombin concentration, with high thrombin concentration resulting in reduced nanoparticle penetration. Third, more nanoparticles deposit at the clot periphery and their concentration is reduced at the center of clots. These results confirm that FGN-cAu₁₈ can be a representative model for FGN-cAu-Fe₃O₄ in term of studying the nanoparticle penetration into clots.