PSU researcher Dr. Marilyn Rampersad Mackiewicz with one of her students.
Portland State University recently received $250,000 from the National Science Foundation for research that seeks to improve our understanding of silver nanoparticles. The award is part of a larger $500,000 grant split between PSU and Oregon State University (OSU), which are collaborating on the study.
Silver nanoparticles have unique properties that make them an appealing target material for use in applications including photovoltaics, biological and chemical sensors, antimicrobial coatings, antivirals, diagnostics, and drug-delivery platforms. Questions remain, however, about the stability and toxicity of these nanomaterials in vivo. These are difficult questions to answer, however, as silver nanoparticles undergo chemical processes resulting in surface oxidation and dispersion of silver ions that damage cells in living organisms. Consequently, there are gaps in our understanding of the human health and environmental impacts of the nanoparticles.
To fill some of these gaps, researchers at PSU and OSU will develop a portfolio of hybrid-lipid coated silver nanoparticles of various sizes and shapes that can control for the dispersion of silver ions. Their research will explore how factors such as the size, shape, and surface coating of silver nanoparticles affect nanoparticle stability, biological interactions, biouptake, and ecotoxicity.
PSU researcher Dr. Marilyn Rampersad Mackiewicz is a bioorganic and organometallic chemist and an expert in nanomaterials synthesis and characterization is a co-principal investigator on the study. Mackiewicz’s co-principal investigator is Dr. Stacey Harper, a nano-toxicologist at OSU.
From her lab at PSU, Mackiewicz and undergraduate student Henry Wu will design and synthesize the nanoparticles and identify features that lead to particle instability, which could result in toxicity. At OSU, Harper will study particle uptake and toxicity in zebrafish models and assess the potential ecotoxicity of the nanoparticles in a small-scale freshwater ecosystem in the lab.
“The results of this study will inform policymakers about the potential ecological and human health hazards of silver nanoparticle,” Mackiewicz said. “From there we can go on to develop safety protocols, exposure guidelines, and regulations that protect human and ecosystem health from products containing silver nanoparticles.”