EAGER: NanoEHS Critical Needs - Determining Surface Composition in Biological Media and the Roles of Core Composition and Very Small Particles

University Of Iowa, Iowa City IA

Investigators

Abstract

Abstract CBET - 1424502 Vicki H. Grassian Overview: The challenges in understanding the environmental health and safety of nanomaterials (NanoEHS)are many but several fundamental issues in particular remain critical from a scientific perspective. In fact, it has become apparent that progress will be limited without studies to address these issues. Intellectual Merit: This EAGER proposal will address several critical needs in a concentrated program with specific objectives, hypotheses and goals. These critical areas include: 1. The nature of the surface of nanomaterials in biological media 2. The role of the core in surface functionalized nanoparticles 3. The unique behavior imparted to very small nanoparticles that is not just due to physical size but instead due to quantum and other intrinsic size dependent electronic effects. A series of targeted experiments are proposed to address these needs. These experiments are feasible and will provide the necessary results to define a framework to address the issues discussed in this proposal. In these experiments, nanoparticles will be covered using different surface functionalities including proteins. We will conduct these studies in different media relevant to understanding the toxicity of these particles, i.e. several simulated biological media of different pH to reflect both stomach and lung fluids. Furthermore, we can quantify the amount of dissolution and ROS production in each of these and as a function of particle size, within a size range where quantum confinement is important and outside of that size range where bulk properties of electronic state structure, e.g. the band gap, are relevant. Broader Impacts: There are several broader impacts and translational aspects of the proposed research. First, the proposed studies are designed to gain better insight into the environmental and health impacts of nanomaterials. These studies will contribute to the growing database on the potential environmental and health implications of nanoscience and nanotechnology. This society relevant research is designed to address potential environmental problems for the nanotechnology industry. Therefore overall it has the potential to provide for the greater good of the public and consumers. The proposed activities provide an opportunity to train students in a highly interdisciplinary research area that involves environmental science and engineering, chemistry, nanoscience, colloid and surface chemistry. The PI has a track record of successfully mentoring students at all levels from high school to postdoctoral associates and visiting research scientists and will continue this effort to mentor the next generation of scientists and engineers. Many of the students are from underrepresented groups in science and engineering including a large percentage of women (more than 60%) and minorities including students on free and reduced lunch programs and typically more diverse student populations. Funds from this NSF grant will be used to train graduate and undergraduate students to better engage these elementary students as well as the public in science and engineering.