| AVS 58th Annual International Symposium and Exhibition | |
| Biomaterial Interfaces Division | Wednesday Sessions |
| Session BI+AS+NS+SS-WeA |
| Session: | Functionalization and Characterization of Nanostructures |
| Presenter: | Christopher Szakal, National Institute of Standards and Technology |
| Authors: | C. Szakal, National Institute of Standards and Technology J. McCarthy, National Institute of Standards and Technology K. Louis, University of Wisconsin-Madison R.J. Hamers, University of Wisconsin-Madison R.D. Holbrook, National Institute of Standards and Technology |
| Correspondent: | Click to Email |
The environmental toxicity of engineered nanoparticles (ENPs) is of increasing importance as these materials become more widely used in manufacturing processes and consumer products. Nanoparticles have extremely high surface-to-volume ratios, which makes the surfaces more critical than their corresponding bulk materials in terms of reactivity, aggregation, and toxicity to various life forms. Therefore, it is critical that we develop methods to distinguish small chemical changes on nanoparticle surfaces in order to understand how these materials will interact outside of controlled laboratories. Conventional approaches of nanoparticle characterization have focused on high resolution morphological imaging (TEM, SEM) and physical property measurements such as surface charge. However, chemical information is generally only inferred from these materials with most current methods. If it is possible to obtain both elemental and molecular information from ENP surfaces, we may be able to determine the eventual fate of ENPs in the environment.
We have developed a comprehensive approach for studying the surface chemistry of ENPs, including 1) preparation of ENPs to controllably study desired variables, 2) development of methods such as time-of-flight secondary ion mass spectrometry (ToF-SIMS) and environmental scanning electron microscopy (ESEM) to probe small changes in ENP surface chemistry and/or aggregation, and 3) development of methods to improve the speed and reproducibility of ENP aggregation for batch studies. These approaches will be utilized as the basis of future toxicity studies of selected ecosystems.