CAS-MNP: Understanding the Interactions Between Small Molecules and Plastic Nanoparticles for Environmental Remediation and Sensing Using Nuclear Magnetic Resonance

Clemson University, Clemson SC

Investigators

Abstract

With support from the Environmental Chemical Sciences program of the Division of Chemistry and the Established Program to Stimulate Competitive Research (EPSCoR), Leah Casabianca and her team at Clemson University will carry out experiments aimed at understanding the fundamental nature of binding between nanoscale plastic particles and small molecule pollutants. Plastic pollution is a growing environmental concern, made worse by the increasing use of plastic during the coronavirus pandemic. Large plastic particles break down in the environment to eventually form plastic nanoparticles. These particles may have a variety of surface characteristics due to the variable conditions experienced by the plastics in polluted waterways. Plastic nanoparticles also have a large surface-to-volume ratio and can be porous, allowing them to easily sorb small molecule contaminants that may also be present in polluted waterways. If plastic nanoparticles are ingested by wildlife or humans, these toxic small molecules may leach out of the plastic and cause harm. As part of the project, Dr. Casabianca’s team will participate in summer camps sponsored by Clemson’s Programs for Educational Enrichment and Retention (PEER) and Women in Science and Engineering (WISE) programs and will also develop demonstrations for high-school students that relate chemistry to the problem of nanoscale plastic pollution. The project will make use of Saturation-Transfer Difference Nuclear Magnetic Resonance (STD-NMR) spectroscopy to test different types of plastics (polyethylene, polypropylene, and polyvinyl chloride) for their ability to bind different contaminants. Competition STD-NMR will be used to investigate how other substances present in polluted waterways influence sorption of potential contaminants. Beyond just binding constants, the atomic site-specific nature of NMR spectroscopy and detailed structural information that it can provide will be used to understand the driving forces that are responsible for binding. Finally, in this project, the Clemson team will endeavor to develop new NMR methods to answer some the next questions on the horizon of environmental remediation and sensing. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.