Researcher(s)
- Xavier Flaiz, Chemistry, University of Delaware
Faculty Mentor(s)
- Ariel Alperstein, Chemistry and Biochemistry, University of Delaware
Abstract
The continued use of plastic in manufacturing has led to the proliferation of microplastics (MPs) and nanoplastics (NPs) in the environment as well as numerous organs of the human body, including blood, liver, kidneys, intestines, lungs, and the brain. Current literature suggests that MPs and NPs have a toxic effect on a variety of human cell lines. Particle detection in complex biological matrices is a key component of research aiming to investigate MP and NP presence and localization within tissue samples. One method of particle detection is Raman spectroscopy, which gathers information on the chemical bonds in a sample from the way the sample scatters laser light. Unlike many commonly used techniques for detection, spatially resolved Raman spectroscopy is a non-destructive method of MP and NP detection that provides data simultaneously on particle morphology, chemical identity, and localization within the cell. Despite its advantages, the size limit of detectable plastics using Raman is conflicted in literature. Many reviews report that the technique is generally limited to micro-scale (≥1000nm) despite other authors having imaged particles on the nano-scale (<1000nm). In this study, lung cells were incubated with fluorescent polystyrene particles of various sizes, then scanned in three dimensions using Raman spectroscopy. Collected spectra were used to generate and analyze 3D images of polymer particles within cells. By comparing the number of particles detected using Raman to the number detected using fluorescence imaging, a size limit for detectable polystyrene particles was determined.