We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Exploring Nile Red staining as an analytical tool for surface-oxidized microplastics
Summary
Scientists evaluated Nile Red, a fluorescent dye commonly used to detect microplastics, and found it works differently depending on whether microplastics have been weathered by the environment. Surface oxidation from aging in the environment changes how well the dye sticks to plastics, which means current detection methods may be undercounting weathered microplastics in environmental samples.
Microplastics (MPs), defined as plastic particles smaller than 5 mm, have garnered considerable attention owing to their potential biological impact on human health. These particles exhibit a range of physicochemical properties, including size, shape, and surface oxidation. Nile Red is a prominent tool for detecting microplastics, enabling staining for dynamic analyses within biological systems. However, the efficacy of Nile Red staining for surface-oxidized MPs remains unclear. Therefore, we applied Nile Red dye to stain surface-oxidized polyethylene and polyvinyl chloride and observed that both materials were effectively stained, although the fluorescence intensity varied according to different hydrophobic dynamics. Imaging analysis revealed a correlation between the fluorescence intensity score and the degree of surface oxidation, as determined using the carbonyl index calculated from attenuated total reflection-Fourier transform infrared spectroscopy data. Collectively, these findings offer novel analytical approaches for investigating environmental MPs, enhancing our understanding of their behavior and impact.