Chemistry Colloquium: Chayan Dutta

The Department of Chemistry in the College of Arts and Sciences is pleased to welcome Chayan Dutta, an assistant professor at Georgia State University.

Title: Understanding the Plastic Problem: One Nanoplastic at a Time

Abstract: Plastic nanoparticles (PNPs) have emerged as a significant concern due to their potential adverse impacts on biosystems. Their small size and high surface-to-volume ratio facilitate interactions with lipid membranes, leading to structural modifications and long-term accumulation within membranes, ultimately resulting in functional changes. Also, theoretical predictions suggest that PNPs can disrupt the secondary structure of proteins through partial or complete denaturation. Such irreversible changes in protein structures are detrimental to the function of the native proteins. Despite theoretical predictions, direct experimental evidence remains limited. My group’s current research is focused on understanding these nanoscale effects using various high-resolution optical microscopy and spectroscopy techniques. I will discuss our recent efforts to understand transport dynamics and interactions of PNPs with biomimetic lipid surfaces, including 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and ganglioside GM1-POPC membranes, using single-particle tracking (SPT) and super-resolution diffusion analysis (fcsSOFI). Our results show that charged PNPs exhibit salt-dependent transport behavior, with increased confinement in higher ionic environments. Cholesterol in membranes slows surface diffusion, and phase-separated domains in GM1-POPC membranes introduce diffusion heterogeneity. Additionally, we investigate PNP-peptide interactions using circular dichroism (CD) spectroscopy and single-molecule Förster resonance energy transfer (smFRET), revealing that PNPs induce structural alterations in peptides, affecting both α-helix and β-sheet conformations. These findings provide critical insights into the nanoscale interactions of PNPs with lipid membranes and proteins, highlighting their potential biological impacts.