PFAS-induced modulation of vesicle diffusiophoresis

Abstract

Understanding how per- and polyfluoroalkyl substances (PFAS) partition into biological membranes and alter their properties is central for elucidating PFAS toxicity. Here, we experimentally investigate how the partitioning of anionic PFAS affects the surface charge of phospholipid vesicles and consequently, their electrokinetically driven vesicle motion, in particular diffusiophoresis. We find that PFAS partitioning enhances vesicle diffusiophoresis, consistent with a model combining the Nernst-Planck and Langmuir adsorption equations. Desorption experiments, together with quartz crystal microbalance with dissipation monitoring (QCM-D), further reveal that substantial lipid loss occurs during PFAS partitioning. We attribute this loss to lipophobic interactions between the fluorocarbon chains of PFAS and the alkyl chains of lipids. Our findings provide new mechanistic insights into how PFAS may disrupt biological systems.