Membrane Insertion of MoS2 Nanosheets: Fresh vs. Aged

Abstract

Fresh two-dimensional (2D) molybdenum disulfide (MoS2) can absorb the hydrocarbon contamination from the ambient air and cause surface aging. Thus, understanding how the surface aging process of MoS2 affects the interaction with biomolecules is crucial for its applications in the biomedical field. Here, we employed atomistic molecular dynamics simulations to investigate the interactions of fresh and aged MoS2 nanosheets with POPE lipid membranes. Our results show that even though both the fresh and aged MoS2 nanosheets are capable of spontaneous insertion into the POPE bilayer membrane, the fresh MoS2 nanosheet displays significantly more robust interaction than the aged one. The potential mean force (PMF) calculations further confirm that the fresh MoS2 nanosheet is more energetically favorable than the aged one in penetrating into the POPE lipid membranes, with the former having ~17 kJ/mol stronger binding affinity than the later. This work provides a deeper understanding of the surface-aging-dependent interaction of MoS2 nanosheet with biomolecules, which might help the design of better MoS2-based nanodevices with appropriate surface properties.