An efficient approach to study membrane nano-inclusions: From the complex biological world to a simple representation

Abstract

Membrane nano-inclusions (NIs) are of great interest in biophysics, materials science, nanotechnology, and medicine. We hypothesized that the NIs within a biological membrane bilayer interactviaa simple and efficient interaction potential, inspired by previous experimental and theoretical work. This interaction implicitly treats the membrane lipids but takes into account its effect on the NIs micro-arrangement. Thus, the study of the NIs is simplified to a two-dimensional colloidal system with implicit solvent. We calculated the structural properties from Molecular Dynamics simulations (MD), and we developed a Scaling Theory to discuss their behavior. We determined the thermal properties through potential energy per NI and pressure, and we discussed their variation as a function of the NIs number density. We performed a detailed study of the NIs dynamics using two approaches, MD simulations, and Dynamics Theory. We identified two characteristic values of number density, namely a critical number densitync= 3.67 × 10−3Å−2corresponded to the apparition of chain-like structures along with the liquid dispersed structure and the gelation number densityng= 8.40 × 10−3Å−2corresponded to the jamming state. We showed that the aggregation structure of NIs is of fractal dimensiondF< 2. Also, we identified three diffusion regimes of membrane NIs, namely, normal forn