Nanoindentation of biomembrane by carbon nanotubes – MD simulation

A series of steered molecular dynamics simulations (SMD) has been performed to study the process of nanoindentation of phospholipid bilayer by single-walled carbon nanotubes. Two types of armchair nanotubes: open-ended and capped were taken into account. Simulations were performed at physiological temperature T = 310 K, with constant pulling velocity of carbon nanotube ranging from 2 m/s to 20 m/s. The force acting on nanotube during membrane penetration versus indentation depth and free energy changes (PMF) have been calculated. We show that carbon nanotube indentation does not permanently destroy the membrane structure and the capped nanotube is less invasive comparing to open-ended.