Ballistic impact response of lipid membranes. Issue 10 (21st February 2018)

• Record Type: Journal Article
• Authors: Zhang, Yao; Meng, Zhaoxu; Qin, Xin; Keten, Sinan
• Is Part Of: Nanoscale. Volume 10:Issue 10(2018)
• Page Start: 4761
• Page End: 4770
• Publication Date: 2018-02-21
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c7nr08879e
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : Nanoscale high-velocity projectiles carrying therapeutic agents can pursue distinct pathways upon impact with lipid membranes, which are characterized here to understand mechanisms of internalization. Abstract : Therapeutic agent loaded micro and nanoscale particles as high-velocity projectiles can penetrate cells and tissues, thereby serving as gene and drug delivery vehicles for direct and rapid internalization. Despite recent progress in developing micro/nanoscale ballistic tools, the underlying biophysics of how fast projectiles deform and penetrate cell membranes is still poorly understood. To understand the rate and size-dependent penetration processes, we present coarse-grained molecular dynamics simulations of the ballistic impact of spherical projectiles on lipid membranes. Our simulations reveal that upon impact, the projectile can pursue one of three distinct pathways. At low velocities below the critical penetration velocity, projectiles rebound off the surface. At intermediate velocities, penetration occurs after the projectile deforms the membrane into a tubular thread. At very high velocities, rapid penetration occurs through localized membrane deformation without tubulation. Membrane tension, projectile velocity and size govern which phenomenon occurs, owing to their positive correlation with the reaction force generated between the projectile and the membrane during impact. Two critical membrane tension values dictate the boundaries among the three pathways for a given system, due to the rate dependence of the stress generated in the membrane. Our findings provide broad physical insights into the ballistic impact response of soft viscous membranes and guide design strategies for drug delivery through lipid membranes using micro/nanoscale ballistic tools.