Molecular dynamics simulation of cancer cell membrane perforated by shockwave induced bubble collapse

Abstract

It has been widely accepted that cancer cells are softer than their normal counterparts. This motivates us to propose a method to deliver efficiently therapeutic agents into cancer cells while normal cells are less affected. The basic ideal is to employ the water jet generated by collapse of bubble under shockwave to perforate pores in the cell membrane. Given a combination of shockwave and bubble parameters, the cancer membrane is more susceptible to bending, stretching and perforating than the normal membrane because bending modulus of the cancer cell membrane is smaller than that of the normal cell membrane. Therefore, therapeutic agent delivery into cancer cells is easier than in normal cells. Adopting two well-studied models of the normal and cancer membranes, we perform shockwave induced bubble collapse molecular dynamics simulations to investigate the difference in response of two membranes over a range of shockwave impulse 15-30 mPa.s and bubble diameter 4-10 nm. The simulation shows that the presence of bubble is essential for generating water jet which is required for perforation, otherwise pores are not formed. Given a set of shockwave impulse and bubble parameters, the pore area in the cancer membrane is always larger than that in the normal membrane. But too strong shockwave and/or too large bubble results in too fast disruption of membranes, and pore areas are similar between two membrane types. The closing time of the pore in the cancer membrane is slower than that in the normal membrane.

Fluorescence enhancement of organic dyes by femtosecond laser-induced cavitation bubbles for crystal imaging

“…Although the generation and rupture of cavitation bubbles will generate large energy, the bubble generation in this method is millimeters away from the sample crystals. Damage to the biosample, for example the opening of cell membranes, 36,37 requires the bubbles to be close to the cells. As for the experimental conditions where the fluorescence needs to be excited near the sample, the bubble evolution can be controlled by the flow jet reported in the time-resolved observation of bubble dynamics.…”