The Cooperative Effect Analysis when Nanoparticles Enter a Biological Cell

Abstract

The nanoparticle (NP) is one of the most used nanostructures in biomedicine. The Np–biomembrane interface plays an important role in delivering NPs into a living biological cell. While most researchers focus on the interaction between a single Np and a cell membrane, we pay attention to the NP–biomembrane interaction when a cluster of NPs are put into a biological cell together, and analyze the cooperative effect of these NPs. We find that the NPs would not enter the cell individually, but have a trend to form an aggregation to reduce the repel force from the cell membrane. The dissipative particle dynamics simulation shows that the NP aggregation may have three interactive states with the membrane: adhere on the surface of the cell, uptaken by the membrane and enter the cell. We propose to use catalytic (CA) particles which are not sensitive to the membrane to reduce the driving force required in NP delivery. Energy analysis demonstrates that the introduced (CA) particles can decrease the free energy gap between the inside and the outside of the membrane, and increase the success rate of NPs entering the cell.