Translocation of polyarginines and conjugated nanoparticles across asymmetric membranes

Understanding how cell-penetrating peptides translocate across cell membranes is of great importance in biomedicine. In this paper, we study the interactions between polyarginines and asymmetric membranes by using coarse-grained molecular dynamics simulations. It is found that a peptide has the probability to penetrate through the membrane because of the transmembrane potential difference; however, it is difficult for a single peptide to spontaneously penetrate through the membrane while multiple peptides can translocate across membranes by pore-mediated processes. Further, we also provide insights into the transporting ability of polyarginines, and find that the peptide can transport hydrophobic as well as hydrophilic particles through membranes, where the translocation of a hydrophobic particle is easier than that of a hydrophilic one. The present study can help to better understand the interactions of the peptides with cell membranes and may give some new suggestions on the design of future nanomaterials for drug delivery.