A Universal Law for Interaction of 2D Materials with Cellular Membranes

Understanding the interaction of 2D materials including graphene-based nano-sheets, boron ni- tride and MoS2 with biological systems is a growing topic of interest to many applications such as biosensors, drug delivery, gene therapy and nanotoxicity. In this paper, we show that the interaction of 2D materials with cellular membranes at its early stage of approaching is dominantly controlled by entropic factors. Recent experiments indicate that graphene sheets, depending on their size, can either undergo a near-orthogonal cutting or a parallel attachment mode of interaction with cell membranes. Here we perform a theoretical statistical mechanics analysis as well as coarse-grained molecular dynamics simulations to characterize the entropic energy barrier for these modes of inter- actions. Our results indicate that micro-sized graphene sheets strongly prefer to approach cellular membranes through their sharp corners. In contrast, nano-sized sheets are likely to adhere to the membranesurface,insteadofpiercingthroughtheirsharpcorners.