Wrapping of Nano- and Microgels by Lipid-Bilayer Membranes

The wrapping of nano- and microparticles is a fundamentally important pathway for their cellular uptake and depends on the physicochemical properties of both particle and membrane. Polymeric gels are a versatile class of materials whose elastic properties can be tuned in a wide range from ultrasoft to hard by changing the density of cross-linkers. Using spring networks for the microgels and triangulated surfaces for the membranes, we study microgel wrapping with computer simulations. The interplay of microgel and membrane deformation is controlled by the competition between microgel elasticity and membrane bending rigidity. Compared with hard particles, the range of adhesion strengths for which partial-wrapped states are stable is enlarged. Volume and surface area of partial-wrapped microgels can be significantly reduced compared with those of free microgels. Understanding microgel wrapping can help us to design polymeric particles for biomedical applications, e.g., as membrane markers and targeted drug delivery vectors.