Nanoparticle Endocytosis: The Membrane-Wrapping Model

Before a drug-carrying nanoparticle can act inside a cell, it first has to get in — and that entry is its own physics problem. This simulator models the moment a ligand-coated nanoparticle lands on a receptor-studded membrane: a real free-energy competition between the fixed bending cost of wrapping a sphere, a size-scaling adhesion gain from receptor–ligand bonds, and a neck line-tension barrier that must be crossed before the vesicle can scission free. Drag the nanoparticle radius, receptor density, membrane stiffness and line tension and watch the membrane actually deform around the particle in 3D, tracking live wrapping fraction and free energy, then see which endocytic route the outcome resembles — caveolae-mediated, clathrin-mediated, macropinocytosis, or no uptake at all when the energetics never turn favorable.