Lysosomal Membrane Permeabilization by Nanoparticles

One of the best-characterized mechanisms of nanoparticle toxicity is the "Trojan horse" effect: nanoparticles taken up by endocytosis end up trapped inside lysosomes, where the acidic lumen accelerates their dissolution and their surface chemistry progressively damages the surrounding phospholipid membrane. This simulator renders that process in 3D — nanoparticles diffuse inside a lysosome under Brownian motion scaled to the Stokes–Einstein relation, accumulate membrane damage as a function of dose, particle size, surface reactivity and dissolution rate, and once damage crosses a rupture threshold the membrane stochastically nucleates pores that release cathepsin enzymes into the cytosol — the step that experimentally triggers cathepsin-dependent apoptosis. Live readouts track membrane integrity, cumulative pore events, cathepsin release and the diffusion coefficient implied by the current particle size.