Biophysics of the specific adhesion of nano-sized particles to cell membranes
Nano-sized particles such as a virus or an affinity ligand coated nanocarrier gain entry into a cell by first strongly adhering to the target cell membrane. The adhesion proceeds through multivalent interactions of ligands on the particle surface with their corresponding cell surface receptors. Such binding processes are ubiquitous in cell biology and their study may help in furthering our understanding of cellular adhesion. In this talk, I will present a multiscale computational framework that accounts for a variety of chemical and physical phenomena that govern the binding efficacy of the particles. I will demonstrate how the enthalpy of binding together with the loss in the configurational entropies sets an upper limit on the number of simultaneous receptor-ligand bonds. I will also show that the surface topography of the cell membrane alters this upper limit, and show comparisons of our model predictions with in vivo experimental results for five different organs in mouse.