Endothelial glycocalyx permeability for nanoscale solutes.

Endothelial glycocalyx plays multiple roles in the vascular system: it regulates vascular permeability, modulates the interactions between blood and endothelial cells and controls the shear stress produced by the blood flow. The defense it provides against nanoscale blood solutes such as viruses and nanoparticles is based on nonspecific interactions. Being a natural sieve, it also influences the delivery of medicines transported by the blood flow. In this work, using a computational study of the permeability of endothelial glycocalyx, we demonstrate that the mesh formed by glycan fibers forms an effective mechanical barrier against penetration by nanoscale solutes. We evaluate the characteristic energies and times for the penetration of solutes of various sizes through the glycocalyx and assess the role of different contributions to nanoparticle­glycocalyx interactions. The obtained results may help clarify glycocalyx dysfunction and design drug nanocarriers and other nanoparticle-based medical applications.