In drug delivery systems, PEG is often used to modify the surface of nanoparticles to create PEGylated nanoparticles. This modification can prolong the circulation time of the drug in the bloodstream by reducing opsonization and subsequent clearance by the reticuloendothelial system (RES). As a result, PEGylated nanoparticles can enhance the efficacy and reduce the toxicity of the therapeutic agents they carry.
