It was reported that nanoparticles with polysorbate 80 (Tween 80, T-80) coating represented tools used for delivering drugs to brain.
Being bound to nanoparticles that were overcoated by T-80 later, was necessary for the loading to be delivered to brain.
It seemed that brain targeting of nanoparticles was concerned with the interaction between T-80 coating and brain micro-vessel endothelial cells.