PASSAGE OF PEPTIDES THROUGH THE BLOOD-BRAIN-BARRIER WITH COLLOIDAL POLYMER PARTICLES (NANOPARTICLES)

Transport of the hexapeptide dalargin across the blood-brain barrier w as accomplished using a nanoparticle formulation. The formulation cons isted of dalargin bound to poly(butyl cyanoacrylate) nanoparticles by sorption, coated with polysorbate 80. Intravenous injection of this fo rmulation to mice resulted in an analgesic effect. All controls, inclu ding a simple mixture of the three components (drugs, nanoparticles, a nd surfactant) mixed directly before i.v. injection, exhibited no effe ct. Analgesia was also prevented by pretreatment with naloxone. Fluore scent and electron microscopic studies indicated that the passage of t he particle-bound drug occurred by phagocytic uptake of the polysorbat e 80-coated nanoparticles by the brain blood vessel endothelial cells.