INFLUENCE OF THE TYPE OF SURFACTANT ON THE ANALGESIC EFFECTS INDUCED BY THE PEPTIDE DALARGIN AFTER ITS DELIVERY ACROSS THE BLOOD-BRAIN-BARRIER USING SURFACTANT-COATED NANOPARTICLES

The ability of 12 different surfactants, coated onto the surface of na noparticles, to facilitate the delivery of a nanoparticle-bound model drug, dalargin, was investigated. The leu-enkephalin analogue hexapept ide dalargin was bound to polybutylcyanoacrylate nanoparticles by sorp tion for 3 h. Different surfactants were then coated over these nanopa rticles and were injected intravenously into mice. Nociceptive analges ia was then measured by the tail-flick text 15, 30, 45 and 90 min afte r injection. Only nanoparticles that had been coated with polysorbate 20, 40, 60 and 80 yielded a significant effect. The highest effect was observed with polysorbate 80. Maximum effects were found after 15 min , at a dalargin dosage of 10 mg/kg, and after 45 min, with 7.5 mg/kg. (C) 1997 Elsevier Science B.V.