Encapsulation of water-insoluble drugs in poly(butyl cyanoacrylate) nanoparticles.

Hydrophobic drugs, loperamide and paclitaxel, were loaded in poly(butyl cyanoacrylate) nanoparticles by polymerization of n-butyl-2-cyanoacrylate in aqueous-organic media in the presence of a drug. The particles were stabilized by dextran 70,000 and poloxamer 188 or by 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-5000] sodium salt. It was shown that in the presence of dichloromethane, methanol or ethanol the encapsulation efficiency of loperamide in the nanoparticles reached 80%. Loading of paclitaxel was efficient only in the presence of the lipid. The organic solvents did not significantly influence the nanoparticle morphology or their physicochemical parameters. Thus produced poly(butyl cyanoacrylate) nanoparticles enabled delivery of loperamide across the blood-brain barrier, which was evidenced by the drug analgesic effect evaluated by the tail-flick test.