Abstract:ObjectiveTo prepare neurotoxin-I(NT-I)polybutylcyanoacrylate (PBCA) nanoparticles(NP) coated by polysorbate-80 and conduct its pharmacokinetic study in brain after intranasal administration in rats.MethodsNT-I Nanoparticles were prepared by emulsion polymerization method with PBCA as nanoparticle material. The pharmacokinetics in brain of NT-I nanoparticles coated or uncoated by polysorbate-80 after nasal application was characterized using brain microdialysis sampling technique.Results The concentration-time curve of NT-I nanoparticles coated and uncoated polysorbate-80 after intranasal administration in rats accorded with the two-compartment model. The pharmacokinetic parameters of tmax were (71. 018±7.641) and (55. 830±6. 072) min; Cmax were(117.189±10.036 ) and(52.277±6.217 )ng/mL, and AUC0→∞ were (22 836. 633±51.052) and (12786.934±30.723 )ng·min·mL-1,respectively.ConclusionPolysorbate-80 coating of PBCA nanoparticles could extend the time to peak of NT-I administered intranasally and significantly improve the NI-I concentration level in brain.