Objective The purpose of this paper is to prepare neurotoxin nanoparticles(NT-NPs), and investigate their physicochemical properties and release behavior in vitro and tissue distribution after intranasal(i.n.) administration. Method The NT-NPs were prepared by a modified double emulsion solvent evaporation method with polylactic acid(PLA) as carrier material and bornel/menthol eutectic mixture(BMEM) as absorption enhancer. The transmission electron microscope(TEM) and Zeta sizer instrument were utilized to ...