RESUMO
<p><b>OBJECTIVE</b>To investigate the absorption enhancen effect of borneol/mentholum eutectic mixture (BO/ME) on nasal-brain delivery of neurotoxin loaded nanoparticles.</p><p><b>METHOD</b>Using microdialysis sampling technique in awake freely-moving rats, the counter per minute (cpm) of dialysates in right PAG of NT-loaded nanoparticles with the BO/ME (BO/ME-NT-NP), radiolabeled with sodium 125I-Iodide, were measured in a gamma-counter for radioactivity. After converting cpm into corresponding concentrations of NT byin vivorecovery of microdialysis probes, the pharmacokinetic parameters were calculated.</p><p><b>RESULT</b>The BO/ME-NT-NP could be absorbed into the brain, much better to NT-NP and the nanoparticles with borneol or menthdlum only, and the pharmacokinetics accorded with the two-compartment model. The parameters tmax, cmax, AUC, t 1/2(beta) were 0.68 h, 27.32 ng x mL(-1), 132.68 ng x h x mL(-1), 3.1076 h.</p><p><b>CONCLUSION</b>With adding BO/ME as absorption enhancer, NT could be significantly increased in the brain with the help of nanopartilces as carriers, and the time to maximal concentration was short, the elimination process was prolonged.</p>