ABSTRACT
Objective: To prepare chitosan neurotoxin nanoparticles (CS-NT-NP) and study its effect on the permeability of blood brain barrier and the serum levels of S100β by intranasal administration. Methods: A formamide extraction-ultraviolet spectrophotometry method was employed to determine the concentration of Evans blue (EB) in brain by different routes of administration and preparations. Qualitative analysis of fluorescence intensity and distribution of EB in brain tissue was performed by fluorescence microscopy. The serum S100β protein concentration was determined by ELISA. Results: Compared with the control group and NT group, CS-NT-NP could significantly increase the content of EB in the brain with time-effect relation and reached the peak at 120 min (P < 0.01); Compared with muscle injection and ip injection, intranasal administration could significantly increase the content of EB and reached peak time quickly. The results were consistent with the experimental results of qualitative analysis of fluorescence intensity and distribution of EB in brain tissue by fluorescence microscopy and S100β protein in serum. It was consistent with the experimental results of S100β protein. Conclusion: CS-NT-NP by intranasal administration can significantly increase the permeability of BBB, and further increase the drug concentration in the brain, which is a good carrier of macromolecular drugs into the brain.