The Brain Delivering Study Of Polysorbate 80 Modified Neurotoxin Nanopar Ticles After Intranasal Administration

Objective To prepare polysorbate-80 modified neurotoxin loaded polybutylcyanoacrylate nanoparticle(P-80-NT-NP)and investigate their physicochemical property.The tissue distribution study was used to evaluate its brain targeting performance after intranasal administration.Analgesia experiments were used to evaluate the analgesia effects of Neurotoxin of different approaches and the antinociceptive activity of the P-80-NT-NP and NT-NP through intranasal administration respectively.In vivo imaging system was used to study its distribution in vivo after intranasal administration in order to provide reference for other preparation study of brain targeting.Methods 1.P-80-NT-NP were prepared by emulsion polymerization method with PBCA as a carrier material.The morphology of P-80-NT-NP was observed by transmission electron microscope;The mean particle size and Zeta potential were estimated by Laser particle size tester/Zeta potentiometer;The entrapment efficiency and drug loading were investigated by ultracentrifugation;2.The SD rats were randomly divided into two groups.The tissue distribution study was used to discuss the tissue distribution of P-80-NT-NP and NT-NP through intranasal administration respectively in plasma,brain,liver,heart,spleen,lung,kidney;3.The hot plate test and the formalin test were used to evaluate the analgesia effects of Neurotoxin of different approaches,and the antinociceptive activity of the P-80-NT-NP and NT-NP through intranasal administration respectively;4.In vivo imaging system was used to study its distribution in vivo after intranasal administration.Results 1.The morphology of P-80-NT-NP was spherical,the mean particle size,Zeta potential were(75.37 ± 1.09)nm,(-10.96±1.77)mV,respectively.The entrapment efficiency and drug loading of NT were(70.30±2.69)%and(0.161±0.04)%;2.Tissue distribution study indicated that the P-80-NT-NP and NT-NP group after intranasal administration could distribute quickly in plasma and different tissues,plasma,liver and brain tissue in the higher levels.Delivery after 90 min,the drug content of P-80-NT-NP nasal drug delivery in the plasma was higher than the NT-NP group,with significant difference(P<0.01);The drug content in brain of P-80-NT-NP group was higher than NT-NP group,drug content increased significantly(P<0.05);3.The hot plate test results showed that the pain threshold reached the peak of P-80-NT-NP after intranasal administration in 90min,was 69.92%;within 30-60min,after intramuscular injection of NT,the pain threshold was greatly increased,and reached the peak in 30min,the pain threshold was 63.44%;the pain threshold reached the peak of P-80-NT-NP after intraperitoneal administration in 90min,was 63.97%;the formalin test results showed that in the phase ?,comparison of P-80-NT-NP and NT,could significantly inhibit the mice licking foot(P<0.01),the inhibition rate was 52.32%.Comparison of NT-NP and NT with significant difference(P<0.05).The second phase,the group of NT-NP have no obvious analgesic action,but comparison of P-80-NT-NP and NT,there was significant difference(P<0.05);4.The mice in vivo imaging test showed that the NT-NP nasal drug delivery arrived quickly with circulatory system after the whole body,and metabolic rapidly.The P-80-NT-NP group got into the brain quickly and slow-release effect is obvious in the body,prolong half-life,brain targeting was obviously stronger than the NT-NP group.Conclusions 1.The P-80-NT-NP was prepared by emulsion polymerization method,the morphology of P-80-NT-NP was spherical,with good stability.And had the high drug encapsulation efficiency and drug loading,achieved the demand of Brain deliver medication;2.The establishment of the microplate method is simple,rapid and accurate.The P-80-NT-NP and NT-NP group after intranasal administration could distribute quickly in plasma and different tissues,plasma,liver and brain tissue in the higher levels.The NT-NP modified with P-80,BBB permeability enhancement,and it targeted to the brain tissue distribution to make drug content increased significantly,thus provided the experimental basis for brain targeting;3.The P-80-NT-NP after nasal drug delivery within a certain period time,its analgesic effect time,efficacy continued time and the pain threshold are all better than intramuscular injection and intraperitoneal injection.It is a good administration to alternative the injection delivery of polypeptide drugs.In addition,it is beneficial for drugs to get into the brain,obviously improve the analgesic effect;4.This experiment used successfully in mice in vivo imaging technology,and we can directly observe its distribution in vivo after intranasal administration of P-80-NT-NP.The NT-NP nasal drug delivery arrived quickly with circulatory system after the whole body,and metabolic rapidly.The P-80-NT-NP group got into the brain quickly and slow-release effect is obvious in the body,prolong half-life,brain targeting was obviously stronger than the NT-NP group.