Angiopep-2修饰载神经毒素介孔二氧化硅脂质囊纳米粒的制备及其体内外评价

Preparation and in Vitro/in Vivo Evaluation of Angiopep-2 Modifying Neurotoxin Loaded PhospholipidFunctionalized Mesoporous Silica Nanoparticles

目的制备Angiopep-2(ANG)修饰的载神经毒素(neurotoxin,NT)介孔二氧化硅脂质囊纳米粒(mesoporous silica nanoparticles,MSN)(ANG-LP-MSN-NT),并进行体内外评价。方法利用改进的Stober法制备介孔二氧化硅纳米粒,然后运用薄膜水化法制备ANG-LP-MSN-NT。考察其形态、粒径、Zeta电位、载药量和包封率;通过小角粉末衍射、氮气吸-脱附法等技术对其进行表征;透析袋法考察其体外释药特性;热板法和醋酸扭体法考察其镇痛效果。结果制备的MSN比表面积为557 m^2?g^(-1),孔径和孔容积(V_p)分别为2.94 nm和0.58 cm^3?g^(-1)。ANG-LP-MSN-NT分布均一,无团聚现象,粒径为(123.37±3.76)nm(PDI 0.20±0.02),Zeta电位为(-16.57±1.59)m V,载药量与包封率分别为(10.75±0.54)%与(91.82±3.12)%。ANG-LP-MSN-NT较MSN-NT体外突释降低,缓释特性明显;药效学实验结果表明ANG-LP-MSN-NT起效快、最大镇痛效应优于其他组别。结论ANG-LP-MSN-NT解决了二氧化硅易团聚、易突释的问题,且更有利于NT在脑部富集,发挥更好的镇痛效果,该纳米递药系统作为神经毒素载体在镇痛方面具有较好的应用前景。

OBJECTIVE To prepare and evaluate Angiopep-2（ANG）modifying neurotoxin（NT）loaded phospholipidfunctionalized mesoporous silica nanoparticles（MSN）（ANG-LP-MSN-NT）.METHODS MSN was synthesized by modified-Stober method.MSN-NT was developed by impregnation adsorption method.ANG-LP-MSN-NT was prepared by film hydration method.Laser particle size analyzer and transmission electron microscope were used to determine the particle size,Zeta potential and morphology.Small angle X-ray diffraction was used to determine the mesoporous structure;nitrogen adsorption method was used to calculate the surface area,pore diameter and pore volume.The drug release behavior of ANG-LP-MSN-NT was studied by dialysis method.Pharmacodynamics of ANG-LP-MSN-NT was studied by the hot-plate test and the acetic acid-writhing test.RESULTS The specific surface area,pore diameter and pore volume（Vp）of MSN were 557m2？g-1,2.94 nm and 0.58 cm3？g-1,respectively.The mean particle size and Zeta potential of ANG-LP-MSN-NT were（123.37±3.76）nm with PDI 0.20±0.02 and（-16.57±1.59）m V.The drug loading and entrapment efficiency of ANG-LP-MSN-NT were（10.75±0.54）%and（91.82±3.12）%.In vitro release,compared with MSN-NT,burst release of ANG-LP-MSN-NT was smaller and sustained release was more obvious.The results of pharmacodynamics experiment showed that the onset time and the maximum effect of ANG-LP-MSN-NT were better than other groups.CONCLUSION The successful preparation of ANG-LP-MSN-NT solves the problem of aggregation and burst release of MSN and low drug loading and easy leakage of liposomes.ANG-LP-MSN-NT has profit for NT enrichment in brain and a better analgesic effect.ANG-LP-MSN is a prospective drug delivery system for neurotoxin.