透明质酸基普鲁兰糖载药微球制备与体内外评价

Preparation and evaluation of doxorubicin loaded hyaluronic acid-pullulan microspheres in vitro and in vivo

普鲁兰糖(Pu)和透明质酸(HA)天然高分子材料具备良好生物相容性,常用作药物载体,但此类天然高分子降解快,限制其作为药物的缓释功能载体的应用.本文拟采用自制抗酶降解的透明质酸接枝普鲁兰糖(HA-Pu)材料溶液为水相,液体石蜡为油相,Span 80为乳化剂,戊二醛为交联剂,利用乳化交联法制备HA-Pu微球(HA-Pu MPs).利用Box-Behnken Design(BBD)法,考察转速、油水比和HA-Pu质量浓度等3因素对微球粒径的影响,当选择670 r/min搅拌转速,5.6∶1(体积比)油水比和44.8 mg/mL HA-Pu的最佳制备条件,可获得形态圆整且平均粒径约为18μm的微球.样品红外图谱显示,制备微球成功交联.以阿霉素(DOX)为模型药,交联量戊二醛0.5 mol,最佳DOX与HA-Pu投料比为2∶10(质量比),获得载药量为5.02%(质量分数),包封率为33%的(载药微球)DOX-HA-Pu MPs.载药微球体外释药曲线拟合符合Ritger-Peppas方程.而对比大鼠尾静脉注射DOX药物和腹腔注射DOX-HA-Pu MPs,载药微球具备缓释功能.利用HA-Pu材料抗酶降解性质,采用乳化交联法制备HA-Pu MPs,方法简单易行,制备微球有望成为抗瘤药物的缓释载体.

The natural macromolecular materials of pullulan(Pu)and hyaluronic acid(HA)have good biocompatibility and are often used as drug carriers.However,the rapid degradation of these natural macromolecule limits their application as drug sustained-release functional carriers.In this paper,the self-made anti-enzymatic degradation material of hyaluronic acid grafted pullulan(HA-Pu)is used to prepare its microspheres.In this system,HA-Pu material solution is used as the water phase,liquid paraffin as the oil phase,the Span 80 as the emulsifier,and the glutaraldehyde as the crosslinking agent to prepare the HA-Pu MPs.Box-Behnken Design(BBD)method was used to investigate the effects of rotational speed,oil-water ratio and HA-Pu concentration on the particle size of HA-Pu microspheres.When the optimal formulation conditions was selected as 670 r/min stirring speed,5.6∶1(V/V,mL/mL)oil-water ratio and 4.48 g/mL HA-Pu,the microparticles had a smooth surface with about 18μm diameter.The infrared spectrum of the sample shows that the prepared microspheres are successfully crosslinked.By using doxorubicin(DOX)as a model drug,with the cross-linking amount of glutaraldehyde being 0.5 mol,and with the optimum drug loading mass ratio being 2∶10,DOX-HA-Pu MPs with 5%drug loading and 33%encapsulation efficiency were obtained.In vitro release curve of drug-loaded microspheres was consistent with the Ritger-Peppas equation.when DOX drugs were injected into tail vein of rats and DOX-HA-Pu MPs were injected intraperitoneally in rats,the drug-loaded microspheres have displayed a sustained-release function.In summary utilizing HA-Pu material anti-enzymatic degradation properties,HA-Pu MPs are prepared by emulsion cross-linking method which is simple and easy to operate.Therefore,the preparation of HA-Pu MPs is expected to be a sustained-release carrier of antineoplastic drugs.