敏感性聚电解质纳米粒子的制备及对5-FU的控制释放

以壳聚糖(CS)和海藻酸钠(SA)为原料,通过接枝共聚制备了壳聚糖接枝聚N-乙烯基吡烙烷酮(CSg-PVP)和海藻酸钠接枝聚N-乙烯基吡烙烷酮(SA-g-PVP),然后利用静电自组装得到了pH敏感性聚电解质纳米粒子,研究了纳米粒子对5-氟尿嘧啶的负载及释放性能的影响.傅立叶红外光谱验证了聚合物的结构.当CS-g-PVP与SA-g-PVP体积比为3∶7时,形成的纳米粒子结构最稳定.透射电镜表明纳米粒子具有较规则的球形结构,尺寸在30~50 nm左右.聚电解质纳米粒子对5-FU表现出较高的负载能力,环境pH值和离子强度等因素对5-FU的释放有影响.

Synthesis of Sensitive Polyelectrolyte Complex Nanoparticles and the Controlled Release of 5-FU

pH-sensitive polyelectrolyte complex nanoparticles assembled from chitosan-graft-poly （ 1-vinyl-2-pyrrolidone） （CS-g-PVP） and sodium alginate-graft-poly（1-vinyl-2-pyrrolidone） （SA-g-PVP） were prepared for entrapment and release of 5-fluorouracil （ 5-FU ） . The structure of polymers was determined by fourier-transformed infrared spectroscopy （ FTIR） . The highly aggregated nanoparticle was formed at the weight ratio of CS-g-PVP and SA-g-PVP is 3∶7 with a core formed from positively charged CS and negatively charged SA and a shell formed from hydrophilic PVP. The size and morphology of the nanoparticles was observed by transmis-sion electron microscopy （ TEM） . The dried particles gave the normally spheres with an average diameter of 30~50 nm. The CS-g-PVP/SA-g-PVP polyelectrolyte complex nanoparticles exhibited high drug loading content and encapsulation efficiency for 5-FU. Decreasing pH to weak acid or increasing ionic strength of nanoparticles solution,a sustained and controlled drug release was observed due to the deformation of nanoparticles.