生物素化壳聚糖纳米粒的制备及其相关性质

制备了生物素化的壳聚糖纳米粒(biotinylated chitosan nanoparticles，Bio-CS-NP)并测定其相关性质，以此作为抗癌药物的载体。制备过程为：先用磺酸琥珀酰亚胺生物素与壳聚糖反应生成生物素化的壳聚糖(biotinylated chitosan，Bio-CS)，再采用氯化钠沉淀法制备Bio-CS-NP。采用试剂盒测定Bio-CS-NP表面配体连接密度，用透射电镜和激光粒度分析仪分别检测纳米粒的形态和粒径，并比较了人肝癌HepG2细胞对Bio-CS-NP和未经生物素修饰的壳聚糖纳米粒(chitosan nanoparticles，CS-NP)的摄取情况。结果显示，Bio-CS-NP表面配体连接密度为2.2 biotin CS；纳米粒形态为圆球形，表面光滑，平均粒径为296.8 nm，多分散指数为0.155；HepG2细胞对Bio-CS-NP的摄取能力显著高于CS-NP(P<0.05)。以上研究结果表明Bio-CS-NP有望成为一种新型的药物载体，用于抗癌药物对癌细胞的主动靶向。生物素的检测方法简便、可行。

Preparation and characterization of biotinylated chitosan nanoparticles

Biotinylated chitosan nanoparticles(Bio-CS-NP) were prepared for the active delivery to cancer cells and its characterization was investigated in this study.The preparation process included two steps.First,biotinylated chitosan(Bio-CS) was obtained through a reaction between sulfosuccinimidobiotin and chitosan(CS).Second,Bio-CS-NP were prepared by the precipitation of Bio-CS with sodium chloride solution.With a biotin reagent box,the conjugation densities of biotin on the surface of Bio-CS-NP were determined.The morphology and diameter of the nanoparticles were assayed by transmission electron microscope(TEM) and laser light scattering particle analyzer,respectively.The uptake of nanoparticles by human hepotacarcinoma HepG2 cells,for example,Bio-CS-NP and chitosan nanoparticles(CS-NP) without any modification,was quantitatively examined.The results indicated that the conjugation densities of biotin on the surface of Bio-CS-NP were 2.2 biotin CS.Bio-CS-NP were spherical,smooth on the surface.The average diameter was 296.8 nm.The polydispersion index was 0.155.The uptake of Bio-CS-NP by HepG2 cells was much higher than that of CS-NP(P<0.05).It demonstrated that Bio-CS-NP can be applied as a new vehicle to actively deliver anticancer drugs to tumor cells.The method for the determination of biotin was simple and practical.