Chung Yong-Il, Tae Giyoong, Hong Yuk Soon
Department of Materials Science and Engineering, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712, Korea.
Biomaterials. 2006 Apr;27(12):2621-6. doi: 10.1016/j.biomaterials.2005.11.043. Epub 2005 Dec 19.
A new, facile method to prepare the heparin-functionalized PLGA nanoparticle (HEP-PLGA NP) for the controlled release of growth factors is developed. This system is composed of PLGA as a hydrophobic core, Pluronic F-127 as a hydrophilic surface layer, and heparin as the functional moiety. HEP-PLGA NPs were prepared by a solvent-diffusion method without chemical modification of the components. The entrapment of heparin molecules was confirmed by a negatively increased zeta potential value and the specific binding affinity to antithrombin III. The average diameter and the surface charge of the nanoparticles were ranged from 139+/-2 to 188+/-4 nm and from -26.0+/-1.1 to -44.1+/-1.3 mV by increasing the amount of heparin during the nanoparticle preparation. Accordingly, the amount of heparin on the nanoparticle increased from 0% to 4.7%. As a model in vitro release experiment, lysozyme was loaded into HEP-PLGA NPs, and a sustained release profile over 2 weeks was obtained with maintaining its bioactivity. The release of rhVEGF, one of the heparin-binding growth factors, showed a more sustained and prolonged profile than that of lysozyme over one month.
开发了一种制备用于生长因子控释的肝素功能化聚乳酸-羟基乙酸共聚物纳米颗粒（HEP-PLGA NP）的简便新方法。该体系由作为疏水核心的聚乳酸-羟基乙酸共聚物、作为亲水表面层的普朗尼克F-127以及作为功能部分的肝素组成。HEP-PLGA NPs通过溶剂扩散法制备，无需对各组分进行化学修饰。通过zeta电位值负向增加以及与抗凝血酶III的特异性结合亲和力证实了肝素分子的包封。在纳米颗粒制备过程中增加肝素量时，纳米颗粒的平均直径和表面电荷范围分别为139±2至188±4 nm以及-26.0±1.1至-44.1±1.3 mV。相应地，纳米颗粒上肝素的量从0%增加到4.7%。作为体外释放实验模型，将溶菌酶载入HEP-PLGA NPs，获得了持续2周的释放曲线，并保持了其生物活性。肝素结合生长因子之一的rhVEGF的释放在一个多月内显示出比溶菌酶更持续和延长的曲线。
