Multifunctional conjugation of proteins on/into bio-nanoparticles prepared by amphiphilic poly(γ-glutamic acid)
Multifunctional conjugation of proteins on/into bio-nanoparticles prepared by amphiphilic poly(γ-glutamic acid)
复制标题
DOI：
10.1163/156856206777996871
复制
发表时间：
2006-01-01
影响因子：
3.6
通讯作者：
Akashi, Mitsuru
中科院分区：
文献类型：
--
作者：
Akagi, Takami;Kaneko, Tatsuo;Akashi, Mitsuru
本研究的重点是由两亲性聚（γ-谷氨酸）（γ-PGA）作为潜在的蛋白质载体的纳米粒子。采用水溶性碳二亚胺（WSC）将L-苯丙氨酸乙酯（L-PAE）接枝到γ-PGA上，合成了以γ-PGA为亲水主链、L-苯丙氨酸乙酯（L-PAE）为疏水链段的两亲性接枝共聚物。由于它们的两亲性，γ-PGA-接枝-L-PAE共聚物在水中形成单分散的纳米颗粒。由γ-PGA-接枝-L-PAE组成的纳米颗粒（γ-PGA纳米颗粒）的粒径为约200 nm，并显示出高度负的zeta电位。为了评价其作为多功能蛋白质载体的潜在应用，我们通过包封、共价固定或物理吸附的方法制备了包封蛋白质的γ-PGA纳米颗粒。为此目的，使用具有不同分子量和等电点（pI值）的11种不同蛋白质作为模型蛋白质。对于所有测试的蛋白质，观察到蛋白质包封到纳米颗粒中。共价固定或吸附到纳米颗粒上的蛋白质的量显示出不同的趋势，基于每种蛋白质的分子量和pI。带正电荷的蛋白质可以通过静电相互作用吸附到带负电荷的纳米颗粒上。此外，它被发现，酶封装的纳米粒子比表面固定的纳米粒子表现出更高的酶活性。这些结果表明，酶包埋纳米粒子的酶活性显着影响的连接方法，和封装是最佳的方法，蛋白质和纳米粒子的连接。预计γ-PGA纳米颗粒作为多功能载体在药物和生物医学应用中具有巨大的潜力，例如药物和疫苗递送系统。
The present study focuses on nanoparticles composed of amphiphilic poly(gamma-glutamic acid) (gamma-PGA) as potential protein carriers. Amphiphilic graft co-polymers composed of gamma-PGA as the hydrophilic backbone and L-phenylalanine ethylester (L-PAE) as the hydrophobic segment were synthesized by grafting L-PAE to gamma-PGA using water-soluble carbodiimide (WSC). Due to their amphiphilic properties, the gamma-PGA-graft-L-PAE co-polymer formed monodispersed nanoparticles in water. The particle size of the nanoparticles composed of gamma-PGA-graft-L-PAE (gamma-PGA nanoparticles) was about 200 nm and showed a highly negative zeta potential. To evaluate their potential applications as multifunctional protein carrier, we prepared protein-entrapped gamma-PGA nanoparticles by encapsulation, covalent immobilization or physical adsorption methods. For this purpose, 11 different proteins with various molecular weights and isoelectric points (pI values) were used as model proteins. The encapsulation of the protein into the nanoparticles was observed for all tested proteins. The amount of protein covalently immobilized or adsorbed onto the nanoparticles showed different tends based on the molecular weight and pI of each protein. Positively charged proteins could be adsorbed onto the negatively charged nanoparticles by electrostatic interaction. Moreover, it was found that enzyme-encapsulated nanoparticles showed higher enzymatic activity than surface-immobilized nanoparticles. These results indicated that the enzymatic activity of the enzyme-entrapped nanoparticles was significantly affected by the conjugation method, and that encapsulation was the optimal method for the conjugation of proteins and nanoparticles. It is expected that the gamma-PGA nanoparticle will have great potential as multifunctional carriers in pharmaceutical and biomedical applications, such as drug and vaccine delivery systems.