Laboratory of Mesoscopic Chemistry and Department of Polymer Science & Engineering, College of Chemistry & Chemical Engineering, and Jiangsu Provincial Laboratory for Nanotechnology, Nanjing University, Nanjing 210093, People's Republic of China.
ACS Appl Mater Interfaces. 2010 Dec;2(12):3532-8. doi: 10.1021/am100709d. Epub 2010 Nov 16.
Poly(acrylic acid) (PAA) nanogels with a hollow core-porous shell structure were prepared by the direct polymerization of an acrylic acid monomer in the presence of hydroxypropylcellulose (HPC) and a cross-linking agent, N,N-methylenebisacrylamide, followed by removal of HPC from the generated HPC-PAA nanoparticles in a basic environment. The properties of PAA nanogel were characterized by dynamic light scattering, FT-IR, transmission electron microscopy, and atomic force microscopy. It is found that the nanogels have a hollow core-porous shell structure. Protein, bovine serum albumin (BSA), and an antitumor agent, doxorubicin hydrochloride, were used as model drugs to investigate their loading abilities as versatile drug-delivery vehicles. The nanogel exhibits surprisingly high loading ability to both protein and small molecular drugs. For example, the maximum BSA loading capacity of PAA nanogel can reach as high as 800% (i.e., 1 mg of nanogel can load about 8.0 mg of BSA). This high loading capacity may be related with the hollow core-porous shell structure of PAA nanogels. PAA nanogels have also shown sustained drug release properties and can cross biological barriers to deliver loaded cargo inside cells. Considering the high stability of the materials, simple and mild preparation procedure, high loading capacity, sustained-release property, and ability to protect biological agents from denaturation, PAA nanogels should be promising drug-delivery carriers for drug-delivery systems.
聚（丙烯酸）（PAA）纳米凝胶具有中空核-多孔壳结构，通过在羟丙基纤维素（HPC）和交联剂 N，N-亚甲基双丙烯酰胺存在下直接聚合丙烯酸单体制备，然后在碱性环境中从生成的 HPC-PAA 纳米颗粒中除去 HPC。通过动态光散射、FT-IR、透射电子显微镜和原子力显微镜对 PAA 纳米凝胶的性质进行了表征。结果发现纳米凝胶具有中空核-多孔壳结构。以蛋白质、牛血清白蛋白（BSA）和抗肿瘤药物盐酸阿霉素为模型药物，考察了其作为多功能药物载体的载药能力。纳米凝胶对蛋白质和小分子药物表现出令人惊讶的高载药能力。例如，PAA 纳米凝胶的最大 BSA 载药能力高达 800%（即 1mg 纳米凝胶可负载约 8.0mg BSA）。这种高载药能力可能与 PAA 纳米凝胶的中空核-多孔壳结构有关。PAA 纳米凝胶还表现出持续的药物释放特性，并且可以穿越生物屏障将负载的货物递送到细胞内部。考虑到材料的高稳定性、简单温和的制备程序、高载药能力、持续释放性能以及保护生物制剂免于变性的能力，PAA 纳米凝胶应该是药物输送系统中很有前途的药物载体。
