Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA.
Macromol Biosci. 2010 Feb 11;10(2):192-201. doi: 10.1002/mabi.200900229.
A new type of pH-responsive block copolymer nanoparticle has been synthesized and characterized. The amphiphilic diblock copolymer, PEG-b-PMYM, contains acid-labile ortho ester side-chains in the hydrophobic block and can self-assemble into micelle-like nanoparticles in water at neutral pH. Hydrolysis of the ortho ester side-chains follows a distinct exocyclic mechanism and shows pH-dependent kinetics, which triggers changes in nanoparticle size and morphology. The nanoparticles have been found to be non-toxic to cells in vitro. The ability to tune the size and morphology of biocompatible block copolymer nanoparticles by controlling the pH-sensitive side-chain hydrolysis represents a unique approach that may be exploited to improve the efficacy of nanometer-scale drug delivery.
已合成并表征了一种新型 pH 响应嵌段共聚物纳米粒子。两亲性嵌段共聚物 PEG-b-PMYM 在疏水性嵌段中含有酸不稳定的邻酯侧链，在中性 pH 下可自组装成胶束样纳米粒子。邻酯侧链的水解遵循明显的外消旋机制，并表现出 pH 依赖性动力学，这引发了纳米粒子尺寸和形态的变化。已发现这些纳米粒子在体外对细胞无毒。通过控制 pH 敏感侧链水解来调节生物相容嵌段共聚物纳米粒子的尺寸和形态的能力代表了一种独特的方法，可能被用于提高纳米级药物输送的疗效。
