George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
ACS Nano. 2012 Jan 24;6(1):212-9. doi: 10.1021/nn2043143. Epub 2011 Dec 23.
Using a mesoscale computational model, we probe the release of nanoparticles and linear macromolecules from hollow microgel capsules that swell and deswell in response to external stimuli. Our simulations reveal that responsive microcapsules can be effectively utilized for steady and pulsatile release of encapsulated solutes. Swollen gel capsules allow steady, diffusive release of nanoparticles and polymer chains, whereas gel deswelling causes burst-like discharge of solutes driven by an outward flow of the solvent enclosed within a shrinking capsule. We demonstrate that this hydrodynamic release can be regulated by introducing rigid microscopic rods in the capsule interior. Thus, our findings disclose an efficient approach for controlled release from stimuli-responsive microcarriers that could be useful for designing advanced drug delivery systems.
利用介观计算模型，我们探测了纳米颗粒和线性大分子从空心微凝胶胶囊中的释放，这些微凝胶胶囊会对外界刺激做出膨胀和收缩的响应。我们的模拟表明，响应性微胶囊可有效地用于包封溶质的稳定和脉动释放。膨胀的凝胶胶囊允许纳米颗粒和聚合物链的稳定扩散释放，而凝胶的收缩会导致溶剂的向外流动，从而引起溶质的突发式释放。我们证明，通过在胶囊内部引入刚性微棒，可以调节这种流体动力释放。因此，我们的研究结果揭示了一种从刺激响应性微载体中进行控制释放的有效方法，这对于设计先进的药物输送系统可能是有用的。
