MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China.
Langmuir. 2011 Feb 15;27(4):1286-91. doi: 10.1021/la103758t. Epub 2010 Nov 2.
Single-component microcapsules were fabricated by the in situ reaction of ferrocenecarboxaldehyde (Fc-CHO) with poly(allylamine hydrochloride) (PAH) doped inside CaCO(3) microparticles, followed by core removal. The PAH-Fc microcapsules had very thick shells with remnant PAH-Fc inside, leading to a robust capsule structure that is less collapsed in the dry state. This single-component microcapsule is stabilized by the hydrophobic aggregation of Fc moieties and the protection of hydrophilic PAH backbones. Because of the excellent redox properties of Fc, the PAH-Fc microcapsules showed redox sensitivity to oxidation and reduction, as confirmed by UV-vis absorption spectroscopy and confocal laser scanning microscopy, resulting in reversible swelling and shrinking (11.7 vs 5.5 μm) in their size. Consequently, the permeability was also reversibly tuned, leading to the controlled loading and release of desired substances such as dextran.
单一组分微胶囊是通过原位反应制备的，反应物为二茂铁甲醛（Fc-CHO）与掺杂在碳酸钙微球内部的聚烯丙基氯化铵（PAH），随后去除微球的核。所得的 PAH-Fc 微胶囊具有非常厚的壳，内部残留有 PAH-Fc，这导致胶囊结构非常坚固，在干燥状态下不易坍塌。这种单一组分微胶囊是通过 Fc 部分的疏水性聚集和亲水 PAH 主链的保护来稳定的。由于 Fc 具有优异的氧化还原性能，PAH-Fc 微胶囊对氧化还原表现出敏感响应，这一点通过紫外-可见吸收光谱和共聚焦激光扫描显微镜得到了证实，导致其尺寸发生可逆的溶胀和收缩（11.7 与 5.5 μm）。因此，渗透性也可以进行可逆调节，从而实现对诸如葡聚糖等所需物质的控制加载和释放。
