Zhang Chi, Yan Kelu, Hu Chunyan, Zhao Yongliang, Chen Zhi, Zhu Xiaomin, Möller Martin
College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, 2999 North Renmin Road, Shanghai 201620, China.
J Mater Chem B. 2015 Feb 21;3(7):1261-1267. doi: 10.1039/c4tb01701c. Epub 2014 Dec 22.
In this work we report a fully aqueous and highly efficient method for the encapsulation of enzymes in silica nanocapsules during their formation process. In this approach, enzymes are first enclosed into unilamellar vesicles self-assembled by an amphiphilic precursor polymer - poly(ethylene glycol) substituted hyperbranched polyethoxysiloxane (PEG-PEOS) - in water. After subsequent condensation under basic conditions enzyme-loaded silica nanocapsules are obtained. Due to the significant volume shrinkage during the PEG-PEOS conversion, the encapsulation efficiency is very high, i.e. by adding only 5 wt% PEG-PEOS almost 50% of the enzyme from the solution is encapsulated. As compared with the free enzyme, the protease encapsulated by this means preserves almost 40% of its activity, exhibits significantly enhanced stability against the change of environmental conditions, and can be repeatedly regenerated without a significant activity loss.
在这项工作中，我们报道了一种在酶形成过程中将其封装到二氧化硅纳米胶囊中的完全水性且高效的方法。在这种方法中，酶首先被包裹在由两亲性前体聚合物——聚（乙二醇）取代的超支化聚乙氧基硅氧烷（PEG-PEOS）——在水中自组装形成的单层囊泡中。在碱性条件下随后缩合后，得到负载酶的二氧化硅纳米胶囊。由于PEG-PEOS转化过程中显著的体积收缩，封装效率非常高，即仅添加5 wt%的PEG-PEOS，溶液中几乎50%的酶被封装。与游离酶相比，通过这种方式封装的蛋白酶保留了其近40%的活性，对环境条件变化表现出显著增强的稳定性，并且可以反复再生而没有明显的活性损失。
