Australian Institute for Bioengineering and Nanotechnology, The University of Queensland , St. Lucia, QLD 4072, Australia.
School of Chemical Engineering, The University of Queensland , St. Lucia, QLD 4072, Australia.
Langmuir. 2017 Jun 13;33(23):5777-5785. doi: 10.1021/acs.langmuir.7b00590. Epub 2017 May 30.
Silica nanocapsules have attracted tremendous interest for encapsulation, protection, and controlled release of various cargoes due to their unique hierarchical core-shell structure. However, it remains challenging to synthesize silica nanocapsules having high cargo-loading capacity and cargo-protection capability without compromising process simplicity and biocompatibility properties. Here, we synthesized oil-core silica-shell nanocapsules under environmentally friendly conditions by a novel emulsion and biomimetic dual-templating approach using a dual-functional protein, in lieu of petrochemical surfactants, thus avoiding the necessities for the removal of toxic components. A light- and pH-sensitive compound can be facilely encapsulated in the silica nanocapsules with the encapsulation efficiency of nearly 100%. Release of the encapsulated active from the nanocapsules was not shown an indication of undesired burst release. Instead, the release can be tuned by controlling the silica-shell thicknesses (i.e., 40 and 77 nm from which the cargo released at 42.0 and 31.3% of the initial amount after 32 days, respectively). The release kinetics were fitted well to the Higuchi model, enabling the possibility of the prediction of release kinetics as a function of shell thickness, thus achieving design-for-purpose silica nanocapsules. Furthermore, the nanocapsules showed excellent alkaline- and sunlight-shielding protective efficacies, which resulted in significantly prolonged half-life of the sensitive cargo. Our biomimetic silica nanocapsules provide a nanocarrier platform for applications that demand process scalability, sustainability, and biocompatibility coupled with unique cargo-protection and controlled-release properties.
由于具有独特的分级核壳结构，硅纳米胶囊在封装、保护和控制各种货物的释放方面引起了极大的兴趣。然而，在不损害工艺简单性和生物相容性的前提下，合成具有高载药量和货物保护能力的硅纳米胶囊仍然具有挑战性。在这里，我们通过一种新颖的乳液和仿生双重模板方法，使用一种双功能蛋白质，在环保条件下合成了油芯硅壳纳米胶囊，而不是使用石化表面活性剂，从而避免了去除有毒成分的必要性。可以将光和 pH 敏感的化合物轻易地封装在硅纳米胶囊中，封装效率接近 100%。从纳米胶囊中释放封装的活性物质没有显示出不需要的突释释放迹象。相反，可以通过控制硅壳厚度来调节释放（例如，厚度分别为 40nm 和 77nm，32 天后初始量的 42.0%和 31.3%释放）。释放动力学与 Higuchi 模型拟合良好，使根据壳厚度预测释放动力学的可能性成为可能，从而实现了有目的设计的硅纳米胶囊。此外，纳米胶囊表现出优异的耐碱性和遮光保护效果，显著延长了敏感货物的半衰期。我们的仿生硅纳米胶囊为需要工艺可扩展性、可持续性和生物相容性的应用提供了纳米载体平台，同时具有独特的货物保护和控制释放性能。
