A facile strategy for efficient and continuous fabrication of monodisperse gas-core microcapsules with controllable sizes and excellent ultrasound-induced burst performances is developed based on droplet microfluidics and interfacial polymerization. Monodisperse gas-in-oil-in-water (G/O/W) double emulsion droplets with a gas core and monomer-contained oil layer are fabricated in the upstream of a microfluidic device as templates, and then water-soluble monomers are added into the aqueous continuous phase in the downstream to initiate rapid interfacial polymerization at the O/W interfaces to prepare monodisperse gas-in-oil-in-solid (G/O/S) microcapsules with gas cores. The sizes of both microbubbles and G/O/W droplet templates can be precisely controlled by adjusting the gas supply pressure and the fluid flow rates. Due to the very thin shells of G/O/S microcapsules fabricated via interfacial polymerization, the sizes of the resultant G/O/S microcapsules are almost the same as those of the G/O/W droplet templates, and the microcapsules exhibit excellent deformable properties and ultrasound-induced burst performances. The proposed strategy provides a facile and efficient route for controllably and continuously fabricating monodisperse microcapsules with gas cores, which are highly desired for biomedical applications.

中文翻译：

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气芯单分散微胶囊的微流控制备


基于液滴微流控和界面聚合，开发了一种高效、连续制造具有可控尺寸和优异的超声诱导爆裂性能的单分散气芯微胶囊的简便策略。在微流控装置的上游制备具有气核和含有单体的油层的单分散水包气包油（G/O/W）双乳液液滴作为模板，然后添加水溶性单体进入下游的水连续相，在O/W界面引发快速界面聚合，制备具有气核的单分散气包油包固（G/O/S）微胶囊。通过调节供气压力和流体流速，可以精确控制微泡和 G/O/W 液滴模板的尺寸。由于通过界面聚合制备的G/O/S微胶囊的壳非常薄，所得G/O/S微胶囊的尺寸几乎与G/O/W液滴模板的尺寸相同，并且微胶囊表现出优异的性能。可变形特性和超声波诱发的爆裂性能。所提出的策略为可控地、连续地制造具有气体核心的单分散微胶囊提供了一种简便有效的途径，这对于生物医学应用来说是非常需要的。