Queensland Micro- and Nanotechnology Centre, Griffith University, 170 Kessels Road, QLD, 4111, Nathan, Australia.
School of Engineering and Built Environment, Griffith University, QLD, 4111, Nathan, Australia.
Biomed Microdevices. 2022 Nov 10;24(4):40. doi: 10.1007/s10544-022-00637-9.
Core-shell microparticles containing an aqueous core have demonstrated their value for microencapsulation and drug delivery systems. The most important step in generating these uniquely structured microparticles is the formation of droplets and double emulsion. The droplet generator must meet the performance and reliability requirements, including accurate size control with tunability and monodispersity. Herein, we present a facile technique to generate surfactant-free core-shell droplets with an aqueous core in a microfluidic device. We demonstrate that the geometry of the core-shell droplets can be precisely adjusted by the flow rates of the droplet components. As the shell is polymerized after the formation of the core-shell droplets, the resulting solid microparticles ensure the encapsulation of the aqueous core and prevent undesired release. We then study experimentally and theoretically the behaviour of resultant microparticles under heating and compression. The microparticles demonstrate excellent stability under both thermal and mechanical loads. We show that the rupture force can be quantitatively predicted from the shell thickness relative to the outer shell radius. Experimental results and theoretical predictions confirm that the rupture force scales directly with the shell thickness.
含有水核的核壳微球在微封装和药物输送系统中表现出了其价值。生成这些具有独特结构的微球的最重要步骤是液滴和双重乳液的形成。液滴发生器必须满足性能和可靠性要求，包括具有可调性和单分散性的精确尺寸控制。在此，我们在微流控装置中提出了一种简便的技术，可生成无表面活性剂的具有水核的核壳液滴。我们证明，通过控制液滴各组分的流速可以精确调整核壳液滴的几何形状。由于在形成核壳液滴后聚合壳，因此所得的固体微球确保了水核的封装并防止了不期望的释放。然后，我们实验和理论研究了加热和压缩下所得微球的行为。微球在热和机械负荷下均表现出极好的稳定性。我们表明，可以从外壳厚度相对于外壳半径的关系来定量预测破裂力。实验结果和理论预测证实，破裂力与壳厚度直接成比例。
