Robust fabrication of ultra-soft tunable PDMS microcapsules as a biomimetic model for red blood cells.
Robust fabrication of ultra-soft tunable PDMS microcapsules as a biomimetic model for red blood cells.
复制标题
稳健地制造超软可调 PDMS 微胶囊作为红细胞的仿生模型。
作者：
Chen Q
由薄膜包裹液芯的微胶囊在科学、医学和工业中有许多应用。在本文中，我们设计了一种悬浮的微胶囊，可以像红细胞（RBC）的流动和变形，作为一个有价值的工具，研究微血流动力学。一个可重构的和易于组装的3D嵌套玻璃毛细管装置被用来鲁棒地制造水-油-水双重乳液，然后通过交联的聚二甲基硅氧烷（PDMS）层涂层的液滴被转换成具有超弹性膜的球形微胶囊。所得胶囊是单分散的，在1%以内，并且可以制成宽范围的尺寸和膜厚度。我们使用渗透使直径为350 μm的初始球形胶囊收缩36%，膜厚度为它们半径的4%。因此，我们可以匹配减少的RBC体积，但不能匹配它们的双凹面形状，因为我们的胶囊采用了弯曲形状。我们比较了传播的初始球形和放气胶囊恒定体积流量下，在不同的限制圆柱形毛细管。我们发现，只有瘪胶囊变形广泛像红细胞在一个类似的范围内的毛细血管数Ca -粘性的弹性力的比率。类似的红细胞，微胶囊过渡从一个对称的“降落伞”到一个不对称的“拖鞋”样的形状作为Ca增加在生理范围内，表现出有趣的限制依赖的动力学。除了仿生RBC特性之外，可调超软微胶囊的高通量制造可以进一步功能化，并在其他科学和工程领域中找到应用。
Microcapsules with liquid cores encapsulated by thin membranes have many applications in science, medicine and industry. In this paper, we design a suspension of microcapsules which can flow and deform like red blood cells (RBCs), as a valuable tool to investigate microhaemodynamics. A reconfigurable and easy-to-assemble 3D nested glass capillary device is used to robustly fabricate water-oil-water double emulsions which are then converted into spherical microcapsules with hyperelastic membranes by cross-linking the polydimethylsiloxane (PDMS) layer coating the droplets. The resulting capsules are monodisperse to within 1% and can be made in a wide range of size and membrane thickness. We use osmosis to deflate by 36% initially spherical capsules of diameter 350 μm and a membrane thickness of 4% of their radius. Hence, we can match the reduced volume of RBCs but not their biconcave shape, since our capsules adopt a buckled shape. We compare the propagation of initially spherical and deflated capsules under constant volumetric flow in cylindrical capillaries of different confinements. We find that only deflated capsules deform broadly like RBCs over a similar range of capillary numbers Ca – the ratio of viscous to elastic forces. Similarly to the RBCs, the microcapsules transition from a symmetric ‘parachute’ to an asymmetric ‘slipper’-like shape as Ca increases within the physiological range, demonstrating intriguing confinement-dependent dynamics. In addition to biomimetic RBC properties, high-throughput fabrication of tunable ultra-soft microcapsules could be further functionalized and find applications in other areas of science and engineering.
复杂弹性结构中的模式切换现象
DOI：
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发表时间：
2012
期刊：
影响因子：
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作者：
Stephen Willshaw
通讯作者：
Stephen Willshaw