Chen Yihang, Zhang Shiming, Cui Qingyu, Ni Jiahua, Wang Xiaochen, Cheng Xuanbing, Alem Halima, Tebon Peyton, Xu Chun, Guo Changliang, Nasiri Rohollah, Moreddu Rosalia, Yetisen Ali K, Ahadian Samad, Ashammakhi Nureddin, Emaminejad Sam, Jucaud Vadim, Dokmeci Mehmet R, Khademhosseini Ali
Center for Minimally Invasive Therapeutics (C-MIT), University of California-Los Angeles, Los Angeles, CA 90095, USA and California NanoSystems Institute, University of California-Los Angeles, Los Angeles, CA 90095, USA and Department of Materials Science and Engineering, University of California-Los Angeles, Los Angeles, CA 90095, USA.
Center for Minimally Invasive Therapeutics (C-MIT), University of California-Los Angeles, Los Angeles, CA 90095, USA and California NanoSystems Institute, University of California-Los Angeles, Los Angeles, CA 90095, USA and Department of Bioengineering, University of California-Los Angeles, Los Angeles, CA 90095, USA.
Lab Chip. 2020 Nov 10;20(22):4205-4214. doi: 10.1039/d0lc00446d.
Microchannels in hydrogels play an essential role in enabling a smart contact lens. However, microchannels have rarely been created in commercial hydrogel contact lenses due to their sensitivity to conventional microfabrication techniques. Here, we report the fabrication of microchannels in poly(2-hydroxyethyl methacrylate) (poly(HEMA)) hydrogels that are used in commercial contact lenses with a three-dimensional (3D) printed mold. We investigated the corresponding capillary flow behaviors in these microchannels. We observed different capillary flow regimes in these microchannels, depending on their hydration level. In particular, we found that a peristaltic pressure could reinstate flow in a dehydrated channel, indicating that the motion of eye-blinking may help tears flow in a microchannel-containing contact lens. Colorimetric pH and electrochemical Na+ sensing capabilities were demonstrated in these microchannels. This work paves the way for the development of microengineered poly(HEMA) hydrogels for various biomedical applications such as eye-care and wearable biosensing.
水凝胶中的微通道对于实现智能隐形眼镜起着至关重要的作用。然而，由于商业水凝胶隐形眼镜对传统微加工技术敏感，很少有微通道被制造出来。在此，我们报告了使用三维（3D）打印模具在用于商业隐形眼镜的聚（甲基丙烯酸羟乙酯）（聚（HEMA））水凝胶中制造微通道的方法。我们研究了这些微通道中相应的毛细流动行为。我们观察到这些微通道中存在不同的毛细流动状态，这取决于它们的水合水平。特别地，我们发现蠕动压力可以恢复脱水通道中的流动，这表明眨眼动作可能有助于含微通道的隐形眼镜中的泪液流动。在这些微通道中展示了比色pH传感和电化学Na +传感能力。这项工作为开发用于各种生物医学应用（如眼部护理和可穿戴生物传感）的微工程聚（HEMA）水凝胶铺平了道路。
