Gumuscu Burcu, Eijkel Jan C T
BIOS Lab-on-a-Chip Group, MESA+ Institute for Nanotechnology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands.
California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA, USA.
Methods Mol Biol. 2018;1771:225-238. doi: 10.1007/978-1-4939-7792-5_18.
We present a capillary pinning technique that gives complete control on the local patterning of hydrogel structures in closed microchips. The technique relies on selective trapping of liquids at predefined locations in a microchip using capillary barriers. In selective patterning, the abrupt expansion in the cross-sectional geometry of a microchannel at capillary barriers results in a confined advancement of the liquid-air meniscus. This protocol describes a detailed procedure to design and fabricate microarrays of different hydrogel types, fabricated with photopolymerization or thermogelation. The process can be subdivided into two parts. First, a PDMS microchip containing microfeatures with customized patterns is fabricated. Second, the microchip is filled with a hydrogel precursor to be cross-linked by either photopolymerization or thermogelation. The production of the microchip takes approximately 2 days, depending on the substrate selection. Preparation of the hydrogel solutions takes 1-2 h, whereas the patterning and reaction to cross-link the hydrogels is completed in a few minutes.
我们展示了一种毛细管固定技术，该技术能够完全控制封闭微芯片中水凝胶结构的局部图案化。该技术依赖于使用毛细管屏障在微芯片中的预定义位置选择性捕获液体。在选择性图案化中，微通道在毛细管屏障处横截面几何形状的突然扩展导致液 - 气弯月面的受限推进。本方案描述了设计和制造不同水凝胶类型微阵列的详细程序，这些微阵列通过光聚合或热凝胶化制备。该过程可分为两部分。首先，制造一个包含具有定制图案微特征的聚二甲基硅氧烷（PDMS）微芯片。其次，用通过光聚合或热凝胶化交联的水凝胶前体填充微芯片。根据底物选择，微芯片的制作大约需要2天。水凝胶溶液的制备需要1 - 2小时，而水凝胶图案化和交联反应在几分钟内即可完成。
