LIMMS, CNRS-Institute of Industrial Science, IRL 2820, University of Tokyo, Tokyo 153-8505, Japan.
Institute of Industrial Science, The University of Tokyo, Meguro, Tokyo 153-8505, Japan.
Lab Chip. 2023 Jun 13;23(12):2854-2865. doi: 10.1039/d2lc01143c.
Droplet microfluidics has become a powerful tool in life sciences, underlying digital assays, single-cell sequencing or directed evolution, and it is making foray in physical sciences as well. Imaging and incubation of droplets are crucial, yet they are encumbered by the poor optical, thermal and mechanical properties of PDMS, a material commonly used in microfluidics labs. Here we show that Si is an ideal material for droplet chambers. Si chambers pack droplets in a crystalline and immobile monolayer, are immune to evaporation or sagging, boost the number of collected photons, and tightly control the temperature field sensed by droplets. We use the mechanical and optical benefits of Si chambers to image ≈1 million of droplets from a multiplexed digital assay - with an acquisition rate similar to the best in-line methods. Lastly, we demonstrate their applicability with a demanding assay that maps the thermal dependence of Michaelis-Menten constants with an array of ≈150 000 droplets. The design of the Si chambers is streamlined to avoid complicated fabrication and improve reproducibility, which makes Si a complementary material to PDMS in the toolbox of droplet microfluidics.
液滴微流控技术已经成为生命科学领域的强大工具，为数字分析、单细胞测序或定向进化提供了基础，它也正在物理科学领域中崭露头角。液滴的成像和孵育至关重要，但它们受到 PDMS（一种常用于微流控实验室的材料）较差的光学、热学和力学性能的限制。在这里，我们展示了硅是液滴腔室的理想材料。硅腔室以结晶且不可移动的单层形式包装液滴，能够防止蒸发或下垂，增加收集到的光子数量，并严格控制液滴感测到的温度场。我们利用硅腔室的机械和光学优势，对来自多重数字分析的 ≈100 万个液滴进行成像——其采集速度与最好的在线方法相似。最后，我们通过一项具有挑战性的分析证明了其适用性，该分析使用 ≈150000 个液滴阵列绘制米氏常数的热依赖性。硅腔室的设计简化了，以避免复杂的制造和提高可重复性，这使得硅成为液滴微流控工具盒中与 PDMS 互补的材料。
