Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, IN, 46556, USA.
Sci Rep. 2023 Jan 5;13(1):184. doi: 10.1038/s41598-023-27470-1.
Droplet microfluidics offers a platform from which new digital molecular assay, disease screening, wound healing and material synthesis technologies have been proposed. However, the current commercial droplet generation, assembly and imaging technologies are too expensive and rigid to permit rapid and broad-range tuning of droplet features/cargoes. This rapid prototyping bottleneck has limited further expansion of its application. Herein, an inexpensive home-made pipette droplet microfluidics kit is introduced. This kit includes elliptical pipette tips that can be fabricated with a simple DIY (Do-It-Yourself) tool, a unique tape-based or 3D printed shallow-center imaging chip that allows rapid monolayer droplet assembly/immobilization and imaging with a smart-phone camera or miniature microscope. The droplets are generated by manual or automatic pipetting without expensive and lab-bound microfluidic pumps. The droplet size and fluid viscosity/surface tension can be varied significantly because of our particular droplet generation, assembly and imaging designs. The versatility of this rapid prototyping kit is demonstrated with three representative applications that can benefit from a droplet microfluidic platform: (1) Droplets as microreactors for PCR reaction with reverse transcription to detect and quantify target RNAs. (2) Droplets as microcompartments for spirulina culturing and the optical color/turbidity changes in droplets with spirulina confirm successful photosynthetic culturing. (3) Droplets as templates/molds for controlled synthesis of gold-capped polyacrylamide/gold composite Janus microgels. The easily fabricated and user-friendly portable kit is hence ideally suited for design, training and educational labs.
液滴微流控技术提供了一个平台，在此基础上提出了新的数字分子分析、疾病筛查、伤口愈合和材料合成技术。然而，当前的商业液滴生成、组装和成像技术过于昂贵且僵化，无法快速广泛地调整液滴特征/货物。这种快速原型瓶颈限制了其应用的进一步扩展。在此，介绍了一种廉价的自制移液器液滴微流控套件。该套件包括可以用简单的 DIY（自己动手）工具制作的椭圆形移液器吸头，独特的基于胶带或 3D 打印的浅中心成像芯片，允许使用智能手机摄像头或微型显微镜快速进行单层液滴组装/固定和成像。通过手动或自动移液来生成液滴，无需昂贵的实验室专用微流控泵。由于我们特殊的液滴生成、组装和成像设计，可以显著改变液滴的大小和流体的粘度/表面张力。该快速原型套件的多功能性通过三个具有代表性的应用来展示，这些应用可以从液滴微流控平台中受益：（1）作为微反应器的液滴，用于 PCR 反应和反转录，以检测和定量目标 RNA。（2）作为微隔室的液滴，用于螺旋藻培养，并且在含有螺旋藻的液滴中的光学颜色/浊度变化证实了成功的光合培养。（3）作为模板/模具的液滴，用于控制合成金覆盖的聚丙烯酰胺/金复合的单分体型 Janus 微凝胶。因此，这种易于制造且用户友好的便携式套件非常适合设计、培训和教育实验室。
