Sequential Coalescence Enabled Two-Step Microreactions in Triple-Core Double-Emulsion Droplets Triggered by an Electric Field
Sequential Coalescence Enabled Two-Step Microreactions in Triple-Core Double-Emulsion Droplets Triggered by an Electric Field
复制标题
电场触发的三核双乳液液滴中的顺序聚结实现了两步微反应
DOI：
10.1002/smll.201702188
复制
发表时间：
2017-12-13
期刊：
影响因子：
13.3
通讯作者：
Jiang, Hongyuan
中科院分区：
文献类型：
--
作者：
Jia, Yankai;Ren, Yukun;Jiang, Hongyuan
微流控乳化技术的进步使得精致的多核液滴的产生成为可能，这是适应微反应的有前途的结构。进行反应的基本要求是封装在这些液滴内的多个核的顺序聚结，因此，以受控的顺序将试剂混合在一起。在这里，微流体的方法报告的两步微反应的传导通过电融合内的双乳液液滴的三个核心。使用微毛细管玻璃装置，制造单分散水包油包水液滴，其中封装有三种隔室试剂。然后通过聚二甲基硅氧烷芯片施加AC电场以触发试剂的顺序混合，其中精确的顺序由内核的体积或电导率的差异来保证。每个液滴中的两步反应通过两次核心聚结来确保，根据不同的条件，这总共需要20-40 s。确定了用于内部液滴的顺序融合的AC信号的最佳参数。此外，该技术的能力是通过进行用于葡萄糖检测与双乳液液滴的酶催化反应证明。这种技术应有利于广泛的应用，需要在微米尺度的多步反应。
Advances in microfluidic emulsification have enabled the generation of exquisite multiple-core droplets, which are promising structures to accommodate microreactions. An essential requirement for conducting reactions is the sequential coalescence of the multiple cores encapsulated within these droplets, therefore, mixing the reagents together in a controlled sequence. Here, a microfluidic approach is reported for the conduction of two-step microreactions by electrically fusing three cores inside double-emulsion droplets. Using a microcapillary glass device, monodisperse water-in-oil-in-water droplets are fabricated with three compartmented reagents encapsulated inside. An AC electric field is then applied through a polydimethylsiloxane chip to trigger the sequential mixing of the reagents, where the precise sequence is guaranteed by the discrepancy of the volume or conductivity of the inner cores. A two-step reaction in each droplet is ensured by two times of core coalescence, which totally takes 20-40 s depending on varying conditions. The optimal parameters of the AC signal for the sequential fusion of the inner droplets are identified. Moreover, the capability of this technique is demonstrated by conducting an enzyme-catalyzed reaction used for glucose detection with the double-emulsion droplets. This technique should benefit a wide range of applications that require multistep reactions in micrometer scale.