Naquin Ty, Jain Shivam, Zhang Jinxin, Xu Xianchen, Yao Gary, Naquin Chloe M, Yang Shujie, Xia Jianping, Wang Janna, Jimenez Sebastian, Huang Tony Jun
Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA.
Sens Actuators B Chem. 2024 Nov 1;418. doi: 10.1016/j.snb.2024.136294. Epub 2024 Jul 14.
Droplet microfluidics has emerged as a valuable technology for a multitude of chemical and biomedical applications, offering the capability to create independent microenvironments for high-throughput assays. Central to numerous droplet microfluidic applications is the picoinjection of materials into individual droplets, yet existing picoinjection methods often exhibit high power requirements, lack biocompatibility, and/or suffer from limited controllability. Here, we present an acoustofluidic picoinjector that generates acoustic pressure at the droplet interface to enable on-demand, energy-efficient, and biocompatible injection at high precision. We validate our platform by performing acid-base titrations by iteratively injecting picoliter volume reagents into droplets to induce pH transitions detectable by color change in solution. Additionally, we demonstrate the versatility of the acoustofluidic picoinjector in the synthesis of metallic nanoparticles, yielding highly monodisperse and reproducible particle morphologies compared to conventional bulk-phase techniques. By facilitating controlled delivery of reagents or biological samples with unparalleled accuracy, acoustofluidic picoinjection broadens the utility of droplet microfluidics for a myriad of applications in chemical and biological research.
微滴微流控技术已成为一种在众多化学和生物医学应用中具有重要价值的技术，它能够为高通量分析创建独立的微环境。在众多微滴微流控应用中，将材料皮升注射到单个微滴中至关重要，但现有的皮升注射方法往往功率需求高、缺乏生物相容性且/或可控性有限。在此，我们展示了一种声流体皮升注射器，它在微滴界面产生声压，以实现按需、节能且生物相容的高精度注射。我们通过将皮升体积的试剂反复注射到微滴中以引发可通过溶液颜色变化检测到的pH转变来进行酸碱滴定，从而验证了我们的平台。此外，与传统的体相技术相比，我们展示了声流体皮升注射器在金属纳米颗粒合成中的多功能性，可产生高度单分散且可重现的颗粒形态。通过以无与伦比的精度促进试剂或生物样品的可控递送，声流体皮升注射拓宽了微滴微流控技术在化学和生物学研究中众多应用的实用性。
