Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA.
Lab Chip. 2020 Apr 7;20(7):1298-1308. doi: 10.1039/d0lc00106f. Epub 2020 Mar 20.
Separation of nano/microparticles based on surface acoustic waves (SAWs) has shown great promise for biological, chemical, and medical applications ranging from sample purification to cancer diagnosis. However, the permanent bonding of a microchannel onto relatively expensive piezoelectric substrates and excitation transducers renders the SAW separation devices non-disposable. This limitation not only requires cumbersome cleaning and increased labor and material costs, but also leads to cross-contamination, preventing their implementation in many biological, chemical, and medical applications. Here, we demonstrate a high-performance, disposable acoustofluidic platform for nano/microparticle separation. Leveraging unidirectional interdigital transducers (IDTs), a hybrid channel design with hard/soft materials, and tilted-angle standing SAWs (taSSAWs), our disposable acoustofluidic devices achieve acoustic radiation forces comparable to those generated by existing permanently bonded, non-disposable devices. Our disposable devices can separate not only microparticles but also nanoparticles. Moreover, they can differentiate bacteria from human red blood cells (RBCs) with a purity of up to 96%. Altogether, we developed a unidirectional IDT-based, disposable acoustofluidic platform for micro/nanoparticle separation that can achieve high separation efficiency, versatility, and biocompatibility.
基于表面声波（SAW）的纳米/微米颗粒分离在生物、化学和医学应用中具有广阔的前景，从样品纯化到癌症诊断等领域都有涉及。然而，将微通道永久键合到相对昂贵的压电基板和激励换能器上，使得 SAW 分离设备无法一次性使用。这种局限性不仅需要繁琐的清洁过程，增加劳动力和材料成本，还会导致交叉污染，限制了它们在许多生物、化学和医学应用中的实施。在这里，我们展示了一种用于纳米/微米颗粒分离的高性能、一次性声流控平台。利用单向叉指换能器（IDT）、硬/软材料混合通道设计和倾斜角度驻波（taSSAW），我们的一次性声流控设备实现了与现有永久性键合、不可一次性使用的设备相当的声辐射力。我们的一次性设备不仅可以分离微米颗粒，还可以分离纳米颗粒。此外，它们可以分离细菌和人红细胞（RBC），纯度高达 96%。总之，我们开发了一种基于单向 IDT 的一次性声流控微纳颗粒分离平台，具有高效率、多功能性和生物相容性。
