State Key Laboratory of High-Performance Complex Manufacturing, College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China.
Institute of Polymer Technology (LKT), Friedrich-Alexander-University Erlangen-Nurnberg, Am Weichselgarten 9, 91058 Erlangen, Germany.
Sensors (Basel). 2022 Feb 8;22(3):1269. doi: 10.3390/s22031269.
Acoustic manipulation of microparticles and cells has attracted growing interest in biomedical applications. In particular, the use of acoustic waves to concentrate particles plays an important role in enhancing the detection process by biosensors. Here, we demonstrated microparticle concentration within sessile droplets placed on the hydrophobic surface using the flexural wave. The design benefits from streaming flow induced by the Lamb wave propagated in the glass waveguide to manipulate particles in the droplets. Microparticles will be concentrated at the central area of the droplet adhesion plane based on the balance among the streaming drag force, gravity, and buoyancy at the operating frequency. We experimentally demonstrated the concentration of particles of various sizes and tumor cells. Using numerical simulation, we predicted the acoustic pressure and streaming flow pattern within the droplet and characterized the underlying physical mechanisms for particle motion. The design is more suitable for micron-sized particle preparation, and it can be valuable for various biological, chemical, and medical applications.
声操控微颗粒和细胞在生物医学应用中引起了越来越多的关注。特别是，利用声波来浓缩颗粒在增强生物传感器的检测过程中起着重要作用。在这里，我们使用弯曲波在放置在疏水表面上的液滴内演示了微颗粒的浓缩。该设计受益于在玻璃波导中传播的兰姆波产生的流动，以操纵液滴中的颗粒。根据操作频率下的流动阻力、重力和浮力之间的平衡，微颗粒将集中在液滴附着平面的中心区域。我们通过实验演示了各种大小的颗粒和肿瘤细胞的浓缩。通过数值模拟，我们预测了液滴内的声压和流动模式，并对颗粒运动的潜在物理机制进行了特征化。该设计更适合于微米级颗粒的制备，对于各种生物、化学和医学应用都具有重要价值。
