Tunable patterning of bioparticles in ultrasonically oscillating microcavities
Phys. Rev. Applied 24, 024024 – Published 11 August, 2025
DOI: https://doi.org/10.1103/2hf6-8qgj
Abstract
Precise patterning of suspended inhomogeneities at the microscale has proven to be crucial for applications spanning a multitude of domains. The use of ultrasonic waves for microscale manipulation has emerged as a promising tool owing to its noninvasive and label-free nature. Alterations in acoustic-field configuration, a prerequisite to controlled pattern formation, have, however, mostly been achieved using arrays of piezoelectric sources, increasing the complexity of device operation. Here, we report tunable patterning of microparticles in a microfluidic cavity, driven by a single piezoelectric source. Our method exploits asymmetry incorporated in device design to generate diverse, frequency-dependent, acoustic potential landscapes. Remarkably, we show distinct microparticle aggregate patterns over a range of frequencies and capture underlying acoustic-field configurations by decoding nontrivial fluid-structure interactions. The hitherto unexplored design-incorporated asymmetries for reconfigurable aggregate patterning lays the groundwork for potential applications in microrobotics, microscale propulsion, and tissue engineering.
