Developing a multi-sample acoustofluidic device for high-throughput cell aggregation

Plug-and-play acoustofluidic devices are highly promising for dexterously aggregating microparticles owing to the advantages of being contactless, label-free, and cost-efficient. Despite the extensive progress, existing acoustofluidic devices are largely limited to addressing a single sample per device, lacking the ability to address multiple samples for high-throughput operations in a single acoustofluidic device. In this work, we report a high-throughput multi-sample acoustofluidic aggregation device that enables manipulation of up to 12 samples simultaneously using a single reusable acoustic tweezer. The key design of the multi-sample acoustofluidic device lies in the utilization of a polydimethylsiloxane frame as a selective acoustic-absorbing feature to create asymmetric acoustic waves over multiple detachable superstrates in a single device. This approach is distinct from conventional strategies which mostly have involved modifying the superstrates or tuning the settings for individual superstrates. We demonstrate that the proposed acoustofluidic device can efficiently aggregate multiple samples of various compositions ranging from non-bioactive microparticles to bioactive cells, as well as a range of object sizes spanning from 0.6 µm to 13 µm. Given its merits of simplicity, cost-efficiency and high throughput, the proposed platform could be useful for biomedical applications requiring large-scale operations, such as 3D tumor spheroids and bio-sensors. © 2023 IOP Publishing Ltd