Surface acoustic wave (SAW) devices are increasingly applied in life science, biology, and point-of-care applications due to their combined acoustofluidic sensing and actuating properties. Despite the advances in this field, there remain significant gaps in interfacing hardware and control strategies to facilitate system integration with high performance and low cost. In this work, we present a versatile, and digitally controlled acoustofluidic platform by demonstrating key functions for biological assays such as droplet transportation and mixing using a closed-loop feedback control with image recognition. Moreover, we integrate optical detection by demonstrating in-situ fluorescence sensing capabilities with a standard camera and digital filters, bypassing the need for expensive and complex optical setups. The Acousto-Pi setup is based on open-source Raspberry Pi hardware and 3D printed housing, and the SAW devices are fabricated with piezoelectric thin film on a metallic substrate. The platform enables the control of droplet position and speed for sample processing (mixing and dilution of samples), as well as the control of temperature based on acousto-heating, offering embedded processing capability. It can be operated remotely while recording the measurements in cloud databases towards integrated in-field diagnostic applications such as disease outbreak control, mass healthcare screening and food safety.
|Number of pages||12|
|Journal||IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control|
|Early online date||15 Sep 2021|
|Publication status||E-pub ahead of print - 15 Sep 2021|