Heo, Jeongmin Choi, Won Seok Key, Jaehong Youn, In chan Han, Sungmin 2024-01-12T06:31:57Z 2024-01-12T06:31:57Z 2023-08-17 2023-12 0020-7403 https://pubs.kist.re.kr/handle/201004/79725 The utilization of acoustic vortices presents a promising technique for contactless particle manipulation. However, existing methods for generating acoustic vortices typically rely on complex active driving systems and array ultrasound transducers. Therefore, more simplified and robust approaches to inducing acoustic vortices should be considered. With inspiring the fact that acoustic vortices can be generated by the differences in the height of adjacent sectors in conventional four-panel transducers, we aim to develop a single-channel acoustic vortex tweezer with a simplified driving system by incorporating attachable fan-shaped polydimethylsiloxane (PDMS) holographic lens. This passive lens structure with different heights in adjacent sectors can generate phase-modulated ultrasonic waves. Therefore, the interaction of phase-modulated waves passing through the lens is expected to result in a vortex-like beam. The available materials of fan-shaped lens are not limited to the PDMS. This lens type can be appropriately fabricated with an understanding of the sound of speed within the desired material and predetermined thickness, inducing π/2 phase difference in the adjacent lobes. As a result, the excited acoustic waves propagated through the lens were under mutual interaction without any active electrical setup, forming a null pressure region enveloped by four distinct acoustic lobes. We systemically investigated the tweezing potential using vortex-like waves. Several types of bioparticles were utilized in these investigations: microbubbles, polystyrene (PS) beads, and cancer cells. Our findings demonstrate that the transducer with lens is sufficiently capable of spatial manipulation of bioparticles. Remarkably, the microbubbles traveling at a flow velocity of 32 cm/s in a blood vessel-mimicking phantom were feasibly trapped in the proposed transducer. Furthermore, the spatial control of PS and cells with higher acoustic impedance was also feasible in static conditions. Consequently, the proposed transducer offers an economically and practically viable solution for various biomedical applications, such as drug delivery and cell-based bioengineering. English Pergamon Press Ltd. Single-channel acoustic vortex tweezer with attachable fan-shaped holographic lens Article 10.1016/j.ijmecsci.2023.108635 1 International Journal of Mechanical Sciences, v.260, no.15 International Journal of Mechanical Sciences 260 15 N scie scopus 001051407500001 Engineering, Mechanical Mechanics Engineering Mechanics Article CELL-SEPARATION MICROBUBBLES OPTICAL TWEEZERS Single-channel acoustic vortex tweezer Holographic technique Bioparticle manipulation Focused acoustic vortex