Three-dimensional single beam nano-acoustic tweezer using ring-shaped ultrahigh-frequency ultrasonic needle transducer.

Acoustic tweezers use sound waves to manipulate bioparticles and cells, offering safety benefits due to ultrasound's deep penetration. However, traditional single-beam acoustic tweezers (SBAT) struggle with 3D trapping and spatial resolution due to strong axial scattering radiation forces and limited frequencies. Here, we address these challenges by developing a ring-shaped ultra-high frequency ultrasonic needle transducer (RS-UHF-NT), enabling 3D single-cell trapping, nanoparticle manipulation, and direct targeting. The transducer's ring-shaped design with a central hole minimizes near-field axial scattering radiation forces, allowing 3D trapping, while the ultra-high frequency improves spatial resolution allowing nanoparticle manipulation. Additionally, the needle configuration enhances penetration depth by reducing the contact area, providing a direct approach to the target. Experimental results confirm SBAT's clinical potential for 3D nano-drug manipulation using the RS-UHF-NT.