Acoustic tweezers for targeted drug delivery

Acoustic tweezers are a highly promising technology for targeted drug delivery thanks to their unique capabilities: (i) they can effectively operate in both in vitro and in vivo environments, (ii) they can manipulate a wide range of particle sizes and materials, and (iii) they can exert forces several orders of magnitude larger than competing techniques while remaining safe for biological tissues. In particular, tweezers capable of selectively capturing and manipulating objects in 3D with a single beam, known as 'single beam tweezers', open new perspectives for delivering drug carriers to precise locations. In this review, we first introduce the fundamental physical principles underlying the manipulation of particles using acoustic tweezers and highlight the latest advancements in the field. We then discuss essential considerations for the design of drug delivery carriers suitable for use with acoustic tweezers. Finally, we summarise recent promising studies that explore the use of acoustic tweezers for in vitro, ex vivo, and in vivo drug delivery.