Therapeutic Applications of Nanodroplets in Ultrasound: In Vitro and in Vivo Perspectives

Once the vapor pressure of a volatile liquid exceeds the ambient air pressure, the liquid droplets vaporize. This principle has led to the development of a type of nanodroplets that can transform into microbubbles upon ultrasound exposure. The unique phase-transition properties of these nanodroplets endow them with exceptional ultrasound imaging capabilities, while the mechanical effects of cavitation enhance their performance in targeted drug delivery. In this review, we will delve into the composition and phase transition mechanisms of these nanodroplets, as well as their potential clinical applications. Our discussion will not only highlight the diagnostic and therapeutic uses of ultrasound-activated nanodroplets for various medical conditions, but also address the challenges and potential strategies for their clinical translation.