Super-resolved extravascular monitoring technique using recondensation of theranostic nanodroplets

Phase-change nanodroplets (PCNDs), known as customizable and controllable theranostic agents, have proven potential in many ultrasound applications. However, obtaining the accurate extravascular distribution of PCNDs in vivo is still a challenge with current ultrasound monitoring techniques, which would thwart further quantitative analysis. Here, a super-resolved extravascular monitoring technique was demonstrated using the stochastic recondensation signal of customized mixed-core PCNDs as the source signal for monitoring. A "blink map" method was used to improve the recognition of the pattern of recondensation signals and get reliable source signals in the presence of inherent interferences in vivo. The super-resolved mapping of PCNDs in a mouse tumor model was given as the preliminary result, indicating the feasibility of our monitoring technique in vivo.