FIG. 2.

Schematic representation of microbubbles precursors (A) and functionalized microbubbles (B). (A) Superheated, liquid perfluorocarbon nanodroplets are stabilized by a surfactant layer and can be vaporized with ultrasound or laser pulses (a); fluorescently labeled nanoparticles can generate microbubbles when exposed to laser light (b); and polymeric nanoparticles encapsulating a small gas core can be used as sustainable microbubble precursors (c). (B) Microbubbles can be functionalized by attaching targeting ligands (a); loading them with drug-containing nanoparticles (b) or make them suitable for multimodal imaging by covering them with plasmonic nanoparticles (c).