Fig. 1: Concept of focal aggregation and uncaging of ultrasound-controlled drug carriers.

a UC-carriers are continuously infused (blue particles within the capillary) intravenously, which circulate stably. b UC-carriers are first aggregated locally by acoustic radiation forces generated by ultrasound waves (blue). c The locally concentrated UC-carriers are then uncaged to release drugs using acoustic uncaging forces produced by ultrasound waves (green). d Small molecules diffuse across the intact BBB reaching their molecular targets (ultrasound beam is not to scale).