Research progress of focused ultrasound combined with microbubbles to open blood-brain barrier for brain-targeted delivery

Blood-brain barrier (BBB) is the most challengeable obstacle for brain-targeted drug delivery. The combination of focused ultrasound (FUS) and microbubbles provides a new way for brain-targeted drug delivery across BBB based on the cavitation effect. This review briefly described the recent research of FUS combined with microbubbles to enhance the BBB permeability for brain-targeted drug delivery. The contents included the FUS mechanism, the types of the commercial microbubbles, shell materials, inner gas and preparation techniques of microbubbles, the opening mechanism of FUS with microbubbles, and the safety consideration. FUS combined with microbubbles may be the effective strategy to improve the BBB permeability for brain-targeted delivery, which could provide references for the clinical applications.