Focused ultrasound-mediated intranasal brain drug delivery technique (FUSIN).

The blood-brain barrier (BBB) is the major obstacle for brain drug delivery and limits the treatment options for central nervous system diseases. To circumvent the BBB, we introduce focused ultrasound-mediated intranasal brain drug delivery (FUSIN). FUSIN utilizes the nasal route for direct nose-to-brain drug administration, bypassing the BBB and minimizing systemic exposure to the major organs, such as heart, lung, liver, and kidney [1]. It also uses transcranial ultrasound energy focused at a targeted brain region to induce microbubble cavitation, enhancing the transport of intranasally administered agents at the FUS-targeted brain location. FUSIN is unique because it can achieve noninvasive and localized brain drug delivery with minimized systemic toxicity to other major organs. The goal of this paper is to provide a detailed protocol for FUSIN delivery to the mouse brain.•FUSIN delivery utilizes the nose-to-brain pathway for brain drug delivery.•FUSIN utilizes FUS combined with microbubble to significantly enhance the delivery efficiency of intranasally administered drugs to the FUS targeted brain regions.•FUSIN achieves efficient brain delivery with minimized systemic exposure in the major organs.