Focused Ultrasound-Enhanced Nanoparticle Delivery in a Mouse Model for Tumor Therapy

Begin with an anesthetized tumor-bearing mouse and shave its head.

Place it in an MRI scanner integrated with the focused ultrasound system.

The initial MRI scan locates the brain tumor and nearby blood vessels.

Inject a contrast agent intravenously, then administer fluorescently labeled nanoparticles coated onto gas-filled microbubbles.

The contrast agent and microbubbles circulate and reach the brain.

Apply focused ultrasound waves to the tumor site.

The ultrasound causes the microbubbles to expand and contract, disrupting the tight junctions of the blood-brain barrier, or BBB, near the tumor.

This creates temporary, localized openings in the vessel, allowing the contrast dye to enter, confirming BBB disruption.

The microbubbles break, releasing the nanoparticles from their surfaces.

These nanoparticles enter the brain tissue via the BBB opening and accumulate within the tumor and its surroundings.

Fluorescence imaging tracks nanoparticle localization in the tumor region, providing insight into nanoparticle distribution for neurotherapeutic drug delivery.