<p>A method of delivering a therapeutic substance to tissue comprises delivering the therapeutic substance and nanoparticles to the tissue, the nanoparticles having a diameter in the range from 10 to 1000 nm and surface features having a depth in the range from 5 to 50 nm, and insonating the tissue with pressure waves. Corresponding particles, and associated methods of controlling and imaging the treatment and delivery are also disclosed.</p>
