Fig. 4: The characteristics of drug delivery based on microexplosive shockwaves.

a The effect of drug injection by shockwave under different L1 values. b Under the condition of different L1 values, the relationship between the injection velocity and time of a single particle of powder under the application of the shockwave. c Under different L1 values, the change in kinetic energy of the drug powder under the application of the shockwave. d Effect of the hole diameter D1 of the transparent cover on the kinetic energy of drug powder injection under the shockwave. e The vibration displacement of the microsystem in the x, y, and z directions during the shockwave. f The manufacturing process of the implantable shockwave-based drug delivery microsystem: (i) 3D printing and processing of the tubular shell, transparent cover, and flexible push rod, (ii) preparation of PDMS film, copper azide, circuit module and semiconductor bridge, and (iii)) microsystem assembly