Microbubble-Enhanced Transdermal Drug Delivery Sonoelectric Patch

Transdermal drug delivery systems are highly appealing as a convenient drug delivery manner applicable to a wide variety of drugs. While most delivery relies on only passive diffusion and suffers low transdermal efficiencies. Ultrasound motivation promotes drug transdermal penetration but still calls for improvement, because only a thin proportion of the ultrasound energy is applied on the drug delivery patch and most ultrasound energy is wasted in deeper portions of biotissues. In this work, we develop a transdermal patch for enhanced drug delivery. The combination of microsized air pockets and the piezoelectric soft structure enable the conversion of an intended proportion of ultrasound energy into electric energy. The intensified drug flow and synergistic ultrasound pressure and electric field function simultaneously to enhance drug transdermal delivery. The delivery efficacy is related to the power of the ultrasound motivation, the size of the microscopic air pockets, and the chemical structure of the drug molecules. The temperature of the patch within the delivery process remains in the safe range, and the mild temperature elevation causes color changes of the thermochromic patch, used to indicate effective ultrasound-patch matching. A model delivery patch for pain release is constructed, and animal experiments indicate that the drug blood concentrations are 100% higher than the delivery using only ultrasound and even more remarkably enhanced when compared to only electric-field-motivated delivery or static delivery without external motivations.