Wearable patch improves drug delivery through the skin using sound
A new approach to topical delivery of therapies may be used to treat a variety of skin conditions, according to MIT researchers.
The wearable patch they have developed employs ultrasonic waves created by piezoelectric transducers to move drug molecules more effectively through the stratum corneum. The researchers say the system could be useful for wound healing, pain relief, or other medical and cosmetic applications by offering more targeted drug delivery.
The paper, published in Advanced Materials, describes the device they developed as a wearable patch embedded with several disc-shaped piezoelectric transducers that can convert electric currents into mechanical energy. According to the researchers, the discs are embedded in a polymeric cavity that contains the drug molecules dissolved in a liquid solution. When an electric current is applied to the transducers, pressure waves in the fluid create bubbles that burst in contact with the skin, producing microjets that can penetrate through the stratum corneum. The patch is made of PDMS, a silicone-based polymer that adheres to human skin without tape.
“The main benefit with skin is that you bypass the whole gastrointestinal tract. With oral delivery, you have to deliver a much larger dose in order to account for the loss that you would have in the gastric system,” said MIT research assistant and co-lead author Aastha Shah in a press release. Shah is a graduate student in the MIT Media Lab.
The research conducted at MIT showed that when they delivered niacinamide with this patch, the amount of drug that penetrated the skin was 26 times greater than the amount that could pass through the skin without ultrasonic assistance.
“This works open the door to using vibrations to enhance drug delivery. There are several parameters that result in generation of different kinds of waveform patterns. Both mechanical and biological aspects of drug delivery can be improved by this new toolset,” added co-author Amin Karami, PhD. Dr. Karmai is an Associate Professor in the Department of Mechanical and Aerospace Engineering, School of Engineering and Applied Sciences, State University of New York at Buffalo.