The skin is an interesting course for drug distribution since it allows drugs to go straight to the location where they’re required, which could be beneficial for wound remedial, pain relief, or other medical and cosmetic applications. However, distributing drugs through the skin is problematic since the tough external layer of the skin prevents most small molecules from passing through it.
In anticipation of creation, it is easier to deliver drugs through the skin, MIT scientists have established a wearable patch that spreads on painless ultrasonic waves to the skin, generating tiny networks that drugs can pass through. This method could lend itself to administering treatments for an assortment of skin conditions, and could also be altered to deliver hormones, muscle relaxants, and other drugs, the scientists say.
The ease of use and high repeatability presented by this system, provide a game-changing substitute to patients and consumers suffering from skin conditions and untimely skin aging, says Canan Dagdeviren, an assistant professor in MIT’s Media Lab and the primary author of the study. “Delivering drugs in this manner could offer less complete toxicity and is more local, comfortable, and manageable.”
MIT study assistants Chia-Chen Yu and Aastha Shah are the lead authors of the paper, which appears in Advanced Materials, as part of the journal’s “Rising Stars” sequence, which displays the outstanding work of scientists in the initial stages of their independent careers. Other MIT authors comprise Investigate Assistant Colin Marcus and postdoc Md Osman Goni Nayeem. Nikta Amiri, Amit Kumar Bhayadia, and Amin Karami of the University of Buffalo are also involved in the paper.
The scientists commenced this project as an examination of alternative ways to deliver drugs. Most medications are delivered orally or intravenously, but the skin is a path that could suggest much more targeted drug distribution for certain applications.
The chief benefit of skin is that you evade the whole gastrointestinal tract. With oral distribution, you have to distribute a much greater dose to account for the loss that occurs in the gastric system, Shah says. “This is a much more precise, focused mode of drug delivery.”
Ultrasound has been revealed to increase the skin’s penetrability to small-molecule drugs, but most of the current systems for the execution of this kind of drug delivery necessitate bulky equipment. The MIT team needed to come up with a method to achieve this kind of transdermal drug delivery with a lightweight, wearable patch, which could make it easier to customize for an assortment of applications.
The device that was designed comprises a patch implanted with numerous disc-shaped piezoelectric transducers, which can alter electric currents into mechanical energy. Each disc is surrounded by a polymeric cavity that comprises the drug molecules dissolved in a liquid solution. When an electric current is applied to the piezoelectric elements, they produce pressure waves in the fluid, generating bubbles that erupt against the skin. These bursting bubbles produce microjets of fluid that can infiltrate through the skin’s tough external layer, the stratum corneum.
This method opened the doors to using vibrations to improve drug delivery. Several parameters result in the creation of different kinds of waveform patterns. Both mechanical and biological features of drug delivery can be enhanced by this new toolset, Karami says.
The patch is made of PDMS, a silicone-based polymer that can stick to to the skin without tape. In this study, the scientists tried the device by administering a B vitamin called niacinamide, a component in many sunscreens and moisturizers.
In tests utilizing pig skin, the scientists exhibited that when they distributed niacinamide using the ultrasound patch, the quantity of drug that penetrated the skin was 26 times more than the quantity that could pass into the skin without ultrasonic support.
The scientists also related the results from their new device to micro-needling, a procedure occasionally used for transdermal drug delivery, which comprises piercing the skin with miniature needles. The scientists found that the patch was able to distribute the same quantity of niacinamide in 30 minutes that could be distributed with microneedles over six hours.
With the existing version of the device, drugs can enter a few millimeters into the skin, making this method potentially useful for drugs that are administered locally within the skin. These could comprise niacinamide or vitamin C, which is used to treat age spots or other discolored spots on the skin, or current drugs used to heal burns.
With further alterations to enhance the penetration depth, this system could also be used for drugs that are required to reach the bloodstream, such as caffeine, fentanyl, or lidocaine. Dagdeviren also imagines that this form of patch could be beneficial for delivering hormones such as progesterone. Additionally, the scientists are now discovering the prospect of implanting similar devices inside the body to deliver drugs to treat cancer or other diseases.
The scientists are also working on further enhancing the wearable patch, in hopes of testing it soon on humans. They also propose to replicate the lab experiments they did in this study, with larger drug particles.
After we illustrate the drug penetration profiles for much larger drugs, we would then see which contenders, like hormones or insulin, can be distributed using this expertise, to deliver a painless substitute for those who are presently bound to self-administer injections daily, Shah says.
