MIT Researchers Developed Wearable Patch for Transdermal Drug Delivery
In some cases, it is important to deliver treatment through the skin, particularly for patients with skin conditions, so the drug can go directly to the area to promote wound healing, cosmetic and medical applications, and pain relief. It is an ideal process. However, delivering drugs through the skin is challenging since the skin’s tougher outer layer prohibits nearly all small molecules from penetrating.
Meeting the challenge
The drug delivery concept challenged MIT researchers. As a result of their study, they developed a wearable patch capable of applying painless ultrasonic waves to the skin. With the initial process, they can create small channels where drugs can pass through easily. With the novel approach, they can deliver treatments for various skin conditions. They can also adapt the system to deliver muscle relaxants, hormones, etc.
Game-changing alternative
Senior author of the study, associate professor Canan Dagdeviren at MIT’s Media Lab, said that the new system’s high repeatability and ease of use provide a viable alternative to consumers and patients suffering from various skin conditions, including premature aging of the skin. This method offers more local, controllable, comfortable, and less systemic toxicity.
When the research team started the project, they began by exploring alternative ways for drug delivery, as the most common methods are intravenous and oral deliveries. The researchers believe that drug delivery through the skin is a route that could provide more targeted treatment for specific applications.
According to them, the primary benefit of drug delivery through the skin is it bypasses the entire gastrointestinal tract. Thus, the delivery is more focused and targeted. You need to deliver a much larger dose with oral delivery because you have to compensate for the loss as the drug passes through the gastric system.
More efficient drug delivery
They designed a patch embedded with several round-shaped piezoelectric transducers to convert electric currents into mechanical energy. They embedded a polymeric cavity in each disc containing the drug molecules they dissolved in a liquid solution. Applying an electric current to the piezoelectric elements generates pressure waves in the solution to produce bubbles that burst when they come in contact with the skin. The bursting bubbles create microjets of fluid capable of penetrating the stratum corneum, the tough outer layer of the skin.
Their study showed that exposure to ultrasound enhances the skin’s permeability to tiny-molecule drugs. However, the existing techniques for this procedure need bulky equipment. So the researchers decided to work on transdermal drug delivery using a wearable, lightweight patch that will be easier for various applications.
The silicone-based polymer patch can stick to the skin without using tape. For their study, the research team tested the device by delivering niacinamide, a B vitamin used as an ingredient in moisturizers and sunscreens.
Using pig skin for their tests, the team showed that with the delivery of niacinamide using the ultrasound patch, the amount of drug delivered through the skin was 26 times greater than the amount that could penetrate the skin without ultrasonic support. They also compared their new delivery method with microneedling, sometimes used for drug delivery through the skin. They found that their process delivers the same amount of drugs in 30 minutes, whereas microneedling’s delivery will take more than six hours.
Localized drug delivery
In MIT’s current version of the patch, drugs can enter the skin for only a few millimeters, making it potentially useful for delivering drugs that act locally within the skin, such as vitamin C or niacinamide, for the treatment of the skin’s dark spots or age spots. Moreover, this can help deliver topical drugs to heal burnt skin. Burn victims usually develop chronic wounds, and using this device can support other technologies to heal their wounds.
The researchers are working on further modifications to the patch to increase the depth of penetration so that it can deliver drugs that must reach the bloodstream. They are also looking at delivering hormones and, later, implanting similar devices inside the body to deliver treatment drugs for cancer and other diseases.
The team is also working on optimizing the wearable patch further as they want to test the device soon on humans and repeat their experiments with drug molecules that are larger. They want to collect drug penetration profiles to determine which treatment drugs, such as insulin or hormones, they can deliver using the technology. Their success will provide many patients with a painless alternative instead of self-administering injections daily.