Tag Archives: Canan Dagdeviren

Sound waves for wearable patches that deliver drugs painlessly

Leave a reply

While watching this video I started wondering if they were testing their research on students but that’s not the case; these wearable patches were tested on porcine (pig) skin, which is quite similar to human skin, Note: They tested a B vitamin called niacinamide so, it’s highly unlikely the pigs suffered from it,

An April 20, 2023 news item on ScienceDaily announces the research into using ultrasonic waves for drug delivery,

The skin is an appealing route for drug delivery because it allows drugs to go directly to the site where they’re needed, which could be useful for wound healing, pain relief, or other medical and cosmetic applications. However, delivering drugs through the skin is difficult because the tough outer layer of the skin prevents most small molecules from passing through it.

In hopes of making it easier to deliver drugs through the skin, MIT [Massachusetts Institute of Technology] researchers have developed a wearable patch that applies painless ultrasonic waves to the skin, creating tiny channels that drugs can pass through. This approach could lend itself to delivery of treatments for a variety of skin conditions, and could also be adapted to deliver hormones, muscle relaxants, and other drugs, the researchers say.

…

An April 20, 2023 Massachusetts Institute of Technology (MIT) news release (also on EurekAlert), which originated the news item, provides technical details about the research, Note: A link has been removed,

“The ease-of-use and high-repeatability offered by this system provides a game-changing alternative to patients and consumers suffering from skin conditions and premature skin aging,” says Canan Dagdeviren, an associate professor in MIT’s Media Lab and the senior author of the study. “Delivering drugs this way could offer less systemic toxicity and is more local, comfortable, and controllable.”

MIT research 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” series, which showcases the outstanding work of researchers in the early stages of their independent careers. Other MIT authors include Research Assistant Colin Marcus and postdoc Md Osman Goni Nayeem. Nikta Amiri, Amit Kumar Bhayadia, and Amin Karami of the University of Buffalo are also authors of the paper.

A boost from sound waves

The researchers began this project as an exploration of alternative ways to deliver drugs. Most drugs are delivered orally or intravenously, but the skin is a route that could offer much more targeted drug delivery for certain applications.

“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,” Shah says. “This is a much more targeted, focused modality of drug delivery.”

Ultrasound exposure has been shown to enhance the skin’s permeability to small-molecule drugs, but most of the existing techniques for performing this kind of drug delivery require bulky equipment. The MIT team wanted to come up with a way to perform this kind of transdermal drug delivery with a lightweight, wearable patch, which could make it easier to use for a variety of applications.

The device that they designed consists of a patch embedded with several disc-shaped piezoelectric transducers, which can convert electric currents into mechanical energy. Each disc is embedded in a polymeric cavity that contains the drug molecules dissolved in a liquid solution. When an electric current is applied to the piezoelectric elements, they generate pressure waves in the fluid, creating bubbles that burst against the skin. These bursting bubbles produce microjets of fluid that can penetrate through the skin’s tough outer layer, the stratum corneum.

“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,” Karami says.

The patch is made of PDMS, a silicone-based polymer that can adhere to the skin without tape. In this study, the researchers tested the device by delivering a B vitamin called niacinamide, an ingredient in many sunscreens and moisturizers.

In tests using pig skin, the researchers showed that when they delivered niacinamide using the ultrasound 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.

The researchers also compared the results from their new device to microneedling, a technique sometimes used for transdermal drug delivery, which involves puncturing the skin with miniature needles. The researchers found that their patch was able to deliver the same amount of niacinamide in 30 minutes that could be delivered with microneedles over a six-hour period.

Local delivery

With the current version of the device, drugs can penetrate a few millimeters into the skin, making this approach potentially useful for drugs that act locally within the skin. These could include niacinamide or vitamin C, which is used to treat age spots or other dark spots on the skin, or topical drugs used to heal burns.

With further modifications to increase the penetration depth, this technique could also be used for drugs that need to reach the bloodstream, such as caffeine, fentanyl, or lidocaine. Dagdeviren also envisions that this kind of patch could be useful for delivering hormones such as progesterone. In addition, the researchers are now exploring the possibility of implanting similar devices inside the body to deliver drugs to treat cancer or other diseases.

The researchers are also working on further optimizing the wearable patch, in hopes of testing it soon on human volunteers. They also plan to repeat the lab experiments they did in this study, with larger drug molecules.

“After we characterize the drug penetration profiles for much larger drugs, we would then see which candidates, like hormones or insulin, can be delivered using this technology, to provide a painless alternative for those who are currently bound to self-administer injections on a daily basis,” Shah says.

Here’s a link to and a citation for the paper,

A Conformable Ultrasound Patch for Cavitation-Enhanced Transdermal Cosmeceutical Delivery by Chia-Chen Yu, Aastha Shah, Nikta Amiri, Colin Marcus, Md Osman Goni Nayeem, Amit Kumar Bhayadia, Amin Karami, Canan Dagdeviren. Advanced Materials Volume35, Issue 23 June 8, 2023 2300066 DOI: https://doi.org/10.1002/adma.202300066 First published online: 19 March 2023

This paper is open access.

Bend it, twist it, any way you want to—a foldable lithium-ion battery

Leave a reply

A Feb. 26, 2013 news item on ScienceDaily features an extraordinary lithium-ion battery,

Northwestern University’s Yonggang Huang and the University of Illinois’ John A. Rogers are the first to demonstrate a stretchable lithium-ion battery — a flexible device capable of powering their innovative stretchable electronics.

No longer needing to be connected by a cord to an electrical outlet, the stretchable electronic devices now could be used anywhere, including inside the human body. The implantable electronics could monitor anything from brain waves to heart activity, succeeding where flat, rigid batteries would fail.

Huang and Rogers have demonstrated a battery that continues to work — powering a commercial light-emitting diode (LED) — even when stretched, folded, twisted and mounted on a human elbow. The battery can work for eight to nine hours before it needs recharging, which can be done wirelessly.

The researchers at Northwestern have produced a video where they demonstrate the battery’s ‘stretchability’,

The Northwestern University Feb. 26, 2013 news release by Megan Fellman, which originated the news item, offers this detail,

“We start with a lot of battery components side by side in a very small space, and we connect them with tightly packed, long wavy lines,” said Huang, a corresponding author of the paper. “These wires provide the flexibility. When we stretch the battery, the wavy interconnecting lines unfurl, much like yarn unspooling. And we can stretch the device a great deal and still have a working battery.”

…

The power and voltage of the stretchable battery are similar to a conventional lithium-ion battery of the same size, but the flexible battery can stretch up to 300 percent of its original size and still function.

…

Huang and Rogers have been working together for the last six years on stretchable electronics, and designing a cordless power supply has been a major challenge. Now they have solved the problem with their clever “space filling technique,” which delivers a small, high-powered battery.

For their stretchable electronic circuits, the two developed “pop-up” technology that allows circuits to bend, stretch and twist. They created an array of tiny circuit elements connected by metal wire “pop-up bridges.” When the array is stretched, the wires — not the rigid circuits — pop up.

This approach works for circuits but not for a stretchable battery. A lot of space is needed in between components for the “pop-up” interconnect to work. Circuits can be spaced out enough in an array, but battery components must be packed tightly to produce a powerful but small battery. There is not enough space between battery components for the “pop-up” technology to work.

Huang’s design solution is to use metal wire interconnects that are long, wavy lines, filling the small space between battery components. (The power travels through the interconnects.)

The unique mechanism is a “spring within a spring”: The line connecting the components is a large “S” shape and within that “S” are many smaller “S’s.” When the battery is stretched, the large “S” first stretches out and disappears, leaving a line of small squiggles. The stretching continues, with the small squiggles disappearing as the interconnect between electrodes becomes taut.

“We call this ordered unraveling,” Huang said. “And this is how we can produce a battery that stretches up to 300 percent of its original size.”

The stretching process is reversible, and the battery can be recharged wirelessly. The battery’s design allows for the integration of stretchable, inductive coils to enable charging through an external source but without the need for a physical connection.

Huang, Rogers and their teams found the battery capable of 20 cycles of recharging with little loss in capacity. The system they report in the paper consists of a square array of 100 electrode disks, electrically connected in parallel.

I’d like to see this battery actually powering a device even though the stretching is quite alluring in its way. For those who are interested here’s a citation and a link to the research paper,

Stretchable batteries with self-similar serpentine interconnects and integrated wireless recharging systems by Sheng Xu, Yihui Zhang, Jiung Cho, Juhwan Lee, Xian Huang, Lin Jia, Jonathan A. Fan, Yewang Su, Jessica Su, Huigang Zhang, Huanyu Cheng, Bingwei Lu,           Cunjiang Yu, Chi Chuang, Tae-il Kim, Taeseup Song, Kazuyo Shigeta, Sen Kang, Canan Dagdeviren, Ivan Petrov  et al.   Nature Communications 4, Article number: 1543 doi: 10.1038/ncomms2553  Published 26 February 2013

The article is behind a paywall.