Dec 14 2018
A novel ingestible capsule that can be controlled through Bluetooth wireless technology has been designed by researchers at MIT, Draper, and Brigham and Women’s Hospital.
MIT researchers have designed an ingestible sensor that can lodge in the stomach for a few weeks and communicate wirelessly with an external device. (Image credit: Courtesy of the researchers)
The new capsule can be modified to sense environmental conditions, deliver drugs, or both. It can reside in the human stomach for about one month, relaying data and responding to commands from a user’s smartphone.
Developed using 3D-printing technology, the capsules can possibly be deployed to deliver drugs for treating a range of diseases, especially in cases where drugs have to be taken over a prolonged period. The capsules could even be engineered to detect allergic reactions, infections, or other events, and subsequently discharge a drug in response.
Our system could provide closed-loop monitoring and treatment, whereby a signal can help guide the delivery of a drug or tuning the dose of a drug.
Giovanni Traverso, Department of Mechanical Engineering, MIT.
A visiting scientist, Traverso will be joining the faculty in 2019.
Such devices could even be used for communicating with other implantable and wearable medical devices, which could pool the data to be transmitted to the doctor’s or patient’s smartphone.
“We are excited about this demonstration of 3-D printing and of how ingestible technologies can help people through novel devices that facilitate mobile health applications,” stated Robert Langer, the David H. Koch Institute Professor and a member of MIT’s Koch Institute for Integrative Cancer Research.
Both Traverso and Langer are the senior authors of the study, which was recently published in Advanced Materials Technologies. The paper’s lead author is Yong Lin Kong, a former MIT postdoc and currently an assistant professor at the University of Utah.
Wireless communication
Over the past few years, Traverso, Langer, and their coworkers have been working on many different drug delivery capsules and ingestible sensors, which according to them would prove handy for long-term delivery of drugs that presently need to be administrated. They could even assist patients to stick to the stringent dosing regimens needed for malaria or HIV patients.
In their new study, the scientists set out to integrate many of the aspects they had formerly developed. In the year 2016, they created a star-shaped capsule that featured six arms, which fold up prior to being enclosed in a smooth capsule. Once the capsule is swallowed, it dissolves and the arms expand, enabling the device to reach into the stomach. Likewise, after being swallowed, the novel device unfolds into a Y-shape, allowing it to remain in the stomach for at least a month. It subsequently breaks into tinier pieces and passes via the digestive tract.
Four small compartments included in one of these arms can be loaded with many different drugs. Such drugs can then be packaged inside polymers that enable them to be released slowly over a number of days. According to the researchers, they could also develop the compartments that can be remotely opened via wireless Bluetooth communication.
Moreover, the device can even carry sensors that track the gastric environment and communicate information through a wireless signal. In earlier studies, the investigators created sensors that are capable of sensing vital signs like breathing rate and heart rate. In this latest study, the team showed that the new capsule can possibly be used for monitoring temperature and transmit that data directly to a user’s smartphone within arm’s length.
The limited connection range is a desirable security enhancement. The self-isolation of wireless signal strength within the user’s physical space could shield the device from unwanted connections, providing a physical isolation for additional security and privacy protection.
Yong Lin Kong, Assistant Professor and Study Lead Author, University of Utah.
To promote the development of all these intricate elements, the scientists decided to 3D print the capsules. This method enabled them to effortlessly integrate all the numerous components carried by the capsules, and to construct the capsule from alternating layers of flexible and stiff polymers, which aids it in enduring the stomach’s acidic environment.
Multimaterials 3D printing is a highly versatile manufacturing technology that can create unique multicomponent architectures and functional devices, which cannot be fabricated with conventional manufacturing techniques. We can potentially create customized ingestible electronics where the gastric residence period can be tailored based on a specific medical application, which could lead to a personalized diagnostic and treatment that is widely accessible.
Yong Lin Kong, Assistant Professor and Study Lead Author, University of Utah.
Early response
The team believes that this kind of sensor can be potentially used for diagnosing early signs of disease and subsequently respond with the right medication. For instance, it may be used for tracking specific people who are at increased risk of developing an infection, like patients who are receiving immunosuppressive or chemotherapy drugs. Upon detecting an infection, the capsule could start discharging antibiotics. Alternatively, if the device detects an allergic reaction, it could be engineered to discharge antihistamines.
“We’re really excited about the potential for gastric resident electronics to serve as platforms for mobile health to help patients remotely,” stated Traverso.
A tiny silver oxide battery drives the present version of the device; however, the team is investigating the potential of substituting the battery with other alternative power sources, like a stomach acid or external antenna.
The scientists are also looking at ways to devise other kinds of sensors that can possibly be integrated inside the capsules. In this study, the team tested the temperature sensor in pigs and predicted that they could soon be able to test the ingestible sensors in human patients within a couple of years. In this regard, the researchers have launched a company that is working to devise the technology for human applications.
The study was supported by the Bill and Melinda Gates Foundation and the National Institutes of Health through Draper.
Other authors of the study include Xingyu Zou, Caitlin McCandler, Ameya Kirtane, Shen Ning, Jianlin Zhou, Abubakar Abid, Mousa Jafari, Jaimie Rogner, Daniel Minahan, Joy Collins, Shane McDonnell, Cody Cleveland, Taylor Bensel, Siid Tamang, Graham Arrick, Alla Gimbel, Tiffany Hua, Udayan Ghosh, Vance Soares, Nancy Wang, Aniket Wahane, Alison Hayward, Shiyi Zhang, and Brian Smith.