California, US: In order to monitor changes in the growth of tumors under the skin, a small, autonomous device with a stretchable and flexible sensor has been designed by the Bao Group of Stanford University experts.
The battery-powered, non-invasive device has a sensitivity of one-hundredth of a millimeter and is capable of wirelessly transmitting data to a smartphone app in real-time (10 micrometers).
Bao Group claims that their FAST instrument, which stands for “Flexible Standalone Sensor That Measures Tumors,” is an entirely new, quick, inexpensive, and precise method of determining the effectiveness of cancer medications. The innovation could open the door for creative new approaches to treating cancer on a larger scale. The results of the study have just been released in the journal Science Achievements.
Researchers test thousands of potential cancer medications on mice each year that have subcutaneous tumors. Since techniques to measure tumor regression following drug treatment require weeks to read a response, few new treatments reach patients, and the process of researching new drugs is lengthy. Drug screening is difficult and time-consuming because of the biological diversity inherent in tumors, the limitations of current assessment techniques, and the small sample sizes that are typically used.

Mr. Alex Abramson, the study’s main author and a recent postdoctoral researcher in the lab of Zhennan Bao, the CC Li Professor of Chemical Engineering at the Stanford School of Engineering, remarked that “in some cases, the tumors under observation need to be measured manually with a caliper.”
It is not ideal to employ forceps that resemble metal calipers to measure soft tissue, and radiological methods cannot give the continuous data required for real-time evaluation. While caliper and bioluminescence measures frequently require week-long follow-up periods to interpret changes in tumor growth, FAST can detect changes in tumor volume on a minute timescale.
FAST- The latest advancement in Oncology
The FAST sensor is made of a stretchable, skin-like polymer that is flexible and coated in gold. Mr. Yasir Khan and Mr. Naoji Matsuhisa, co-authors and former Ph.D. students, created a compact electronic backpack that includes this sensor. The apparatus detects the membrane’s stress, or how much it stretches or contracts, and sends this information to a smartphone. Potential therapies linked to tumor size regression can be swiftly and accurately disregarded as ineffective or accelerated for further investigation using the FAST backpack.
The researchers claim that the novel technology delivers at least three noteworthy advancements based on the mouse tests. Due to the sensor’s physical attachment to the mouse and its continued presence there throughout the experiment, the device offers first and foremost continuous monitoring. Second, the flexible sensor can assess shape changes that are challenging to detect with existing techniques because it can wrap around the tumor. Third, FAST is non-intrusive and autonomous. Unlike a Band-Aid, it is affixed to the skin, powered by a battery, and linked to a wireless network. After the sensor is installed, scientists don’t need to actively handle the mice because they may wander about freely without tripping over the device or wires. FAST packs may be put together for around $60, are reusable, and take only a few minutes to attach to a mouse.

FAST is designed as a skin-like polymer covered with a layer of gold, which when stretched causes minute fissures that alter the material’s electrical conductivity. Stretching the material will result in more cracks, which will increase the electrical resistance in the sensor. The compression promotes conductivity by bringing the cracks back into contact.
Mr. Abramson and co-author Mr. Matsuhisa, Associate University of Tokyo, talked about how changes in size and volume can be used to measure how cracks spread and how conductivity changes exponentially.
The concern that the sensor would obstruct measurements by applying too much pressure to the tumor and crushing it was one obstacle the researchers had to get past. To reduce this risk, they made the sensor as elastic and flexible as the skin itself by carefully matching the mechanical properties of the flexible material to those of the skin.
Mr. Abramson pointed out that, “It’s a deceptively simple design, but these inherent benefits should be of great interest to the pharmaceutical and oncology communities. FAST can significantly speed up, automate, and reduce the cost of the cancer therapy screening process.”