KATHMANDU, FEBRUARY 3
When a single or few layers of graphite-the black tips on pencils-are isolated and rolled into a cylindrical structure, they form a wondrous nanomaterial known as Carbon Nanotube (CNT), which is 1,000 times thinner than human hair.
Professor Sumio Iijima introduced this material, which contains the same elements as coal or any other carbon material, to the scientific community in 1991. Since then, CNTs have played a key role in the development of groundbreaking innovations such as Vantablack (the blackest known object), notebook batteries, and, most recently, X-ray sources.
Carbon nanotube-based X-ray technology has the potential to transform X-ray systems by making them fully digital, compact, lightweight, and portable. This transformation in X-ray technology is analogous to paradigm shifts from yellow filament bulbs to LED bulbs or from gasoline cars to electric vehicles, which result in lower energy consumption and increased efficiency.
Scientists believe that using CNT X-ray technology, large CT scanners in hospitals could one day be small enough to fit inside a car, disassemble like Lego pieces, and be deployed to space stations and battlefields. Since X-ray systems are less common than mobile phones, profit-driven companies and grant-seeking researchers have not prioritized developing smaller and lighter X-ray machines.
However, Amar Prasad Gupta, a 33-year-old physics PhD from Lahan, Siraha, Nepal, had a different vision. During his graduate studies in South Korea, while cultivating his ideas and Carbon Nanotubes in his lab, he envisioned creating an X-ray system so small that it could be carried in one's pocket and was free of radiation and chemical hazards.
This device could be used in every school science lab to help students learn about X-ray physics. He faced the challenge of developing a small X-ray tube while leading a research group at Korea's CAT Beam Tech Co., Ltd. startup. As a side hobby, he and his biomedical engineer friend Kim Taeyoung set out to create not only a small X-ray tube, but also the world's smallest and lightest X-ray system.
After six months of continuous effort and numerous unsuccessful attempts, Dr. Gupta successfully developed an X-ray system smaller than a human hand, weighing only 86 grams, fitting easily into one's pocket, and powered solely by two AAA batteries.
He presented his research on this idea at the annual Radiological Society of North America meeting in 2023, which was held in Chicago last December, and was awarded the Trainee Research Prize for an outstanding contribution to RSNA by a physics trainee.
Professor Otto Zhou of the University of North Carolina, a pioneer in CNT X-ray technology, presented him with the award.
He stated that this was the first time he had seen the RSNA recognize a non-clinical, purely physics and engineering project with an award.
In its current form, the pocket-sized X-ray system is particularly effective at imaging soft materials like leaves and thin organic substances. It is appropriate for testing the operation of X-ray detectors and has the potential to serve as a portable skin radiotherapy machine.
Assistant Professor Dr. Arun Gupta of BPKIHS, who teaches Radiological and Nuclear Physics to MD Residents and is also a senior scientist at Northwestern University in the United States, believes that this pocket X-ray system can be a valuable and safe educational tool for teaching students about X-rays in class and providing a better understanding of X-ray physics.
Dr. Gupta hopes to use similar technology in the future to create a pocket-sized X-ray machine that can capture images of hands, legs, and teeth. "This innovation seeks to address the lack of adequate medical facilities in rural areas by providing valuable diagnostic capabilities to patients where they are most needed," he told THT.
Dr. Amar is currently a Postdoctoral Research Scholar at Harvard Medical School, which is affiliated with Massachusetts General Hospital in Boston, Massachusetts. He is involved in a project to develop a non-rotating CT scanner that is modular, portable, and can be sent to space stations and battlefields.
He has been a science enthusiast since high school and co-founded Golden Gate International College's science club. In 2011, he represented Nepal at the Asian Science Camp (Asian Version of Lindau Conference) held at KAIST in Daejeon, Korea, where he received a Bronze medal for his project titled "Mars, Mars, I am coming home; terraforming MARS for human survival." Subsequently, this medal played a pivotal role in securing a full ride through the Korean Government Scholarship program for undergraduate study in physics at Kyung Hee University.
He found his undergraduate studies monotonous and only discovered the true joy of science during his Master's and PhD. During his Master's program, he studied the growth of Carbon Nanotubes on a Steel substrate and co-created a tabletop high-resolution breast specimen X-ray imaging system.
He won the Best Oral Presentation award for his research at the 2019 International Conference of the Korean Society of Radiation Industry. He was also awarded the Best Thesis Award for his Master's research.
During his PhD, he continued his Master's research and worked on developing a vacuum-sealed digital X-ray tube based on optimized Carbon Nanotube electron emitters.
His concept for developing 2D to 3D CNT field emitters was presented at the 32nd International Conference of Diamond and Carbon Materials in 2022, where he received the Silver Elsevier Young Scholar Award. He also received the Best Oral Presentation Award at the Korean Association of Radiation Protection's 2023 Spring Conference for presenting his concept of developing a low-dose radiation source using CNT X-ray technology.
In 2023, he received the Trainee Research Award from the Radiological Society of North America (RSNA) for developing the world's smallest and lightest carbon nanotube-based pocket x-ray. It is powered by AAA batteries.
