Physicians use nuclear medicine imaging, such as single-photon emission computed tomography (SPECT), to observe internal organs and detect diseases. Current detectors for these scans are costly and difficult to produce, often relying on cadmium zinc telluride (CZT) or sodium iodide (NaI). CZT detectors can cost hundreds of thousands to millions of dollars and are fragile, while NaI detectors are less expensive but yield lower-quality images.
Researchers from Northwestern University and Soochow University in China have developed a new perovskite-based detector capable of capturing individual gamma rays for SPECT imaging with high precision. The study was published on August 30 in Nature Communications.
“Perovskites are a family of crystals best known for transforming the field of solar energy,” said Northwestern’s Mercouri Kanatzidis, the study’s senior author. “Now, they are poised to do the same for nuclear medicine. This is the first clear proof that perovskite detectors can produce the kind of sharp, reliable images that doctors need to provide the best care for their patients.”
“Our approach not only improves the performance of detectors but also could lower costs,” said co-corresponding author Yihui He, a professor at Soochow University. “That means more hospitals and clinics eventually could have access to the best imaging technologies.”
Kanatzidis holds positions as Charles E. and Emma H. Morrison Professor of Chemistry at Northwestern’s Weinberg College of Arts and Sciences and as a senior scientist at Argonne National Laboratory. He has studied perovskite materials extensively since 2012, including developing early solid-film solar cells made from perovskites and demonstrating their potential for detecting X-rays and gamma rays in 2013.
"This work demonstrates how far we can push perovskite detectors beyond the laboratory," Kanatzidis said. "When we first discovered in 2013 that perovskite single crystals could detect X-rays and gamma rays, we could only imagine their potential. Now, we’re showing that perovskite-based detectors can deliver the resolution and sensitivity needed for demanding applications like nuclear medicine imaging. It’s exciting to see this technology moving closer to real-world impact."
He led efforts on device design by creating a pixelated sensor architecture similar to those found in smartphone cameras. Experiments showed that this prototype detector achieved record energy resolutions and high single-photon imaging performance, allowing it to distinguish fine features just millimeters apart using medical radiotracers such as technetium-99m.
"Designing this gamma-ray camera and demonstrating its performance has been incredibly rewarding," He said. "By combining high-quality perovskite crystals with a carefully optimized pixelated detector and multi-channel readout system, we were able to achieve record-breaking energy resolution and imaging capabilities. This work shows the real potential of perovskite-based detectors to transform nuclear medicine imaging."
The research suggests these new detectors may allow shorter scan times or reduced radiation doses for patients due to higher sensitivity.
Northwestern spinout Actinia Inc., which has financial ties with both Kanatzidis and Northwestern University, is working with industry partners to commercialize this technology for clinical use. Because perovskites are easier to manufacture than traditional materials, these new devices may become more accessible across healthcare settings without sacrificing image quality.
“Demonstrating that perovskites can deliver single-photon gamma-ray imaging is a milestone,” He said. “It shows these materials are ready to move beyond the laboratory and into technologies that directly benefit human health. From here, we see opportunities to refine the detectors further, scale up production and explore entirely new directions in medical imaging.”
“High-quality nuclear medicine shouldn’t be limited to hospitals that can afford the most expensive equipment,” Kanatzidis said. “With perovskites, we can open the door to clearer, faster, safer scans for many more patients around the world. The ultimate goal is better scans, better diagnoses and better care for patients.”
The project received support from several organizations including U.S., Chinese national agencies, foundations in Jiangsu province (China), the Defense Threat Reduction Agency, the Consortium for Interaction of Ionizing Radiation with Matter University Research Alliance, the National Key R&D Program of China, the National Natural Science Foundation of China, as well as the Jiangsu Natural Science Foundation.