The National University of Singapore (NUS) has discovered a new type of nanocrystals that enables cost-effective and safer medical imaging in X-ray and computerized tomography (CT). The team of chemists from this university, in alliance with other researchers from other countries, has developed a nanocrystal called lead halide perovskite. It has the ability of high sensitivity towards X-ray irradiation, which is embedded in flat-panel X-ray imagers to create a detector. They are able to detect X-rays at a radiation dose 400 times lower than the existing medical diagnostics. The NUS Research team is working with display companies to commercialize the perovskite color-enhanced film.
Conventional scintillator detectors are produced using the solid-grow method. They can be produced only under high temperature. The fabrication of this scintillator is difficult compared to all other scintillators made from inorganic crystals. This disadvantage is overcome by the production of perovskite nanocrystals.
The discovered nanocrystals can detect and convert small doses of X-ray photons into visible light. They can also be tuned to light up in different colors in response to the X-rays they absorb. It is achieved by exploiting a novel concept called non-steady-state upconversion. Only 70 percent of the color is only visible to the human eye here. The color is turned by adjusting the pulse width and intensity of near-infrared laser excitation. With these properties, the nanocrystals could achieve higher resolution. The new technology is cheaper than the inorganic crystals used in traditional X-ray devices. In addition, the high-resolution images are obtained from a low dose of radiation. The cost of X-ray imaging can be decreased because of this invention.
X-ray images can be directly recorded using low-cost, digital cameras or even using cameras of mobile phones with the help of this technology. Using nanocrystals as scintillators, the cost of X-ray imaging is lowered. These nanocrystals can be produced using simpler, less expensive processes and at a relatively low temperature. The nanocrystals will be tested for longer times in order to validate the performance. It is tested under different temperatures and humidity levels. The fabrication is also straightforward.