Researchers at Guangdong University of Petrochemical Technology have developed a fluorescent probe that shifts from red to green when it binds to uranyl ions, the mobile form of uranium found in contaminated water. The material, called EuZn-PMA, combines europium and zinc with pyromellitic acid. In lab tests it detected uranium down to 51 nanomolar and recovered 94.5% to 102.5% of added uranium in spiked lake water and seawater. A key point for field use is that the color shift can be read with a smartphone camera, so water testing may not require a lab spectrometer. The study appears in Sustainable Carbon Materials. The authors note more work is needed on naturally contaminated samples and mixed interfering substances before the probe is ready for real-world monitoring.
