A glowing metal-free molecule could make MRI scans safer and sharper

Today's MRI contrast dyes rely on gadolinium, a metal with known side-effect risks. Ken Albrecht's team at Kyushu University in Japan has built two water-soluble molecules with no metal at all that pull double duty: they glow deep red under fluorescence imaging and sharpen MRI contrast 2.5 to 4.5 times better than previous metal-free attempts. In living cells, the molecules kept glowing around cell nuclei for more than 24 hours. Animal studies are next. Published in the journal Advanced Science.