A NIR fluorescent probe based on carbamoyl oxime with high specificity for detecting ferrous ions in food and in vivo.

Ferrous ions (Fe), the primary form of iron in cells, play a crucial role in various biological processes. The presence and absorption of Fe in food has an important impact on human health. Proper dietary intake and iron supplementation are conducive to prevent and treat iron-related diseases. Therefore, it is of great value to develop tools that can specifically and sensitively detect Fe in foods and organisms. Near-infrared (NIR) fluorescent probes have attracted much attention due to their advantages including deep tissue penetration and lower background fluorescence. Herein, a NIR fluorescent probe DICO-Fe(II) with a new recognition mechanism was constructed. DICO-Fe(II) achieves the highly specific recognition of Fe through its carbamoyl oxime recognition site and exhibits high sensitivity with a limit of detection of 47 nM. DICO-Fe(II) can quantitatively detect Fe with the naked eye through RGB values. It was also successfully applied to detect Fe in food samples, cells, zebrafish, and mice tissues, confirming its potential as a modern analytical tool for the detection of Fe in food and biological organisms.