A Novel Morpholine-Based Rhodamine Fluorescent Chemosensor For The Rapid Detection Of Hg2+ Ions

A novel rhodamine-based receptor bearing a morpholine (RDM) was developed as a fluorescent chemosensor with high selectivity toward Hg2+. After the addition of Hg2+ to RDM, the color of the solution changed from colorless to pink, and the new absorption band appears at 580 nm. The fluorescent of RDM appears to orange color in the presence of Hg2+. Upon the addition of Hg2+, ring-opening of the corresponding spirolactam gives rise to fluorescence, and a 1: 1 metal-ligand complex formed.