Fluorescent Ratiometric Metal Ion Sensors

In a project to study new sensor methodologies for environmentally significant metals, we investigate the design, synthesis and speciation of nitrogen or sulfur-based ligands for copper, zinc, iron and other transition elements. The system we study engages aspects of coordination chemistry, fluorescence spectroscopy, and responsive polymers to create a generalized ratiometric sensor system. The cartoon below shows the mechanism of detection and readout:

We have developed a method for preparing high sensitivity fluorescent ratiometric indicators that is applicable to any metal ion species that can be complexed by a polymer-bound ligand.  To date our work has focused on Cu(II) because free Cu(II) is toxic to aquatic life and cannot be directly measured by existing methodology.

*We thank our collaborator Prof. W. Rudolf Seitz for important contributions.

Representative publication:

L.A. Fulton, W. Rudolf Seitz, R.P. Planalp, Aggregation of Poly(N-isopropylacrylamide) Homopolymer by Cu(II) and Zn(II): Significance for Ratiometric Metal Ion Indicators, Polyhedron, 191(2020) 114797.