Abstract
Two iron(III)-based molecular receptors employing 1,2-hydroxypyridinone ligands were developed for phosphate recognition and fluorescence sensing via indicator displacement assay (IDA). The tetra- and pentadentate ligands enable anion recognition by the iron(III) center via its remaining one or two open coordination sites. Weak protective coordination of fluorescein at those sites prevents the formation of μ-oxo dimers in aerated solutions. Its rapid and selective displacement by inorganic phosphate results in a 20-fold increase in the fluorescence of the indicator. Both receptors exhibit high affinity for inorganic phosphate and high selectivity over common competing anions, including halides, acetate, carbonate, and, remarkably, pyrophosphate as well as arsenate. Coordination of phosphate to the iron(III) center was confirmed by ATR-IR and 31P NMR spectroscopy.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1604-1609 |
| Number of pages | 6 |
| Journal | JACS Au |
| Volume | 2 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 25 2022 |
Bibliographical note
Funding Information:The authors acknowledge the support of the National Institutes of Health provided by R01 DK124333-01A1. S.-Y.H. was supported in part by a John Wertz Fellowship from the Department of Chemistry of the University of Minnesota and from a Doctoral Dissertation Fellowship from the University of Minnesota.
Publisher Copyright:
© 2022 American Chemical Society. All rights reserved.
Keywords
- fluorescence
- indicator displacement assay
- iron
- phosphate
- pyrophosphate
- supramolecular receptor