Coordination Chemistry of Anion Receptors and Sensing

Coordination chemistry of anion receptors exploits the tunable coordination sphere of metal centres to achieve selective anion recognition and quantification. By choosing appropriate metal ions—often transition metals such as ruthenium, iridium or palladium—and tailoring surrounding ligands, researchers can programme binding pockets that engage anions through hydrogen bonding, electrostatic interactions, halogen bonding or reversible covalent linkages. Such design principles allow modulation of affinity, selectivity and signal transduction pathways. Sensing modalities predominantly encompass optical responses, including colourimetric shifts and luminescence changes, as well as electrochemical outputs. Recent efforts have focused on enhancing water solubility and biocompatibility to enable in situ analysis in environmental and biological media. Applications span environmental monitoring of fluoride and phosphate, intracellular imaging of biologically relevant anions and integration into smart materials for real‐time process control. Advances in supramolecular and inorganic chemistry continue to refine receptor architectures, fostering sustainable sensors with high sensitivity and low detection limits.

Research from Nature Portfolio

Innovative work has explored chiral α,β-unsaturated ketone scaffolds as fluorescent probes for diverse anions. One series of compounds demonstrated exceptional sensitivity to dihydrogen phosphate, achieving recoveries above 98 % in fertiliser matrix testing. Spectroscopic analysis and theoretical modelling revealed that selective binding arises from reversible C=C-based hydrogen bonding within a chiral environment, affording both high affinity and enantioselective discrimination. Circular dichroism and molecular orbital studies elucidated the interplay between chirality and anion recognition, highlighting new routes towards stereoselective sensing platforms.

Coordination Chemistry of Anion Receptors and Sensing publication trend

The graph below shows the total number of articles in coordination chemistry of anion receptors and sensing across all publications each year (not limited to Nature Index journals).

Technical terms

Coordination sphere: The metal centre and its directly bonded ligands, defining geometry and chemical reactivity.

Anion receptor: A ligand or supramolecular assembly designed to bind anions selectively through non-covalent or reversible covalent interactions.

Colourimetric sensing: Detection method based on a visible colour change upon analyte binding.

Luminescent chemosensor: A sensor that emits light upon analyte interaction, often exploiting metal-centred photophysics.

Selectivity: The preference of a receptor for one analyte over others, determined by binding affinity and interaction geometry.

References

1. Development and Application of Ruthenium(II) and Iridium(III) Based Complexes for Anion Sensing. Molecules (2023).
2. Anion receptor chemistry: highlights from 2011 and 2012. Chemical Society Reviews (2014).
3. Potential chiral fluorescent molecular probes based on an α,β-unsaturated ketone for anion detection. Scientific Reports (2019).
4. Determination and Imaging of Small Biomolecules and Ions Using Ruthenium(II) Complex-Based Chemosensors. Topics in Current Chemistry (2022).
5. Colorimetric fluoride detection in dimethyl sulfoxide using a heteroleptic ruthenium( ii ) complex with amino and amide groups: X-ray crystallographic and spectroscopic analyses. RSC Advances (2022).