N₂S₂ pyridinophane-based fluorescent chemosensors for selective optical detection of Cd²⁺ in soils

Abstract

A fluorescent sensor array for the quantitative determination of Cd2+ in soils based on two N2S2 pyridinophane chemosensors is presented.

Recent Advances in Chemical Sensors for Soil Analysis: A Review

“…Combined together in the sensor array, the five cross-sensitive DCHQ-Ph-doped optodes performed better than when being used separately, and allowed a reduction in the RSD of magnesium determination in room plant fertilizers (down to 3.7% in comparison to the 5.5% for single optodes) and achieving an LDL of 4.6 × 10 −7 mol/L. Similarly, in [158] two N 2 S 2 pyridinophane-based fluorescent ligands were employed to form a cross-sensitive optical sensor array, which allowed quantitative determination of Cd 2+ in aqueous extracts from three soil samples with different anthropogenic influences: from beside a low-cost-flights runway (Ciampino G.B. Pastine Airport, Rome), from a university garden (Faculty of Science, "Tor Vergata" University, Rome), and from a dump site (Castello di Cisterna, Naples).…”

“…In recent work by our group, the two fluorescent chromophores obtained from the 2,8-dithia-5-aza-2,6-pyridinophane macrocycle substituted either with 2-(20-hydroxy-30naphthyl)-4-methylbenzoxazole (HNBO, ligand L1) or 7-(2-ethylamino)-4-methylcoumarin (ligand L2) were tested for the detection of Cd(II) and Zn 2+ ions in soils [158]. Ligands were incorporated inside PVC membranes, and optical sensors and a sensor array based on the photoassisted technique (PT) for sensing membrane luminescence were developed; see Figure 6.…”

“…The PT response of L1-and L2-based optodes in binary solutions of Cd 2+ and Zn 2+ ions, in 0.01 M HEPES buffer at pH 7.5 and LED illumination at λ ex = 380 nm. Reproduced from [158] with permission from the Centre National de la Recherche Scientifique (CNRS) and the Royal Society of Chemistry.…”

“…Recently, our research group has demonstrated the possibility of using arrays of optodes with PVC-based solvent polymeric membranes for improved assessments of Mg 2+ and Cd 2+ concentrations in fertilizers [117] and in soils [158]. Thus, through the inclusion of various ion-exchanger/ionophore ratios inside the optode sensing membranes, a series of novel, all-solid-state cross-sensitive sensors based on phenyl-substituted diaza-18-crown-6 8-hydroxyquinoline (DCHQ-Ph) was investigated in [117].…”

Selective and Sensitive Discrimination of Zinc and Cadmium Based on a Novel Fluorescent Porous Organic Polymer

“…However, these methods have their own limitations like tedious and time-consuming steps, requirements of professional operators, consuming a lot of reagents. Fluorescence methods with high sensitivity, rapidity and costsaving have become one of the best solutions to the above problems [12][13][14][15][16][17]. Until now, various fluorescence probe have been reported for Zn 2+ and Cd 2+ detection, such as naphthalimide-derived fluorophore [18], DNAzyme [19], quinoline derivatives [20,21], diarylethene derivatives [22], cephem-based probe [23] and dansyl-appended tetrapeptide [1].…”