A new fluorogenic mono-ionizable calix[4]arene dansylcarboxamide as a selective chemosensor of soft metal ions, Tl+ and Hg2+

Luminescent sensor for Cd2+, Hg2+ and Ag+ in water based on a sulphur‐containing receptor: quantitative binding–softness relationship

“…Such quenching is disadvantageous because it hampers a temporal separation of spectrally similar complexes with time-resolved fluorometry and because it produces lower output signal upon complexation. Moreover, among these literature findings, many researchers report water-soluble sensors for Hg 2+ (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19), but few report sensors in pure water for Ag + (19)(20)(21) and Cd 2+ (19,20,22,23). Although HTM ions are relatively easy to chelate and detect in organic solvents, they are rather difficult to recognize directly in aqueous environments, due to their strong hydration.…”

Dansyl-containing fluorogenic calixarenes as optical chemosensors of hazardous metal ions: a mini-review

“…Known metal-sensing dansyl-containing fluorogenic calixarenes (as well as thiacalixarenes) vary in the fashion of the fluorophore attachment to the receptor moiety as HN-dansyl (37,(41)(42)(43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54) and O-dansyl ligands (36,(55)(56)(57) (for the structural formulae, see Figures 1-4). In the former type, the anchor NH-group usually is a part of carbamoyl or aminoalkyl linker, or it may be bound directly to the aromatic ring of the calixarene; while in the latter type, the dansyl moiety is a substituent on the calixarene lower-rim phenolic oxygen.…”

“…A mono(N-dansylcarbamoyl)-containing calixarene 9 obtained in our group afterwards (49) was probed for sensing of hazardous metal ions in solvent extraction from aqueous solutions into CHCl 3 . It was discovered that with the aqueous-phase pH adjusted at 7.7 (borax buffer), in the presence of nearly 0.1 M Na þ , 9 provided selective recognition of microconcentrations of soft Tl þ .…”

A benzothiazole-based semisquarylium dye suitable for highly selective Hg2+ sensing in aqueous media

“…Despite the great efforts for the reduction of its industrial use, mercury pollution still continues through a variety of natural and anthropogenic sources [1][2][3]. To date, a number of Hg 2þ ion detection methods have been examined and include colorimetric strategies [4][5][6][7] and fluroionophores [3,[8][9][10][11]. We have previously reported the synthesis and metal ion detection properties of squarylium dyes [12][13][14] and have also described the aggregation properties of unsymmetrical squarylium dyes [15].…”