A phthalazine-based two-in-one chromogenic receptor for detecting Co²⁺and Cu²⁺in an aqueous environment

Abstract

A new multifunctional and highly selective chemosensor for Co(2+) and Cu(2+) was designed and synthesized. could simultaneously detect both Co(2+) and Cu(2+) by changing its color from pale yellow to pink and to orange in a near-perfect aqueous solution. The binding modes of to Co(2+) and Cu(2+) were determined to be a 2 : 1 complexation stoichiometry through Job's plot, ESI-mass spectrometry analysis and (1)H NMR titration. The detection limits (1.5 and 2.1 μM) of for Co(2+) and Cu(2+) were lower than the DEP guidelines (1.7 μM for Co(2+)) and the WHO guidelines (31.5 μM for Cu(2+)) for drinking water. The chemosensor could be used to quantify Co(2+) and Cu(2+) in water samples. Moreover, could be used as a practical, visible colorimetric test kit for both Co(2+) and Cu(2+). The sensing mechanisms of Co(2+) and Cu(2+) by were supported by theoretical calculations.

Colorimetric Co2+ sensor based on an anionic pyridylazo dye and a cationic polyelectrolyte in aqueous solution

“…). The K a value is in the range of those previously reported ( K a = 10 4 –10 22 ) for Co 2+ binding chemosensors …”

“…From k and σ (1.96 × 10 −3 ), the detection limit was calculated as 0.51 µmol L −1 , which is lower than the guideline (1.7 µmol L −1 ) recommended by the US Environmental Protection Agency (US EPA) . The detection limit was comparable to or lower than those (0.45–1.5 µmol L −1 ) of other colorimetric chemosensors for Co 2+ in aqueous solution . Thus, the 5‐Br‐PAPS and PDADMAC mixture is an excellent colorimetric chemosensor for the quantification of Co 2+ in aqueous solution.…”

“…37 The detection limit was comparable to or lower than those (0.45-1.5 μmol L −1 ) of other colorimetric chemosensors for Co 2+ in aqueous solution. [37][38][39][40] Thus, the 5-Br-PAPS and PDADMAC mixture is an excellent colorimetric chemosensor for the quantification of Co 2+ in aqueous solution.…”

A tricorn‐rhodamine fluorescent chemosensor for detection of Co2+ ions

“…There have been some chemosensors for Co 2+ ions with a detection limit at ca. 10 −6 M . Here, we report a highly sensitive and selective fluorescent probe for Co 2+ ions, TrisRh, a new rhodamine‐based compound, in which three rhodamine 6G unit are linked by tris(2‐aminoethyl)amine.…”

A highly sensitive benzimidazole-based chemosensor for the colorimetric detection of Fe(ii) and Fe(iii) and the fluorometric detection of Zn(ii) in aqueous media

“…[25][26][27][28][29][30][31] In particular, the development of chemosensors that can discriminate Zn 2+ from Cd 2+ is still a huge challenge as they are in the same group of the periodic table and have similar properties. [35][36][37][38][39][40][41][42] Benzimidazole derivatives provide a good possibility to chelation with transition metal ions, which displays excellent uorogenic properties. [35][36][37][38][39][40][41][42] Benzimidazole derivatives provide a good possibility to chelation with transition metal ions, which displays excellent uorogenic properties.…”