A colorimetric chemosensor for selective detection of copper ions

Abstract

A water‐applicable hexamethylbenzene (HMB) chemosensor, (E)‐2‐((2‐hydroxy‐3‐methoxybenzylidene)amino)benzamide, displayed a selective colour change from colourless to yellow in the existence of copper ions. The detection limit was computed as 1.57 μmol/L, which is substantially lower than the World Health Organisation guideline (31.5 μmol/L) for copper ions. Probe HMB could also sense and quantify copper ions in real water samples. The coordination mode of HMB to copper ions was demonstrated through Job plot, electrospray ionisation mass spectroscopy and proton nuclear magnetic resonance titration, and was also supported by theoretical studies.

A selective chromone‐based colorimetric chemosensor for detecting Cu2+ in near‐perfect aqueous solution and test kit

“…From the UV–visible titrations, the association constants for the first and second steps ( K ) were estimated to be 5.7 × 10 4 M −1 and 2.4 × 10 5 M −1 , respectively, using the Benesi–Hildebrand (Figure S5) [44]. The K value is within the scope (10 3 –10 12 ) formerly shown for copper‐ion sensors [45]. Detection limit of CMF for copper ion was given to be 0.38 μM, based on the 3σ/slope (Figure 3) [46].…”

A New Chromone‐based Sequential Functioning Colorimetric Chemosensor for Cu2+ and Cysteine in Near‐perfect Aqueous Media

“…However, these methods have problems of low sensitivity, high‐priced equipment, and complicated analysis [7–11] . Meanwhile, optical detection methods like colorimetry have the advantages of being simple, sensitive, and cheap through immediate color variations [10,12–19] . For those reasons, it is needed to develop colorimetry sensors to simply detect metals or amino acids [20–23] …”

“…[7][8][9][10][11] Meanwhile, optical detection methods like colorimetry have the advantages of being simple, sensitive, and cheap through immediate color variations. [10,[12][13][14][15][16][17][18][19] For those reasons, it is needed to develop colorimetry sensors to simply detect metals or amino acids. [20][21][22][23] Copper is essential for physiological body functions like mitochondrial electron transfer, neurotransmission process, melanin production, and bone formation.…”

An effective colorimetric sensor for detecting Cu2+ based on benzothiazole moiety

“…Herein, we illustrate a colorimetric sensor HMD for Cu 2+ , which could be readily synthesised by condensation of benzothiazole and salicylaldehyde moieties. The sensor HMD showed both a large bathochromic shift (152 nm) and a definite colour change for Cu 2+ 38,39 . The practical utilisation of HMD was deemed highly practical in that test strips could be applied at low concentration among copper‐selective colorimetric chemosensors based on the benzothiazole moiety 40‐42 .…”