Colorimetric Test Kit for Cu²⁺ Detection

Abstract

A coumarin-based colorimetric chemosensor 1 was designed and synthesized. It exhibits good sensitivity and selectivity for the copper cation over other cations such as Zn(2+), Cd(2+), Pb(2+), Co(2+), Fe(2+), Ni(2+), Ag(+), and alkali and alkaline earth metal cations both in aqueous solution and on paper-made test kits. The change in color is very easily observed by the naked eye in the presence of Cu(2+) cation, whereas other metal cations do not induce such a change. The quantitative detection of Cu(2+) was preliminarily examined.

Facile iron(III) chloride hexahydrate catalyzed synthesis of coumarins

“…[5][6][7][8][9][10][11][12] Apart from their pharmaceutical applications, [13][14] coumarins have been used as additives in foods, perfumes and cosmetics as well as in the preparation of optical brighteners, laser dyes, fluorescent labels and nonlinear optical chromophores. [15][16][17][18][19] The Pechmann reaction 20 is known as one of the most valuable methods for the synthesis of coumarins since it proceeds from simple starting materials, a phenol and a -keto ester, together with an acid catalyst. Various protocols have been developed by using different catalysts including sulfuric acid, 20 trifluoroacetic acid, 21 phosphorus pentaoxide, 22 aluminium chloride, [23][24] indium(III) chloride, 25 titanium(IV) chloride, 26 silica gel supported zirconyl chloride octahydrate, 27 samarium(III) nitrate hexahydrate, 28 bismuth(III) nitrate pentahydrate, 29 ionic liquids 30 and many more.…”

A highly selective “ON–OFF” probe for colorimetric and fluorometric sensing of Cu2+in water

“…A considerable number of uorescence based chemosensors have been reported for Cu 2+ in the past few years. [49][50][51][52][53][54][55] However, a couple of them possess disadvantages such as complicated synthetic procedures, unimpressive detection limit, use of organic solvents and interference from other associated metal ions. 46,54,[56][57][58] Most of the techniques for accurate and selective detection of Cu 2+ are based on chemosensors that undergo a uorescence intensity quenching (turn-OFF) in presence of analyte.…”

Simultaneous Production and Surface Functionalization of Silver Nanoparticles for Label-free Colorimetric Detection of Copper Ion

“…1,2 This is because Cu 2+ ion plays a major role in various metabolic pathways, [3][4][5] and excess uptake of Cu 2+ can build up in the kidneys, brain, and eyes to cause neurological problems, liver failure or kidney dysfunction. [6][7][8] Due to its important role, a large number of methods have been developed for the quantitative determination of metal ions in aqueous solution, [9][10][11] such as electrochemical methods, 12 chromatography-based methods, 13,14 microfluidic devices, 15 and spectroscopic methods. [16][17][18] However, most of the above methods require expensive equipment or complicated detection procedures, as well as the usage of environmentally unfriendly organic solvents.…”