Optical and quantitative detection of Ca2+ ion by an calix[4]arene-isophorone incorporated fluorometric and colorimetric probe

Calcium is the most common mineral in physiological fluids, aqueous environments, biomaterials, and the human body. Especially, it plays significant roles for biological activities in human life and therefore calcium determination in various environments is crucial. In the present study, a novel sensory macromolecule has been designed through the combining an isophorone unit with a calix[4]arene derivative for the recognition of Ca2+ ions. It has demonstrated distinct chromogenic and fluorogenic response towards Ca2+ ions in EtOH/H2O (v/v, 9/1, Tris-HCl buffer, pH 8.5). over other cations. It has ability to monitor selectively Ca2+ ions with slight chromogenic interference for Ba2+ and Sr2+ among 18 cations. The excellent sensing behavior has been further profited by a confirmation of concept studies such as the smartphone, cotton swab, yeast cells, logic gate operation to determine Ca2+ levels in tap and lake water samples.