A New pH-Dependent Macrocyclic Rhodamine B-Based Fluorescent Probe for Copper Detection in White Wine

For efficiently measuring copper (II) ions in the acidic media of white wine, a new chemosensor based on rhodamine B coupled to a tetraazamacrocyclic ring (13aneN(4)CH(2)NH(2)) was designed and synthesized by a one-pot reaction using ethanol as a green solvent. The obtained chemosensor was characterized via NMR, UV and fluorescent spectra. It was marked with no color emission under neutral pH conditions, with a pink color emission under acidic conditions, and a magenta color emission under acidic conditions where copper (II) ions were present. The sensitivity towards copper (II) ions was tested and verified over Ca(2+), Ag(+), Zn(2+), Mg(2+), Co(2+), Ni(2+), Fe(2+), Pb(2+), Cd(2+), Fe(3+), and Mn(2+), with a detection limit of 4.38 [Formula: see text] 10(−8) M in the fluorescence spectrum.