A new probe with high selectivity and sensitivity for detecting copper ions in traditional Chinese medicine and water sample

A new probe TR-V (Indolo[2,1–b]quinazoline-6,12-dione,6-{(6Z),(2′E)-2′- [(2-hydroxy-3-methoxyphenyl)methylene]hydra zinylidene}) based on tryptanthrin has been synthesized for selective and rapid detection of Cu 2+ . The synthetic route is facile, economical and viable. TR-V reacts in Tris-HCl buffer solution (pH = 8.0) with cupric to a deep yellow chelate which has a significant peak at 450 nm in the UV–Vis spectra. The reaction is instantaneous, ranging from light yellow to dark yellow and the change in color can be observed with the naked eye. Over 13 competitive metal ions do not interfere in the determination. The detection limit is 84 nM (R 2  = 0.9998). Thus, this method was selected for the analysis of copper ions in tap, bottled water and traditional Chinese medicine samples under optimized experimental conditions.