A new 1, 8-naphthalimide-based fluorescent "turn-off" sensor for detecting Cu2+ and sensing mechanisms. Issue 1 (January 2020)

• Record Type: Journal Article
• Authors: Qu, Yao; Wu, Yancong; Wang, Cong; Zhao, Kun; Wu, Huilu
• Is Part Of: Journal of chemical research. Volume 44:Issue 1/2(2020)
• Page Start: 121
• Page End: 127
• Publication Date: 2020-01
• Subjects: 1, 8-naphthalimide -- CuII ions -- fluorescence sensor -- reverse photoinduced electron transfer -- Schiff base; Chemistry -- Research -- Periodicals; Chemistry -- Periodicals; 540.5
• DOI: 10.1177/1747519819886540
• Languages: English
• ISSNs: 1747-5198

Abstract

In this article, a new "turn-off" fluorescent sensor N - n -butyl-4-{2-[(ethylimino)methyl]phenol}-1, 8-naphthalimide (HL) for Cu II ions is synthesized, which contains a 1, 8-naphthalimide moiety as the fluorophore and a Schiff base as the recognition group. As expected, it exhibits high selectivity and sensitivity for detecting Cu II ions over other common metal ions in acetonitrile–2-(4-(2-hydroxyethyl)-1-piperazinyl)-ethanesulfonic acid (HEPES) (1:1 v/v, pH = 7.4) solution. In addition, the fluorescence intensity forHL showed a good linearity with the concentration of Cu II ions in the range of 0.5–5.0 μM. The 2:1 binding stoichiometry betweenHL and Cu II ions was established on the basis of combined fluorescence titrations, a Job's plot, single-crystal X-ray analysis and mass spectrometry. The quenching response ofHL toward Cu II ions is attributed to the reverse photoinduced electron transfer mechanism. The proposed sensorHL is preliminarily applied to quantify Cu II ions in water samples from the Yellow River and tap water.