Turn-off detection of Cr(III) with chelation enhanced fluorescence quenching effect by a naphthyl hydrazone Shiff base chemosensor

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2022-11, Vol.281, p.121599, Article 121599
• Main Authors: Musikavanhu, Brian, Zhang, Yujie, Zhu, Dongwei, Xue, Zhaoli, Yuan, Rui, Wang, Shengjun, Zhao, Long
• Format: Article
• Language: English
• Subjects: Cell permeability; Chelation enhanced quenching; Cytotoxicity; Schiff base; Trivalent chromium
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2022.121599

[Display omitted] •An azine derivative turn-off fluorescence probe, NHT, is prepared for Cr3+ detection.•Chelation enhanced fluorescence quenching is validated as sensing mechanism.•NHT performs low detection limit, short time response and high selectivity towards Cr3+.•Low cytotoxicity and good PC3 cell permeability of NHT confirms its bioapplicable. A thiophene substituted naphthyl hydrazone derivative NHT was synthesized using a one-step route for the detection of trivalent chromium (Cr3+). UV–visible absorption and emission spectra, density functional theory calculations as well as 1H NMR titration confirmed that the probe underwent a turn-off response via the chelation enhanced fluorescence quenching effect upon exposure to Cr3+ and the NHT-Cr3+ complex was formed at a 1:1 binding stoichiometry. NHT exhibited a fast response rate of 2.3 min in buffer solution and a relatively low limit of detection of 41 nM. In addition, the Schiff base chemosensor exhibited excellent selectivity with high affinity towards Cr3+ in the presence of other competing cations. Bioimaging of the probe in PC3 cells further demonstrated the potential real life application of the probe in detecting Cr3+.