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A simple thiocarbazone‐appended coumarin derivative 1 with high selectivity as a ratiometric fluorescence sensor towards Cu2+ and Zn2+ in a semi‐aqueous solution was synthesised and characterised. Upon the addition of Cu2+ and Zn2+, the emission of 1 solution undergoes a blue and red shift to 480 and 545 nm according to the intense blue and yellow colour under a 365‐nm ultraviolet lamp, respectively. Binding was confirmed by ultraviolet‐visible absorption analysis, fluorescence measurement, mass spectrometry, proton nuclear magnetic resonance, Fourier Transform‐infrared spectroscopy and density functional theory calculation. The results show that 1 coordinated with Cu2+ and Zn2+ in different modes, resulting in different ratiometric fluorescence responses. The detection limits of the sensor 1 for Cu2+ and Zn2+ were 100.8 and 11.5 nM, respectively. The association constants (Ka) of Cu2+ and Zn2+ with 1 were determined to be 5.59 × 104 and 5.08 × 104 M−1, respectively. Fluorescent microscopy experiments demonstrated that probe 1 has the potential to be used to monitor Zn2+ and Cu2+ in living cells. [ABSTRACT FROM AUTHOR]

A rhodamine-2-thioxoquinazolin-4-one derivative ( R1 ) has been synthesized by an addition-elimination reaction of rhodamine 6G ethylenediamine with methyl 2-isothiocyanatobenzoate, which exhibits high selectivity and sensitivity as a fluorescent sensor toward Fe 3+ under physiological conditions. Moreover, R1 could sense Fe 3+ by “naked eye” with a color change from colorless to yellow. To test the practical use of the probe, the determination of Fe 3+ in real water samples was evaluated. The application of the fluorescent sensor in monitoring intracellular Fe 3+ in glioma cell line U251 has also been demonstrated. In addition, single crystal structures of R1 ·1·5H 2 O·0·5CH 3 CN, as well as the possible intermediate of R1 with Ag + and Hg 2+ ions were reported. [ABSTRACT FROM AUTHOR]

A simple chemosensor, 6-(1H-pyrrol-2-yl)-5,6-dihydro-benzo[4,5]imidazo[1,2-c]quinazoline (1), was synthesized via simple nucleophilic addition reaction coupled with Schiff base condensation. The probe 1 is aggregation-induced emission-active and could be used as an on-off fluorescence sensor toward Cu 2+ in H 2 O/CH 3 CN (99.5%, v/v) solution. Furthermore, the resultant Cu 2+ complex selectively responded to pyrophosphate (PPi) among various anions based on fluorescent on-off signal. In addition, the probe could be used for detecting Cu 2+ and PPi in HeLa cells., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A new colorimetric and fluorescence molecular chemosensor based on triazole hydrazone can be used as a multi-probe for selective detection of Al 3+ , Zn 2+ , and Cu 2+ by monitoring changes in the absorption and fluorescence spectral patterns. Results show that Al 3+ and Zn 2+ ions can induce remarkable fluorescence enhancement at pH 6.0 and pH 10.0, respectively, while the addition of Cu 2+ ions leads to a significant UV-visible absorption enhancement in the visible range at pH 6.0. In addition, the resultant Al 3+ complex could act as an 'on-off' fluorescence sensor for F - . The fluorescence sensor was also used to monitor intracellular Al 3+ , Zn 2+ , and F - in Hela cells., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)