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Abstract: In the present paper, we describe the fabrication and analytical characteristics of fluorescence-based zinc ion-sensing glass slides. To construct the sensor, a benzoxazole derivative 4-benzoxazol-2′-yl-3-hydroxyphenyl allyl ether (1) with a terminal double bond was synthesized and copolymerized with 2-hydroxyethyl methacrylate (HEMA) on the activated surface of glass slides by UV irradiation. In the absence of Zn2+ at pH 7.24, the resulting optical sensor emitted fluorescence at 450nm via excited-state intramolecular proton transfer (ESIPT). Upon binding with Zn2+, the ESIPT process was inhibited resulting in a 46nm blue-shift of fluorescence emission. Thus, the proposed sensor can behave as a ratiometric fluorescent sensor for the selective detection of Zn2+. In addition, the sensor shows nice selectivity, good reproducibility and fast response time. Cd2+ did not interfere with Zn2+ sensing. The sensing membrane demonstrates a good stability with a lifetime of at least 3 months. The linear response range covers a concentration range of Zn2+ from 8.0×10−5 to 4.0×10−3 mol/L and the detection limit is 4.0×10−5 mol/L. The determination of Zn2+ in both tap and river water samples shows satisfactory results. [Copyright &y& Elsevier]

Abstract: N-Methyl-α,β,γ,δ-tetraphenylporphine (NMTPPH) has been used to detect trace amount of zinc ions in ethanol–water solution by fluorescence spectroscopy. The fluorescent probe undergoes a fluorescent emission intensity enhancement upon binding to zinc ions in EtOH/H2O (1:1, v/v) solution. The fluorescence enhancement of NMTPPH is attributed to the 1:1 complex formation between NMTPPH and Zn(II) which has been utilized as the basis for the selective detection of Zn(II). The linear response range covers a concentration range of Zn(II) from 5.0×10−7 to 1.0×10−5 mol/L and the detection limit is 1.5×10−7 mol/L. The fluorescent probe exhibits high selectivity over other common metal ions except for Cu(II). [Copyright &y& Elsevier]

[Display omitted] • A Golgi-targetable fluorescent probe for hypochlorous acid has been reported. • The probe displays high sensitivity and high selectivity for HOCl. • The probe can be used for detection of HOCl within the Golgi apparatus of living cells. The Golgi apparatus (GA) is a vital organelle in biological systems and excess reactive oxygen species (ROS) is produced during stress in the Golgi apparatus. Hypochlorous acid (HOCl) is a significant reactive oxygen species and has strong oxidative and antibacterial activity, but excessive secretion of hypochlorous acid can affect Golgi structure or function abnormally, it will lead to a series of diseases including Alzheimer's disease, neurodegenerative diseases, autoimmune diseases, and Parkinson's disease. In present work, a novel fluorescent probe for Golgi localization utilizing naphthalimide derivatives was constructed to detect hypochlorous acid. The fluorescent probe used a derivatived 1,8-naphthalimide as the emitting fluorescence group, phenylsulfonamide as the localization group and dimethylthiocarbamate as the sensing unit. When HOCl was absent, the intramolecular charge transfer (ICT) process of the developed probe was hindered and the probe exhibited a weak fluorescence. When HOCl was present, the ICT process occurred and the probe showed strong green fluorescence. When the HOCl concentration was altered from 5.0 × 10−7 to 1.0 × 10−5 mol·L-1, the fluorescence intensity of the probe well linearly correlated with the HOCl concentration. The detection limit of 5.7 × 10−8 mol·L-1 was obtained for HOCl. The HOCl fluorescent probe possessed a rapid reaction time, a high selectivity and a broad working pH scope. In addition, the probe possessed good biocompatibility and had been magnificently employed to image Golgi HOCl in Hela cells. These characteristics of the probe demonstrated its ability to be used for sensing endogenous and exogenous hypochlorous acids within the Golgi apparatus of living cells. [ABSTRACT FROM AUTHOR]

Highlights: [•] A fluorescence-based ferric ion-sensing glass slides were described. [•] A naphthalimide derivative was photo-copolymerized on the surface of glass slides. [•] The Fe3+ sensor shows high selectivity in 100% aqueous solution. [•] The sensor exhibits sufficient repeatability, rapid response and long lifetime. [ABSTRACT FROM AUTHOR]