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Hydrazine (N2H4) is a highly toxic and harmful chemical reagent. Fluorescent probes are simple and efficient tools for sensitive monitoring of N2H4 enrichment in the environment, humans, animals, and plants. In this work, a ratiometric fluorescent probe (FP‐1) containing coumarin was used for hydrazine detection. The proposed FP‐1 probe had a linear detection range of 0–250 μM and a limit of detection (LOD) of 0.059 μM (1.89 ppb). A large red Stokes shift was observed in fluorescence and UV–vis absorption spectra due to the hydrolysis of ester bonds between FP‐1 and hydrazine. The hydrazine detection mechanism of FP‐1 was also investigated using density functional theory (DFT) calculations. Finally, FP‐1 could sensitively and selectively monitor hydrazine in actual water samples and BEAS‐2B cells. Therefore, it has great application potential in environmental monitoring and disease diagnosis. [ABSTRACT FROM AUTHOR]

A novel method was developed for studying the interaction between epirubicin hydrochloride (EPI) and bovine serum albumin (BSA) by fluorescence spectrometry. Fe3O4 magnetic nanoparticles (MNPs) synthesized and functionalized with thiol group were employed for the immobilization and separation of target BSA in reaction solutions. The concentrations of the non-immobilized BSA and unbound EPI were obtained separately by fluorescence spectrometry. The binding constants ( K a) and number of binding sites ( n) of EPI with BSA were calculated. In this study, the K a value was 5.05 × 105 L mol−1, suggesting a strong binding of EPI to BSA, and the n value was 1.15. The effects of common metal ions on K a of EPI with BSA were also investigated, and the results showed there was clearly bindings between the metal ions and BSA. The precise binding sites of EPI on BSA were determined as being in site I from the competitive displacement experiments. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Based on fluorescein, a novel water-soluble and reversible fluorescent probe (Flu-Py) was designed and synthesized for the sequentially “ON–OFF–ON” fluorescent detection of Al 3+ and F − in concentration range of 0–10 μmol L −1 and 0–30 μmol L −1 , respectively, with high sensitivity and excellent selectivity. The detection limits for Al 3+ and F − were 0.092 μmol L −1 and 0.112 μmol L −1 , respectively. The binding mode and sensing mechanism of Flu-Py with Al 3+ was verified by density functional theory (DFT) and time dependent density functional theory (TDDFT) calculation. The “ON-OFF–ON” fluorescent property of Flu-Py upon the addition of Al 3+ and F − was utilized for the imaging of living cells. [ABSTRACT FROM AUTHOR]

A new rhodamine derivative (RhS) with a recognition capability for Cu 2+ was synthesized and employed as a reversible fluorescent probe for Cu 2+ in drinking water and living cells. The spirolactam ring-opening of probe RhS induced by Cu 2+ lead to a highly selective fluorescence “turn-on” response toward Cu 2+ over other metal ions with micromolar sensitivity. The 1:1 stoichiometric structure between RhS and Cu 2+ were supported by Job's plot, MS and DFT theoretical calculations. The analytical results obtained by UV–vis and fluorescence spectrophotometry show that the linear range and the limit of detection (LOD) of the present probe for Cu 2+ are 0.50–20.00 and 0.11 μmol L −1 , respectively. The present probe was applied to the detection of Cu 2+ in drinking water with the recoveries ranging from 100.4 to 101.2%, and the fluorescence imaging for living HeLa cells. [ABSTRACT FROM AUTHOR]

A trivalent chromium (Cr 3 + ) fluorescence probe (RhC) was designed and synthesized via Schiff base reaction based on rhodamine–crown ether conjugate. This probe displayed a favorable selectivity for Cr 3 + over a range of other common metal ions in DMF/H 2 O (3:7, v / v ; PBS buffer 50 mmol L − 1 ; pH = 6.8) solution, leading to prominent fluorescence “OFF–ON” switching of the rhodamine fluorophore. The limit of detection was calculated to be 1.5 μmol L − 1 (S/N = 3). The binding ratio of RhC–Cr 3 + complex was determined to be 1:2 according to the Job's plot and HR-MS. The probe was successfully applied to examination of Cr 3 + in drinking water spiked samples. The average recoveries ranged from 104.9% to 106.9% at spiked concentration level of 10.00 μmol L − 1 , and the obtained results were consistent with those obtained using atomic absorption spectrometry (AAS). Moreover, bioimaging experiments showed that RhC can sense the Cr 3 + in living cells with a fluorescence enhancement signal. [ABSTRACT FROM AUTHOR]

In this article, a novel fluorescent probe (NRBE) for detecting H 2 O 2 was developed using benzyl boronic ester as the H 2 O 2 -recognized group and Nile red as the matrix. The probe has several advantages, such as good selectivity, high sensitivity (LOD = 75 nM), good water solubility and emission in the near-infrared region (ex/em:585/670 nm). With the NRBE probe, the endogenous H 2 O 2 in human hepatocellular carcinoma cells BEL-7402, was detected, and the H 2 O 2 generated during the ischemia-reperfusion of the cells was imaged. These results show that NRBE can be applied for real-time detection of H 2 O 2 in biological systems. Unlabelled Image • A novel Nile red-based fluorescent probe NRBE was designed and synthesized for H 2 O 2 detection. • The probe has good selectivity, high sensitivity, good water solubility and emission in the near-infrared region. • The probe can be applied for real-time detection of H 2 O 2 in biological systems. [ABSTRACT FROM AUTHOR]

A water-soluble fluorescence probe (TF) derived from fluorescein has been developed. This probe can be used to detect ClO − and Cd 2+ under physiological condition based on oxidation and coordination reactions, exhibiting almost 64-fold and 4-fold fluorescence enhancement. The experimentally observed changes in the structure and electronic properties of the probe in the presence of ClO − and Cd 2+ were modeled by density functional theory (DFT) and time-dependent density functional theory (TDDFT) computational calculations. Moreover, the present probe was successfully applied to the fluorescence imaging of ClO − and Cd 2+ in living cells. [ABSTRACT FROM AUTHOR]

Hydrazine (N 2 H 4 ) is a highly toxic and harmful chemical reagent. Fluorescent probes are simple and efficient tools for sensitive monitoring of N 2 H 4 enrichment in the environment, humans, animals, and plants. In this work, a ratiometric fluorescent probe (FP-1) containing coumarin was used for hydrazine detection. The proposed FP-1 probe had a linear detection range of 0-250 μM and a limit of detection (LOD) of 0.059 μM (1.89 ppb). A large red Stokes shift was observed in fluorescence and UV-vis absorption spectra due to the hydrolysis of ester bonds between FP-1 and hydrazine. The hydrazine detection mechanism of FP-1 was also investigated using density functional theory (DFT) calculations. Finally, FP-1 could sensitively and selectively monitor hydrazine in actual water samples and BEAS-2B cells. Therefore, it has great application potential in environmental monitoring and disease diagnosis., (© 2023 John Wiley & Sons Ltd.)

A novel method was developed for studying the interaction between epirubicin hydrochloride (EPI) and bovine serum albumin (BSA) by fluorescence spectrometry. Fe 3 O 4 magnetic nanoparticles (MNPs) synthesized and functionalized with thiol group were employed for the immobilization and separation of target BSA in reaction solutions. The concentrations of the non-immobilized BSA and unbound EPI were obtained separately by fluorescence spectrometry. The binding constants (K a ) and number of binding sites (n) of EPI with BSA were calculated. In this study, the K a value was 5.05 × 10 5  L mol -1 , suggesting a strong binding of EPI to BSA, and the n value was 1.15. The effects of common metal ions on K a of EPI with BSA were also investigated, and the results showed there was clearly bindings between the metal ions and BSA. The precise binding sites of EPI on BSA were determined as being in site I from the competitive displacement experiments. Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)