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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 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]

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.)