Search

[Display omitted] • A simple developed fluorescent probe was synthesized for rapid detection of CN– in colorimetric and fluorometric signal channels. • The crystal structure of the probe is reported. • The probe works in DMSO/HEPES (3:7, v/v) solution with large fluorescent emission (595 nm) and large Stokes shifts (145 nm). • The probe has been successfully applied to the imaging of CN− in C6 cells. In this work, a novel probe R was synthesized via Knoevenagel reaction between 3 H -benzo[ f ]chromium-2-formaldehyde and ethyl cyanoacetate for selective detection of CN– in both colorimetric and fluorescent signal channels. The recognition of CN– was through the nucleophilic reaction of CN– to C = C of probe R , which destroys π-conjugation and blocks the ICT effect of the probe, resulting in colorimetric and fluorometric responses. Probe R showed great sensitivity toward CN–, with large fluorescent emission (595 nm) and low detection limit (0.70 μM). Moreover, probe R can detect exogenous CN– 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 pyrazine-containing hydrazone sensor for Al3+ has been developed. • The crystal structure of 1, 1-Cu and 1-Ni have been reported. • The reluctant Al3+ complex of the sensor could recognize F− among various anions. • The sensor could be utilized to detect exogenous Al3+ and F− in HeLa cells. The hydrazone sensor (1) derived from pyrazine-2-carbohydrazide and 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was applied to the fluorescent "turn-on" detection of Al3+ in semi-aqueous solutions. The strongly emissive 1 +Al3+ complex could identify F− among other tested anions. The detection limits of sensor 1 for Al3+ and F− were 0.18 and 0.20 μM, respectively, which are both much lower than the corresponding values recommended by the World Health Organization, namely, 7.41 and 79 μM. Several spectral methods, including single crystal X-ray analysis for the crystal structures of the Cu2+ and Ni2+ complexes of sensor 1 , as well as the density-functional theory method, were used to elucidate the binding mode between the sensor and Al3+. 1 can also be used for a selective sensor to continuously monitor Al3+ and F− in living cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Carboxylesterases (CEs) are widely distributed in the body and catalyze the hydrolysis of endogenous and exogenous substrates. They play important roles in drug metabolism, and abnormal levels often result in numerous diseases such as cancers. Therefore, it is important to establish a highly selective and sensitive probe for the real-time sensing of CEs activity. Herein, we synthesized a novel fluorescence-electrochemical multichannel probe 1 containing a ferrocene unit, which not only serves as part of the structure of probe 1 but also provides electrochemical signals. The probe exhibited high selectivity to CEs with a "Turn-On" fluorescence response and was applied for imaging in complicated biological samples including Staphylococcus aureus , living cells, and zebrafish. Furthermore, the hydrolysis of the acetoxy group of probe 1 by CEs decreased the electrochemical signal. All these results suggest that probe 1 can act as a multi-modal probe for real-time tracking of the activity CEs in complex biological environments. • A ferrocene-chalcone-based probe for detecting CEs by fluorescence and electrochemical signals was developed. • Probe 1 exhibited rapid response, good optical performance, high selectivity, and high sensitivity in solution. • The crystal structure of probe 1 and product 1a were determined. • Endogenous imaging-based CEs-detection in a range of S. aureus species, C6 cells, and zebrafish was achieved. [ABSTRACT FROM AUTHOR]

Two novel Cu(II) complexes, [Cu(L) 2 (CH 3 OH)]·CH 3 OH ( 1 ) and [Cu(L)(DMF)Cl] ( 2 ) based on HL (where HL = 2-ethoxycarbonyl-5-formyl-3,4-dimethylpyrrole 4-hydroxylbenzoylhydrazone) were synthesized and characterized by X-ray diffraction analyses. The results show that in each complex, the acylhydrazone ligand is deprotonated and coordinated to the copper(II) ion via enolizated oxygen and imine nitrogen atoms. The central metal ion possesses a distorted square pyramidal and a square-planar coordination geometry in complexes 1 and 2 , respectively. In addition, complex 2 shows obvious inhibitory effect to bacterial strains Staphylococcus aureus and Salmonella typhimurium , and complex 1 has excellent antitumor activity towards Hepatocellular carcinoma (Hep G2) cells ( IC 50 = 2.0 μM). [ABSTRACT FROM AUTHOR]

• A simple benzo[ h ]chromene-based probe toward HSO 3 − has been developed. • The crystal structure of the probe is reported. • The probe is aggregation-induced ratiometric emission active. • The probe responses HSO 3 − in almost pure aqueous solution. • The probe could be utilized to detect exogenous HSO 3 − in HeLa cells. Monitoring levels of SO 2 and its derivatives, including sulfite (SO 3 2−) and bisulfite (HSO 3 −) ions, in biological systems is of great importance because their aberrant concentrations in cells may cause several diseases. Aggregation-induced-emission (AIE) active probes are exhibited good photophysical properties in aqueous solution, and have been applied in many fields. Herein, we report benzo[ h ]chromene aldehyde (1) with aggregation-induced ratiometric emission (AIRE) that showed a blue emission in a solution, whereas in an aggregate state, a green emission with 43-nm Stocks shift was observed. Furthermore, this green AIRE was specifically quenched using HSO 3 − under physiological conditions owing to the formation of a water-soluble and non-emissive product after the addition of bisulfite to the aldehyde group of 1. Finally, the imaging experiments indicated that probe 1 could be utilized to detect exogenous HSO 3 − in HeLa cells. [ABSTRACT FROM AUTHOR]

Five complexes, [Cu(L) 2 ]·4.5H 2 O ( 1 ), [Cu(HL) 2 ](NO 3 ) 2 ·CH 3 OH ( 2 ) {[Cu 2 (L) 2 (NO 3 )(H 2 O) 2 ]·(NO 3 )} n ( 3 ), [Cu 2 (HL) 2 (SO 4 ) 2 ]·2CH 3 OH ( 4 ) and [Cu 4 (L) 4 Cl 4 ]·5H 2 O ( 5 ) based on HL (where HL = 2-acetylpyrazine isonicotinoyl hydrazone) have been synthesized and characterized by X-ray diffraction analyses. The counter anion and organic base during the synthesis procedure influence the structures of the complexes efficiently, which generate five complexes as mono-, bi-, tetra-nuclear and one-dimensional structures. The antitumor activities of the complexes 1 – 5 (except for complex 3 with the poor solubility) against the Patu8988 human pancreatic cancer, ECA109 human esophagus cancer and SGC7901 human gastric cancer cell lines are screened by MTT assay. The results indicate that the chelation of Cu(II) with the ligand is responsible for the observed high cytotoxicity of the copper(II) complexes and the 1:2 copper species 1 and 2 demonstrate lower antitumor activities than that of the 1:1 copper species 4 and 5 . In addition, the in vitro apoptosis inducing activity of the copper(II) complex 5 against SGC7901 cell line is determined. And the results show that the complex can bring about apoptosis of the cancerous cells in vitro . [ABSTRACT FROM AUTHOR]

Abstract: NiO nanospheres have been synthesized by using magnetic stirring and ultrasound methods. The structure and morphology of synthesized samples were characterized by X-ray diffraction, scanning electron microscopy and high resolution transmission electron microscopy. The results show the NiO nanospheres prepared by the ultrasonic method are far less than that prepared by the stirring method. Moreover, in the presence of surfactant, the average diameter of NiO nanospheres prepared by the ultrasonic method is only 1–3nm. The capacitance of NiO electrodes was investigated with cyclic voltammetry. The NiO prepared by the ultrasonic method exhibited higher specific capacitance of ~260Fg−1 at 1Ag−1 current density. [Copyright &y& Elsevier]

Abstract: Three new ternary copper(II) complexes, [Cu2(phen)2(PDIMAla)(H2O)2](ClO4)2·CH3OH (1), [Cu2(dpq)2(PDIMAla)(H2O)2](ClO4)2·CH3OH (2) and [Cu2(dppq)2(PDIMAla)(H2O)2](ClO4)2·CH3OH (3) (phen=1,10-phenanthroline, dpq=dipyrido[3,2:2′,3′-f]quinoxaline, dppz=dipyrido[3,2-a:2′,3′-c]phenazine, H2PDIMAla= N,N′-(p-xylylene)di-alanine acid) have been synthesized and the complex 1 has been structurally characterized by single-crystal X-ray crystallography, spectrometric titrations, ethidium bromide displacement experiments, CD (circular dichroism) spectral analysis and viscosity measurements. The results indicate that the three compounds, especially the complex 3, can strongly bind to calf-thymus DNA (CT–DNA). The intrinsic binding constants K b of the ternary copper(II) complexes with CT–DNA are 0.38×105, 1.4×105 and 7.8×105 for 1, 2 and 3, respectively. Comparative cytotoxic activities of the copper(II) complexes are also determined by acid phosphatase assay. The results show that the ternary copper(II) complexes have significant cytotoxic activity against the human hepatic (HepG2), human promyelocytic leukemia (HL60) and human prostate (PC3) cell lines. Investigation of antioxidation property show that all the copper(II) complexes have strong scavenging effects for hydroxyl radicals. [Copyright &y& Elsevier]

Three novel complexes, [Cu 4 (L) 4 Cl 4 ]·H 2 O ( 1 ), Zn(L) 2 ( 2 ) and Cd(L) 2 ( 3 ), based on HL (where HL = 2-acetylpyridine isonicotinohydrazone) were synthesized and characterized by X-ray diffraction analyses. In the tetranuclear complex 1 , each copper(II) ion with a distorted square-planar coordination geometry is five-coordinated by one chloride anion, one ON 2 donor set and one 4-pyridine nitrogen atom from another adjacent actylhydrazone ligand. However, the central ions in complexes 2 and 3 possess distorted octahedral coordination geometry, surrounded by two ON 2 donor sets. In addition, all the complexes have excellent antitumor activity towards human lung cancer (A549) and human gastric cancer (SGC7901 and BGC823) cell lines. Furthermore, cell apoptosis induced by complex 1 was detected through TUNEL and Annexin V/PI staining with flow cytometric analysis and western blotting analysis. [ABSTRACT FROM AUTHOR]

A quinoline-based hydrazone, namely, bis((quinolin-8-yl)methylene)carbonohydrazide (1), has been designed and synthesized, which could be used as a dual probe for selective recognition of Co2+ and Zn2+ by monitoring changes in absorption and fluorescence spectral pattern, respectively. The detection limits of 1 for these two ions are 0.21 and 0.66 μM, respectively. The complex formation between 1 and Co2+/Zn2+ is responsible for the detection process, as confirmed through several spectral methods and DFT calculations. The application of the as-synthesized sensor is demonstrated in Zn2+ imaging in living cells. Unlabelled Image • A bis-hydrazone sensor bearing quinoline moiety has been developed. • The sensor could detect Zn2+ in semi-aqueous solution based on turn-on fluorescent signal. • The sensor acts as a colorimetric probe toward Co2+. • The crystal structures of the probe and its Zn2+ complex are reported. • The sensor has been used for imaging of Zn2+ in living cells. [ABSTRACT FROM AUTHOR]