Novel polycyclic "turn-on" and "turn-off" pyrazoline and pyrazole fluorescent sensors for selective real-world monitoring of Fe3+/Fe2+ in aqueous environments

Seven novel polycyclic pyrazoline and pyrazole sensors were synthesised and screened for useful photophysical properties with pyrazoline 2 and pyrazole 7, displaying an Fe3+ "turn-off" response in aqueous environments with Fe3+ limits of detection (LoD) of 2.12 μM and 3.41 μM, respectively. Both 2 and 7 sensors functioned in aqueous environments with real-world examples of Fe3+ detection in tap water and mineral water samples. 2 and 7 are suitable for the detection of Fe3+ at concentrations below the maximum iron limits for drinking water set by the Environmental Protection Agency (EPA) and European Union (EU).

Erbium(III) complexes with fluoroquinolones: Structure and biological properties

Four erbium(III) complexes with the fluoroquinolones enrofloxacin, levofloxacin, flumequine and sparfloxacin as ligands were synthesized and characterized by a wide range of physicochemical and spectroscopic techniques as well as single-crystal X-ray crystallography. The compounds were evaluated for their activity against the bacterial strains Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Xanthomonas campestris, which was higher than that of the corresponding free quinolones. The interaction mode of the complexes with calf-thymus DNA is via intercalation, as suggested by diverse studies such as UV-vis spectroscopy, DNA-viscosity measurements and competitive studies with ethidium bromide. Fluorescence emission spectroscopy revealed the high affinity of the complexes for bovine and human serum albumin and the determined binding constants suggested a tight and reversible binding of the compounds with both albumins.

Synthesis, characterization, luminescence properties and deciphering the role of a terpyridyl-imidazole based ligand in the dissimilar luminescence sensitization of ternary lanthanide(III) tris-(β-diketonate) complexes

We designed four ternary lanthanide tris-(β-diketonate) complexes of the form [Ln(tta)3(tpy-HImzphen)], where Ln = LaIII, EuIII, SmIII and TbIII; tta = (2-theonyltrifluoroacetonate) and tpy-HImzphen = 2-(4-[2,2':6',2'']terpyridin-4'-yl-phenyl)-1H-phenanthro[9,10-d]imidazole. All the complexes have been thoroughly characterized by standard analytical tools and spectroscopic techniques including single crystal X-ray diffraction. In situ generation of the complexes was also monitored via absorption and emission spectroscopy upon incremental addition of the respective lanthanide precursor {Ln(tta)3(H2O)2} to the dichloromethane solution of the terpyridyl-imidazole ligand. The photophysical behaviors of all the complexes were thoroughly investigated via absorption and both steady-state and time-resolved emission spectroscopic techniques. The emission spectral measurements were carried out at both room temperature and 77 K to understand the deactivation dynamics of the excited states and elucidate the distinctive luminescence responses from the four lanthanide metal ions owing to the introduction of the terpyridyl-based ancillary ligand.

[ARTICLE WITHDRAWN] Preventive and Therapeutic Effect of Lanthanide Coordination Polymers on Severe Burn Infection by Inhibiting Staphylococcus epidermidis Infection

THIS ARTICLE WAS WITHDRAWN BY THE PUBLISHER IN SEPTEMBER 2022

Five Dinuclear Lanthanide Complexes Based on 2,4-dimethylbenzoic Acid and 5,5'-dimethy-2,2'-bipyridine: Crystal Structures, Thermal Behaviour and Luminescent Property

A series of new complexes, [Ln (2,4-DMBA)3(5,5'-DM-2,2'-bipy)]2 (Ln = Sm(1), Eu (2)), [Pr (2,4-DMBA)3 (5,5'-DM-2,2'-bipy)]2·0.5(C2H5OH) (3), [Ln (2,4-DMBA)3 (5,5'-DM-2,2'-bipy)]2·0.5(2,4-DMBAH)·0.25(5,5'-DM-2,2'-bipy) (Ln = Tb (4), Dy (5)) (2,4-DMBA = 2,4-dimethylbenzoate, 5,5'-DM-2,2'-bipy = 5,5'-dimethy-2,2'-bipyridine) were synthesized via hydrothermal reaction conditions. The complexes were characterized through elemental analysis, Infrared spectra (IR), Raman (R) spectra, UV-Vis spectra, single X-ray diffraction. Single crystal data show that complexes 1-5 are binuclear complexes, but they can be divided into three different crystal structures. The thermal decomposition mechanism of complexes 1-5 were investigated by the technology of simultaneous TG/DSC-FTIR. What's more, the luminescent properties of complexes 1-2 and 4 were discussed, and the luminescence lifetime (τ) of complexes 2 and 4 were calculated.

Eu(III)-coordination polymer: inhibitory activity on cervical cancer via inducing ROS mediated apoptosis

Under the hydrothermal reaction condition, we prepared a new 3D Eu(III)-based coordination polymer (CP) [Eu(H₂-DHBDC)_0.5(DHBDC)_0.5 (H₂O)₂] _n ·H₂O (1, H₄-DHBDC = 2,5-dihydroxy-1,4-terephthalic acid). Furthermore, we assessed the inhibitory influence on cervical cancer cells of this compound. First, for testing the anti-viability of the compound against cervical cancer cells, the cell counting kit-8 (CCK-8) assay was carried out. Then, reactive oxygen species (ROS) detection kit was used to determine the ROS accumulation in the cervical cancer cells. Finally, after the Annexin V-FITC/PI apoptosis assay was finished, it was used for apoptotic cervical cancer cells after treated with compound. From the results of the software of pose scoring and molecular docking, we can see that the compound may bind to p91 by the functional side-chain of the ligand, which provided potential regulatory mechanisms for the compound.

Photo-physical, theoretical and photo-cytotoxic evaluation of a new class of lanthanide(iii)–curcumin/diketone complexes for PDT application

Improved ISC in La(iii) complex of curcumin, on activation with visible light, has resulted in high yield of ¹O₂ in HeLa/MCF-7 cells, leading to the oxidative stress which was responsible for remarkable caspase 3/7-dependent apoptotic photocytotoxicity.