Fluorescent and luminescent probes for biological activity: A practical guide to technology for quantitative real-time analysis

Biological evaluation of rare earth complexes bearing 1H‐imidazo[4,5‐f]‐1,10‐phenanthroline moiety as promising anticancer chemotherapeutics

Lanthanum sulfadiazine (LaSD) was synthesized from sulfadiazine and lanthanum nitrate using water as solvent under alkaline conditions, and was used as a novel rare earth thermal stabilizer to stabilize poly(vinyl chloride) (PVC). The structure of LaSD was characterized by elemental analysis (EA), Fourier transform infrared spectroscopy (FTIR) and thermo- gravimetric analysis (TGA). The influence of lanthanum sulfadiazine with calcium stearate (CaSt₂) and epoxidized soybean oil (ESBO) on stabilizing PVC was studied by using the Congo red test, oven discoloration test, UV-vis spectroscopy and thermal decomposition kinetics. The results showed that the addition of LaSD as a thermal stabilizer can significantly improve the initial whiteness and long-term stability of PVC. In addition, the synergies between LaSD, ESBO, and CaSt₂ can provide outstanding improvement in the long-term thermal stability of PVC. When the ratio of LaSD/ESBO/CaSt₂ is 1.8/0.6/0.6, its thermal stability time is 2193 s which is the best state for stabilizing PVC. Furthermore, comparing the reaction energy (Ea) and the variations in the conjugate double bond concentration in PVC samples, the order of thermal stability of PVC was PVC/LaSD/ESBO/CaSt₂ > PVC/LaSD/ESBO > PVC/LaSD. The thermal stability mechanism of LaSD on PVC was studied by the AgCl precipitation method and FTIR spectrum. The results showed that the action of LaSD on PVC was achieved through replacing unstable chlorine atoms and absorbing hydrogen chloride.

Development and Investigation of Lanthanum Sulfadiazine with Calcium Stearate and Epoxidised Soyabean Oil as Complex Thermal Stabilizers for Stabilizing Poly(vinyl chloride).

https://www.tandfonline.com/doi/pdf/10.1080/16583655.2018.1516028

Synthesis, characterizations and photo-physical properties of novel lanthanum(III) complexes

Lanthanides such as cerium(III), europium(III), and gadolinium(III) are widely used for designing fluorescent probes or magnetic resonance imaging contrasting agents for biological systems. The synthesis and study of lanthanide complexes in buffer solutions imitating biological fluids are often complicated because of a lack of data on the lanthanide interactions with buffer solution components. Therefore, Ln(III) [where Ln(III) = La(III), Ce(III), Gd(III), Eu(III)] complexation with a widely used buffer agent, tris(hydroxymethyl)aminomethane (Tris), in aqueous solution is studied using potentiometry, spectrofluorimetry, and 139La NMR spectroscopy. The stoichiometric composition of complexes is determined using mass spectrometry. The thermodynamic stability constants of Ln(III)-Tris complexes are calculated from potentiometric and spectral data; the difficulties in the study of these systems, reliability, and accuracy of the obtained constants are discussed. The possible structures of free Tris and its complexes with lanthanides(III) are optimized on the density functional theory/PBE0 level; the peculiarities of metal-ligand bonds were studied by Quantum Theory Atoms in Molecules analysis.

La(III), Ce(III), Gd(III), and Eu(III) Complexation with Tris(hydroxymethyl)aminomethane in Aqueous Solution.

Praseodymium forms complexes easily with nitrogen and oxygen donor pyrazolines and also forms mixed ligand complexes with these pyrazolines and sulfur donor thio ligands such as dithiocarbamates and xanthates. These newly synthesized complexes have been characterized using elemental analysis, FTIR, TGA, SEM, TEM, PXRD and UV-visible spectral measurements. The isotopic studies were performed using DART mass spectrometry. The luminescent properties of these types of complexes were studied using a fluorescence spectrophotometer. The antimicrobial behavior of these praseodymium complexes was studied thoroughly during the present research.

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A study on enhancing the quantum yield and antimicrobial activity of Pr(III) by varying the coordination environment

Luminescent, optical, magnetic and metamaterial behavior of cerium complexes

The neodymium complexes with nitrogen and oxygen donor pyrazoline ligands were synthesized by the conventional method. To observe the effect of the change in environment, the mixed ligand complexes along with pure neodymium-pyrazoline complexes were synthesized. Shelf-life of these newly synthesized materials was studied by the absorbance spectral peaks, whereby the aging effect was clearly seen in all these neodymium complexes. Considering the effect of time and shelf-life, the neodymium-pyrazoline complexes show comparatively lower stability than the mixed ligand complexes of neodymium. The detailed characteristics of these newly synthesized materials are presented in this manuscript.

Aging effect on bonding properties of fluorescent neodymium materials

The indole oligomers were synthesized by an effective green route in the water medium. This is an effort to synthesize commercially important indole oligomers without using any harmful chemicals and artificial media. The lanthanide chlorides such as LaCl3·7H2O, CeCl3·7H2O, PrCl3·6H2O and NdCl3·6H2O were used in the synthesis procedure to minimize the reaction time. Unlike the previous works, these reactions occurred at somewhat elevated temperature. In the reaction, the salts of lanthanide metals acted as a catalyst and further behave as dopants. These dopants increased the various properties (like conducting behavior) of the oligomers. The synthesized hetero-oligomers were characterized by different physicochemical and spectral techniques. The luminescence phenomenon was studied by the absorbance, excitation and emission peaks, justifying the upconversion phenomenon. The conducting behavior of these oligomers was studied at different concentrations to observe the dependence of the conduction of electrons at various concentrations. In this manuscript, we first time introduced the LnCl3·xH2O to observe their behavior towards the reaction procedure, their doping behavior and the morphology of the synthesized oligomer particles. This study is an effort to synthesize the valuable indole oligomer via a more convenient way, which can be applicable in the field of luminescence, conductance, etc.

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Iffat Ameen

Papers

A study on enhancing the quantum yield and antimicrobial activity of Pr(III) by varying the coordination environment

Synthesis, characterizations and photo-physical properties of novel lanthanum(III) complexes

Luminescent, optical, magnetic and metamaterial behavior of cerium complexes

Aging effect on bonding properties of fluorescent neodymium materials

Photo-physical properties of lanthanides doped O-bridged conducting indole oligomer