Synthesis and effect of a new Terbium gibberellic complex on the histopathological alteration induced by Gibberellic acid on liver and kidney of mice Mus musculus.

The objective of this study was to synthesize Gibberellic lanthanide complex and evaluate its biological activity to reduce the Gibberellic acid toxicity on liver and kidney. The new bis(Gibberellic)-nitro-terbium(III) complex was characterized by different analytical methods: elemental analyses, UV-Vis, molar ratio, fluorescence, FT-IR, and TGA-DTA measurements. Thirty newborns were classified into three groups control, Gibberellic acid, and Terbium gibberellic acid complex. Livers and kidneys of studied groups proceed for general histology and immunohistochemical staining of Cyr61, cytochrome C, and TNFR2. From the absorption titration measurements, the binding constants of DNA with Tb(III)-(GA)2 complex and free ligand were found to be 3.9 × 104 and 2.1 × 103  m-1 , respectively, with the stoichiometry of 1:1. Hypochromism was observed from the absorption titration experiment which indicates the intercalation of Tb(III)-(GA)2 complex between the base pairs of DNA. Gibberellic acid-treated group showed alteration in the histological picture of livers and kidneys that accompanied with the reduction in the expression of Cyr61, cyt C, and TNFR2. The amelioration was observed in Gibberellic acid complex with Terbium group. The study concluded that Terbium gibberellic complex is less dangerous effects than Gibberellic acid alone.

Fluorescence sensing of phosdrin pesticide by the luminescent Eu(III)- and Tb(III)-bis(coumarin-3-carboxylic acid) probes.

Luminescence quenching of the Eu(III)- and Tb(III)-bis (coumarin-3-carboxylic acid) (Ln(III)-(CCA)2) probes has been studied in the presence of organophosphorus or organochlorine pesticides; Phosdrin (P1), Malathion (P2), Profenofos (P3), Formothion (P4), Heptachlor (P5), and Endosulfan (P6). The luminescence intensity of lanthanide complex probes Ln(III)-(CCA)2 decreases as the concentration of the Phosdrin pesticide increases, while the other investigated pesticides have no significant influence on the lanthanide fluorescent intensities. It is observed that the quenching of Eu(III) and Tb(III)-coumarin-3-carboxylic acid by Phosdrin proceeds via static quenching processes according to Stern-Volmer plot. The binding constants (K) and the thermodynamic parameters of the interaction of Ln(III)-(CCA)2 with Phosdrin have been determined. A direct method for the determination of the Phosdrin in ethanol has been developed based on the luminescence changes of the Ln(III)-(CCA)2-phosdrin ternary complexes. The detection limits of P1 were 6.28 and 1.07 µM in case of Eu(III) and Tb(III)-complex, respectively. The influence of various interfering species on the detection of P1 has been investigated to assess the analytical applicability of the method. The new method was applied to determine the Phosdrin pesticide in different types of water samples.

Groundwater quality and hydrochemical properties of Al-Ula Region, Saudi Arabia.

Groundwater quality monitoring is one of the most important aspects in groundwater studies in arid environments particularly in developing countries, like Saudi Arabia, due to the fast population growth and the expansion of irrigated agriculture and industrial uses. Groundwater samples have been collected from eight locations in Al-Ula in Saudi Arabia during June 2012 and January 2013 in order to investigate the hydrochemical characteristics and the groundwater quality and to understand the sources of dissolved ions. Physicochemical parameters of groundwater such as electrical conductivity, pH, total dissolved solid, and major cations and anions were determined. Chloride was found to be the dominant anion followed by HCO(-) 3 and SO4 (2-). Groundwater of the study area is characterized by the dominance of alkaline earths (Ca(2+) + Mg(2+)) over alkali metals (Na(+) + K(+)). The analytical results show that the groundwater is generally moderately hard and slightly alkaline in nature. The binary relationships of the major ions reveal that water quality of the Al-Ula region is mainly controlled by rock weathering, evaporation, and ion exchange reactions. Piper diagram was constructed to identify hydrochemical facies, and it was found that majority of the samples belong to Ca-Cl and mixed Ca-Mg-Cl facies. Chemical indices like chloro-alkali indices, sodium adsorption ratio, percentage of sodium, residual sodium carbonate, and permeability index were calculated. Also, the results show that the chemical composition of groundwater sources of Al-Ula is strongly influenced by lithology of country rocks rather than anthropogenic activities.

Luminescence recognition of different organophosphorus pesticides by the luminescent Eu(III)-pyridine-2,6-dicarboxylic acid probe.

Luminescence quenching of a novel long lived Eu(III)-pyridine-2,6-dicarboxylic acid probe of 1:2 stoichiometric ratio has been studied in 0.10 volume fraction ethanol-water mixture at pH 7.5 (HEPES buffer) in the presence of the organophosphorus pesticides chlorfenvinphos (P1), malathion (P2), azinphos (P3), and paraxon ethyl (P4). The luminescence intensity of Eu(III)-(PDCA)(2) probe decreases as the concentration of the pesticide increases. It was observed that the quenching due to P3 and P4 proceeds via both diffusional and static quenching processes. Direct methods for the determination of the pesticides under investigation have been developed using the luminescence quenching of Eu(III)-pyridine-2,6-dicarboxylic acid probe in solution. The linear range for determination of the selected pesticides is 1.0-35.0 µM. The detection limits were 0.24-0.55 µM for P3, P4, and P1 and 2.5 µM for P2, respectively. The binding constants (K), and thermodynamic parameters of the OPs with Eu(III)-(PDCA)(2) were evaluated. Positive and negative values of entropy (ΔS) and enthalpy (ΔH) changes for Eu(III)-(PDCA)(2)-P1 ternary complex were calculated. As the waters in this study do not contain the above mentioned OPs over the limit detectable by the method, a recovery study was carried out after the addition of the adequate amounts of the organophosphorus pesticides under investigation.

Bis(acridine-9-carboxylate)-nitro-europium(III) dihydrate complex a new apoptotic agent through Flk-1 down regulation, caspase-3 activation and oligonucleosomes DNA fragmentation.

New bis(acridine-9-carboxylate)-nitro-europium(III) dihydrate complex was synthesized and characterized. In vivo anti-angiogenic activities of bis(acridine-9-carboxylate)-nitro-europium(III) dihydrate complex against Ehrlich ascites carcinoma (EAC) cells are described. The newly synthesized complex resulted in inhibition of proliferation of EAC cells and ascites formation. The anti-tumor effect was found to be through anti-angiogenic activity as evident by the reduction of microvessel density in EAC solid tumors. The anti-angiogenic effect is mediated through down-regulation of VEGF receptor type-2 (Flk-1). The complex was also found to significantly increase the level of caspase-3 in laboratory animals compared to the acridine ligand and to the control group. This was also consistent with the DNA fragmentation detected by capillary electrophoresis that proved the apoptotic effect of the new complex. Our complex exhibited anti-angiogenic and apoptotic activity in vivo, a thing that makes it a potential effective chemotherapeutic agent. The interaction of calf thymus DNA (ct-DNA) with bis(acridine-9-carboxylate)-nitro-europium(III) dihydrate complex has been investigated using fluorescence technique. A competitive experiment of the europium(III)-acridine complex with ethidium bromide (EB) to bind DNA revealed that interaction between the europium(III)-acridine and DNA was via intercalation. The interaction of the synthesized complex with tyrosine kinases was also studied using molecular docking simulation to further substantiate its mode of action.

A novel anti-tumor agent, Ln(III) 2-thioacetate benzothiazole induces anti-angiogenic effect and cell death in cancer cell lines.

New complexes with a potent DNA-binding anti-tumor agent, europium(III)- and terbium(III)-2-thioacetate benzothiazole were synthesized and characterized. These complexes showed strong binding affinity to calf thymus DNA using fluorometric and electronic absorption spectroscopy. The synthesized complexes resulted in inhibition of proliferation of EAC cells and ascites formation. Their anti-tumor effect was found to be through anti-angiogenic activity as was evident by the reduction of microvessel density and down-regulation of VEGF receptor type-2 (Flk-1). It was found that EAC cells had distinct DNA fragmentation patterns analyzed by capillary electrophoresis in the treated animals. Moreover, the synthesized complexes exhibited significant cytotoxic activity against HepG2 and MCF7 cell lines. Furthermore, complexes showed a potent anti-bacterial activity against two pathogenic bacteria Escherichia coli and Salmonella.

Synthesis of novel Eu(III) luminescent probe based on 9- acridinecarboxylic acid skelton for sensing of ds-DNA.

Eu(III)-9-acridinecarboxylate (9-ACA) complex was synthesized and characterized by elemental analysis, conductivity measurement, IR spectroscopy, thermal analysis, mass spectroscopy, (1)H-NMR, fluorescence and ultraviolet spectra. The results indicated that the composition of this complex is [Eu(III)-(9-ACA)(2)(NCS)(C(2)H(5)OH)(2)] 2.5 H(2)O and the oxygen of the carbonyl group coordinated to Eu(III). The interaction between the complex with nucleotides guanosine 5'- monophosphate (5'-GMP), adenosine 5'-diphosphates (5'-ADP), inosine (5'-IMP) and CT-DNA was studied by fluorescence spectroscopy. The fluorescence intensity of Eu(III)-9-acridinecarboxylate complex was enhanced with the addition of CT-DNA. The effect of pH values on the fluorescence intensity of Eu(III) complex was investigated. Under experimental conditions, the linear range was 9-50 ng mL(-1) for calf thymus DNA (CT- DNA) and the corresponding detection limit was 5 ng mL(-1). The results showed that Eu(III)-(9-ACA)(2) complex binds to CT-DNA with stability constant of 2.41 × 10(4) M.