Use of Euphorbia balsamifera Extract in Precursor Fabrication of Silver Nanoparticles for Efficient Removal of Bromocresol Green and Bromophenol Blue Toxic Dyes.

Silver nanoparticles (Ag-NPs) are attracting great attention for their use in various applications, along with methods for their green and facile production. In this study, we present a new eco-friendly approach based on the use of Euphorbia balsamifera extract (EBE) in the green synthesis of silver nanoparticles (Ag-NPs), which are then applied as a reducing and stabilizing agent for the efficient removal of water-based reactive dyes such as bromocresol green (BCG) and bromophenol blue (BPB). The as-prepared Ag-NPs are quasi-spherical in shape, with an average diameter of 20-34 nm. Diverse characterization methods, including X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) analysis, were used to analyze these Ag-NPs. The results reveal that water-soluble biomolecules in the Euphorbia balsamifera extract play an important role in the formation of the Ag-NPs. The removal of toxic dyes was studied under varied operational parameters such as Ag-NP dosage, initial dye concentration, pH, stirring time, and temperature. Under the optimum investigated conditions, nearly 99.12% and 97.25% of the bromocresol green and bromophenol blue dyes, respectively, were removed. Both BCG and BPB adsorption were found to adhere to pseudo-second-order kinetics (r22 = 1 and 0.995) and fit the Langmuir isotherm models well (R12 = 0.998 and 0.994), with maximal monolayer adsorption capacities of 20.40 and 41.03 mg/g, respectively. Their adsorption processes were observed to be intrinsically endothermic. The results confirm the potential of the Euphorbia balsamifera extract as a low-cost, nontoxic, and eco-friendly natural resource for the synthesis of Ag-NPs that may be useful in the remediation of hazardous dye-contaminated water sources.

Biochemical Characterization and Antimicrobial Activity against Some Human or Phyto-Pathogens of New Diazonium Heterocyclic Metal Complexes.

String of vanadium (IV), zirconium (IV), palladium (II), platinum (IV) and uranium (VI) chelates of 2-cyano-2-[(2-nitrophenyl)hydrazono]thioacetamide (Cnphta) were prepared and characterized by physicochemical, spectroscopic and thermal analyses. The formulae of the isolated solid complexes were assigned as [VO(Cnphta)2 (H2 O)]SO4 ⋅ 5H2 O (1), [ZrO(Cnphta)2 (H2 O)]Cl2 ⋅ 4H2 O (2), [Pd(Cnphta)2 ]Cl2 (3), [Pt(Cnphta)2 Cl2 ]Cl2 (4) and [UO2 (Cnphta)2 ](NO3 )2 ⋅ 5H2 O (5). The infrared assignments clearly showed that Cnphta ligand coordinated as a bidentate feature through the hydrazono nitrogen and the thioacetamide nitrogen for V(IV), Zr(IV) and U(VI) but displayed different behavior for Pd(II) and Pt(IV). Results of the molar conductivities measurements showed that the metal complexes were electrolytes in contrast with Cnphta ligand. The interpretation, mathematical analysis and evaluation of kinetic parameters were also carried out. In addition, the studied ligand and its new chelates were tested for their antimicrobial activity against some human or phytopathogenic microorganisms. The new metal complexes explicated promising antibacterial activity against all tested bacteria especially Staphylococcus aureus and Bacillus subtilis. Regarding the antifungal activity, all metal complexes were able to inhibit the mycelium growth of both tested pathogenic fungi. In particular Zr(IV) and Pt(IV) complexes showed the highest significant fungicidal effect against A. fumigatus similar to positive control.

Spectrophotometric determination of Zr(IV), Hg(II) and U(VI) in solution with their analytical applications: Structural characterization and molecular docking of the solid complexes.

Spectrophotometry was used to determine trace amounts of Zirconium(IV), Mercury(II) and Uranium(VI) in environmental, biological, pharmaceutical and industrial samples. The determination depend on the complexation reactions between albendazole reagent and metal ions [Zr(IV), Hg(II) and U(VI)] at 555 nm, 485 nm and 510 nm, respectively. The experimental conditions were explored to reach the optimum conditions for albendazole-metal ions interaction, including detection of a suitable wavelength, medium (pH), reagent concentration, surfactants effect, reaction time and temperature. Under optimum conditions, the complexes displayed apparent molar absorptivities of 0.8350 × 104, 0.6210 × 104 and 0.7012 × 104 L mol-1 cm-1; Sandell's sensitivity of 0.01092, 0.03230 and 0.03394 µg cm-2 and with linearity ranges of 1.0-120.0, 3.0-200.0 and 1.0-150.0 µg mL-1 for the developed methods, respectively. Furthermore, Elemental analysis, thermal analysis (TGA, DTG), IR, 1HNMR, spectroscopies, electrical molar conductivity and magnetic moment measurements were used to determine the structures and characteristics of the complexes. A careful examination of the IR spectra revealed that the ligand interacted with all of the metal ions described as a bidentate via the oxygen of the carbonyl of the ester moiety and the nitrogen atom of the heterocyclic CN group. An octahedral geometry for Zr(IV), Hg(II) and U(VI) complexes has been postulated based on magnetic and electronic spectrum data. The band gap values indicated that these complexes were semi-conductors and belong to the same class of extremely effective solar materials. The albendazole ligand and its complexes have been biologically tested against a variety of bacterial and fungal strains, and molecular docking studies have been conducted to evaluate the optimal binding site and its inhibitory action.

Effective corrosion inhibition of mild steel in hydrochloric acid by newly synthesized Schiff base nano Co(ii) and Cr(iii) complexes: spectral, thermal, electrochemical and DFT (FMO, NBO) studies.

Two new cobalt(ii) and chromium(iii) complexes were synthesized and characterized by FT-IR, 1HNMR, UV, elemental analysis, TGA, conductivity, XRD, SEM, and magnetic susceptibility measurements. Structural analysis revealed a bi-dentate chelation and octahedral geometry for the synthesized complexes. The optical band gap of the Co(ii)-L and Cr(iii)-L complexes was found to be 3.00 and 3.25 eV, respectively revealing semiconducting properties. The X-ray diffraction patterns showed nano-crystalline particles for the obtained complexes. In addition, the synthesized metal complexes were examined as corrosion inhibitors for mild steel in HCl solution. The electrochemical investigations showed a maximum inhibition efficiency of 96.60% for Co(ii)-L and 95.45% for Cr(iii)-L where both complexes acted as mixed-type inhibitors. Frontier Molecular orbital (FMO) and Natural bond orbital (NBO) computations showed good tendency of the ligand to donate electrons to the metal through nitrogen atoms while the resultant complexes tended to donate electrons to mild steel more effectively through oxygen atoms and phenyl groups. A comparison between experimental and theoretical findings was considered through the discussion.

Spectral, thermal, antimicrobial studies for silver(I) complexes of pyrazolone derivatives.

BACKGROUND: Synthesize new complexes of Ag(I) to enhance efficacy or stability and also, pharmacological activities on the operation of pyrazolone's biological properties. RESULTS: Efficient and high yielding pathways starting from the versatile and readily available 3-methyl-1-phenyl-5-pyrazolone by Knoevenagel condensation of a sequence of 4-arylidene-3-methyl-1-phenyl-5-pyrazolone derivatives (2a-c) have been formed by the reaction of various substituted aromatic aldehydes Used as ligands to synthesize Ag(I) chelates. Synthesized compounds and their complexes have been characterized by elemental analysis, magnetic and spectroscopic methods (IR, 13C, 1HNMR, mass) and thermal analysis. The spectrophotometric determinations suggest distorted octaedral geometry for all complexes. Both ligands and their metal complexes have also been tested for their antibacterial and antifungal efficacy. CONCLUSIONS: Newly synthesized compounds have shown potent antimicrobial activity. The results showed that the complex 's high activity was higher than its free ligands, and that Ag(I)-L3 had the highest activity.

Synthesis, spectral, DFT modeling, cytotoxicity and microbial studies of novel Zr(IV), Ce(IV) and U(VI) piroxicam complexes.

The Zr(IV), Ce(IV) and U(VI) piroxicam anti-inflammatory drug complexes were prepared and characterized using elemental analyses, conductance, IR, UV-Vis, magnetic moment, IHNMR and thermal analysis. The ratio of metal: Pir is found to be 1:2 in all complexes estimated by using molar ratio method. The conductance data reveal that Zr(IV) and U(VI) chelates are non-electrolytes except Ce(IV) complex is electrolyte. Infrared spectroscopic confirm that the Pir behaves as a bidentate ligand co-ordinated to the metal ions via the oxygen and nitrogen atoms of ν(CO)carbonyl and ν(CN)pyridyl, respectively. The kinetic parameters of thermogravimetric and its differential, such as activation energy, entropy of activation, enthalpy of activation, and Gibbs free energy evaluated using Coats-Redfern and Horowitz-Metzger equations for Pir and complexes. The geometry of the piroxicam drug in the Free State differs significantly from that in the metal complex. In the time of metal ion-drug bond formation the drug switches-on from the closed structure (equilibrium geometry) to the open one. The antimicrobial tests were assessed towards some types of bacteria and fungi. The in vitro cell cytotoxicity of the complexes in comparison with Pir against colon carcinoma (HCT-116) cell line was measured.

Synthesis, characterization and antimicrobial investigation of some moxifloxacin metal complexes.

The new complexes of moxifloxacin (MOX), with Ti(IV), Y(III), Pd(II) and Ce(IV) have been synthesized. These complexes were then characterized by melting point, magnetic studies and spectroscopic techniques involving infrared spectra (IR), UV-Vis, (1)H NMR. C, H, N and halogen elemental analysis and thermal behavior of complexes also investigated. The results suggested that the molar ratio for all complexes is M: MOX=1:2 where moxifloxacin acts as a bidentate via one of the oxygen atoms of the carboxylate group and through the ring carbonyl group and the complexes have the following formula [Ti(MOX)(2)](SO(4))(2)·7H(2)O, [Y(MOX)(2)Cl(2)]Cl·12H(2)O, [Pd(MOX)(2)(H(2)O)(2)]Cl(2)·6H(2)O and [Ce(MOX)(2)](SO(4))(2)·2H(2)O. The activation energies, E*, enthalpies, ΔH*, entropies, ΔS* and Gibbs free energies, ΔG*, of the thermal decomposition reactions have been derived from thermogravimetric (TGA) and differential thermogravimetric (DrTG) curves, using Coats-Redfern (CR) and Horowitz-Metzger (HM) methods. The antimicrobial activity of these complexes has been evaluated against three Gram-positive and three Gram-negative bacteria and compared with the reference drug moxifloxacin. The antibacterial activity of Ti(IV) complex is significant for E. coli K32 and highly significant for S. aureus K1, B. subtilis K22, Br. otitidis K76, P. aeruginosa SW1 and K. oxytoca K42 compared with free moxifloxacin.

Spectroscopic, structure and antimicrobial activity of new Y(III) and Zr(IV) ciprofloxacin.

The preparation and characterization of the new solid complexes [Y(CIP)2(H2O)2]Cl(3)·10H2O and [ZrO(CIP)2Cl]Cl·15H2O formed in the reaction of ciprofloxacin (CIP) with YCl3 and ZrOCl(2)·8H2O in ethanol and methanol, respectively, at room temperature were reported. The isolated complexes have been characterized with elemental analysis, IR spectroscopy, conductance measurements, UV-vis and 1H NMR spectroscopic methods and thermal analyses. The results support the formation of the complexes and indicate that ciprofloxacin reacts as a bidentate ligand bound to the metal ion through the pyridone oxygen and one carboxylato oxygen. The activation energies, E*; entropies, ΔS*; enthalpies, ΔH*; Gibbs free energies, ΔG*, of the thermal decomposition reactions have been derived from thermogravimetric (TGA) and differential thermogravimetric (DTG) curves, using Coats-Redfern and Horowitz-Metzeger methods. The proposed structure of the two complexes was detected by using the density functional theory (DFT) at the B3LYP/CEP-31G level of theory. The ligand as well as their metal complexes was also evaluated for their antibacterial activity against several bacterial species, such as Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) and antifungal screening was studied against two species (Penicillium (P. rotatum) and Trichoderma (T. sp.)). This study showed that the metal complexes are more antibacterial as compared to free ligand and no antifungal activity observed for ligand and their complexes.