Search Results (118)

Metal ions, including Mg(II), Ca(II), Sr(II), Co(II), Ni(II), Cu(II), Nd(III), Eu(III), and Tb(III), were investigated in binary systems alongside ampicillin at molar ratios of 1:1 and 1:2. These investigations were carried out in aqueous solutions, and the formation of complexes was verified through meticulous computational analysis. Detailed stability constants for the formed complexes and equilibrium constants for the involved reactions were meticulously determined. Furthermore, a comprehensive examination of the impact of ligand concentration on the configuration of the central metal atom’s coordination sphere was conducted. This investigation was complemented by spectroscopic measurements, which effectively confirmed the observed changes in the coordination sphere of the metal ions. Full article

Incorporation of lanthanide (Ln) and actinide (An) ions into the human body poses significant chemotoxic and radiotoxic risks, necessitating effective decorporation strategies. This study investigates the displacement of biologically relevant ligands from trivalent ions of europium, Eu(III), and curium, Cm(III), in artificial biofluids by various complexing agents, i.e., ethylenediaminetetraacetic acid (EDTA), ethylene glycol-bis(β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid (EGTA), diethylenetriaminepentaacetic acid (DTPA), and spermine-based hydroxypyridonate chelator 3,4,3-LI(1,2-HOPO) (HOPO). Utilizing a modified unified bioaccessibility method (UBM) to simulate gastrointestinal conditions, we conducted concentration-dependent displacement experiments at both room and body temperatures. Time-resolved laser-induced fluorescence spectroscopy (TRLFS) supported by ²H nuclear magnetic resonance (NMR) spectroscopy and thermodynamic modelling revealed the complexation efficacy of the agents under physiological conditions. Results demonstrate that high affinity, governed by complex stability constants and ligand pK_a values, is critical to overcome cation and anion competition and leads to effective decorporation. Additionally, there is evidence that cyclic ligands are inferior to linear ligands for this application. HOPO and DTPA exhibited superior displacement efficacy, particularly in the complete gastrointestinal tract simulation. This study highlights the utility of in vitro workflows for evaluating decorporation agents and emphasizes the need for ligands with optimal binding characteristics for enhanced chelation therapies. Full article

The coordination chemistry, structural characterization, and biomolecular interactions of europium(III) and iron(III) complexes with the pyridoxal-semicarbazone (PLSC) ligand were thoroughly examined using experimental and computational approaches. Single-crystal X-ray diffraction revealed that the europium complex exhibits a nine-coordinate geometry with one protonated and one deprotonated PLSC ligand and nitrato and aqua ligands. In contrast, the iron complex adopts a six-coordinate structure featuring a monoprotonated PLSC, two chlorido, and an aqua ligand. Hirshfeld surface analysis confirmed the significance of intermolecular contacts in stabilizing the crystal lattice. Theoretical geometry optimizations using DFT methods demonstrated excellent agreement with experimental bond lengths and angles, thereby validating the reliability of the chosen computational levels for subsequent quantum chemical analyses. Quantum Theory of Atoms in Molecules (QTAIM) analysis was employed to investigate the nature of metal–ligand interactions, with variations based on the identity of the donor atom and the ligand’s protonation state. The biological potential of the complexes was evaluated through spectrofluorimetric titration and molecular docking. Eu-PLSC displayed stronger binding to human serum albumin (HSA), while Fe-PLSC showed higher affinity for calf thymus DNA (CT-DNA), driven by intercalation. Thermodynamic data confirmed spontaneous and enthalpy-driven interactions. These findings support using PLSC-based metal complexes as promising candidates for future biomedical applications, particularly in drug delivery and DNA targeting. Full article

Progressing soil degradation worldwide is a complex socio-environmental threat. Implementing environmental policies and actions such as the Sustainable Development Goals, the European Green Deal, and the Renewable Energy Directive III regarding environmental protection aims to protect, conserve, and enhance the EU’s natural capital, focusing on soil protection. As assumed in the Green Deal, the European economy has to be turned into a resource-efficient and green economy with zero net emission of greenhouse gases. Since soil quality strongly influences all ecosystem elements, soil remediation is increasingly promoted as a sustainable option to enhance soil quality and, at the same time, help achieve overarching goals set out in European climate law. Biomass in phytoremediation is particularly important in regenerative agriculture, as it emphasizes improving soil quality, increasing biodiversity, and sequestering carbon. Selected plants and microbes can clean degraded agricultural areas, removing heavy metals and pesticides, thus lowering soil toxicity and improving food and feed security. Moreover, the post-phytoremediation biomass can be processed into biofuels or bioproducts, supporting the circular economy. This article summarizes the role of plants and microbial biomass in the struggle to achieve EU environmental goals, enabling the regeneration of degraded ecosystems while supporting sustainable development in agriculture. Full article

In this paper, we investigate the magnetic exchange interaction and magnetization dynamics of two new members of the [LnRad(NO₃)₃] family, where Rad is a tripodal nitroxide, and Ln is Er(III) or Yb(III), having the prolate type electron density. Single OK crystal and powder X-ray diffraction studies showed that these complexes are isostructural with their previously investigated Y, Gd, Dy, Tm, Tb, Eu, and Lu congeners. A magnetometric investigation, supported by ab initio calculations, showed the presence of antiferromagnetic coupling between the lanthanide ion and the radical in both compounds with estimated J values of ≈7 and ≈20 cm⁻¹ for Er and Yb, respectively (+J S_eff∙ S formalism). Full article

The synergistic solvent extraction of La(III), Eu(III) and Lu(III) with a chelating extractant, 4-benzoyl-3-methyl-1-phenyl-2-pyrazolin-5-one (HL), and neutral bidentate heterocyclic amines, such as 1,10-phenanthroline (S1 (phen)) or 2,2′-bipyridine (S2 (bipy)) in an ionic liquid of the imidazolium family [C₁C₄im⁺][Tf₂N⁻] was investigated. Synergistic effects have been observed to result from the formation of a ternary complex in the organic phase, particularly in cases where the ligand S is a neutral synergistic agent. Examples include La(L)₂(S2)₂, Eu(L)₃(S2) and Lu(L)_x(S2)₂, as well as La(L)₃(S1)₂, Eu(L)₂(S1) and Lu(L)₃(S1)_x). The parameters of the solvent extraction process were determined and the influence of the synergistic agent on the extraction process was discussed. Additionally, the synergistic increase and separation factors were determined. The equilibrated organic phases were analyzed using ¹H NMR spectroscopy to elucidate the synergism in an extraction mechanism. The role of the ionic diluent in complexation processes and selectivity was investigated with the employment of the two synergistic agents for various metal s-, p-, d- and f-cations in the periodic table, with almost 22 metal ions. Full article

Lanthanides have seen rapid growth in the pharmaceutical and biomedical field, thus necessitating the development of hybrid metal–organic materials capable of exerting defined biological activities. Ternary hybrid lanthanide compounds were synthesized through reaction systems of Ln(III) (Ln = La, Nd, Eu) involving the antioxidant flavonoid chrysin (Chr) and 1,10-phenanhtroline (phen) under solvothermal conditions, thus leading to pure crystalline materials. The so-derived compounds were characterized physicochemically in the solid state through analytical (elemental analysis), spectroscopic (FT-IR, UV-visible, luminescence, ESI-MS, circular dichroism, ¹⁵¹Eu Mössbauer), magnetic susceptibility, and X-ray crystallographic techniques. The analytical and spectroscopic data corroborate the 3D structure of the mononuclear complex assemblies and are in line with theoretical calculations (Bond Valence Sum and Hirshfeld analysis), with their luminescence suggesting quenching on the flavonoid-phen electronic signature. Magnetic susceptibility data suggest potential correlations, which could be envisioned, supporting future functional sensors. At the biological level, the title compounds were investigated for their (a) ability to interact with bovine serum albumin and (b) antibacterial efficacy against Gram(−) (E. coli) and Gram(+) (S. aureus) bacteria, collectively revealing distinctly configured biological profiles and suggesting analogous applications in cellular (patho)physiologies. Full article

The European Union continues to lead global efforts toward climate neutrality by developing a cohesive regulatory and market framework for alternative fuels, including renewable hydrogen. This review article critically examines the recent evolution of the EU’s policy landscape specifically for hydrogen as a renewable fuel of non-biological origin (RFNBO), highlighting its growing importance in hard-to-abate sectors such as industry and transportation. We assess the interplay of market-based mechanisms (e.g., EU ETS II), direct mandates (e.g., FuelEU Maritime, RED III), and support auction-based measures (e.g., the European Hydrogen Bank) that collectively shape both the demand and the supply of hydrogen as RFNBO fuel. The article also addresses emerging cost, capacity, and technical barriers—ranging from constrained electrolyzer deployment to complex certification requirements—that hinder large-scale adoption and market rollout. The article aims to discuss advancing and changing regulatory and market environment for the development of infrastructure and market for hydrogen as RFNBO fuel in the EU in 2019–2024. Synthesizing current research and policy developments, we propose targeted recommendations, including enhanced cross-border coordination and capacity-based incentives, to accelerate investment and infrastructure development. This review informs policymakers, industry stakeholders, and researchers on critical success factors for integrating hydrogen as a cornerstone of the EU’s climate neutrality efforts. Full article

This study conducted adsorption experiments using Europium (Eu(III)) on geological materials collected from Taiwan. Batch tests on argillite, basalt, granite, and biotite showed that argillite and basalt exhibited strong adsorption reactions with Eu. X-ray diffraction (XRD) analysis also clearly indicated differences before and after adsorption. By combining X-ray absorption near-edge structure (XANES), extended X-ray absorption fine structure (EXAFS), and wavelet transform (WT) analyses, we observed that the Fe₂O₃ content significantly affects the Eu-Fe distance in the inner-sphere layer during the Eu adsorption process. The wavelet transform analysis for two-dimensional information helps differentiate two distances of Eu-O, which are difficult to analyze, with hydrated outer-sphere Eu-O distances ranging from 2.42 to 2.52 Å and inner-sphere Eu-O distances from 2.27 to 2.32 Å. The EXAFS results for Fe₂O₃ and SiO₂ in argillite and basalt reveal different adsorption mechanisms. Fe₂O₃ exhibits inner-sphere surface complexation in the order of basalt, argillite, and granite, while SiO₂ forms outer-sphere ion exchange with basalt and argillite. Wavelet transform analysis also highlights the differences among these materials. Full article

Seven new lanthanide coordination polymers, namely [Ln(cpt)₃H₂O)]n(Ln = La (1), Pr (2), Sm (3), Eu (4), Gd (5), Dy (6), and Er (7)), which were synthesized under hydrothermal conditions using 4′-(4-(4-carboxyphenyloxy)phenyl)-4,2′:6′,4′-tripyridine (Hcpt) as the ligand. The crystal structures of these seven complexes were determined using single-crystal X-ray diffraction, and they were found to be isostructural, crystallizing in the triclinic P$\stackrel{-}{1}$ space group. The Ln(III) ions were nine-coordinated with tricapped trigonal prism coordination geometry. The Ln(III) cations were coordinated by carboxylic and pyridine groups from (cpt)⁻ ligands, forming one-dimensional ring-chain structures. Furthermore, the luminescent properties of complexes 1–7 were investigated using fluorescent spectra in the solid state. The fluorescence sensing experiments demonstrated that complex 4 exhibits high selectivity and sensitivity for detecting Co²⁺, Cu²⁺ ions, and nitrobenzene. Moreover, complex 3 shows good capability for detecting Cu²⁺ ions and nitrobenzene. Additionally, the sensing mechanism was also thoroughly examined through theoretical calculations. Full article

National pricing and reimbursement agencies face growing challenges with complex health technologies, prompting European policy advancements. Beneluxa is a cross-country collaboration involving Belgium, the Netherlands, Luxemburg, Austria, and Ireland that aims to address sustainable access to medicines. In view of the soon-to-be-implemented EU HTA Regulation, insights and experiences from stakeholders with Beneluxa cross-country collaboration could provide possible transferable learnings. Therefore, this research aims to (i) identify the opportunities and challenges faced by Beneluxa, (ii) gather insights from stakeholders, namely (possible) applicants and policymakers, within and beyond Beneluxa on the initiative and broader cross-country collaboration principles, and (iii) transfer these insights into learnings and recommendations in anticipation of the full implementation of the new HTA Regulation. Fifteen semi-structured interviews were conducted with industry and European HTA/policy stakeholders. The principal challenges discussed by stakeholders encompass hesitancy from the industry toward Beneluxa assessments, which were attributed to procedural and timeline uncertainties, legislative framework ambiguity, and challenges in terms of industry’s internal organization. Another challenge highlighted is the resource-intensive nature of the procedure due to diverse approaches among member states. In addition, industry stakeholders mentioned limited communication and procedural complexity. Despite challenges, both stakeholder groups recognized important opportunities for cross-country collaboration. Transferable insights for future cross-country collaboration include transparent communication, clear legislative embedding, internal industry restructuring to facilitate joint HTAs, and member state support for conducting collaborative assessments. The study underscores diverging views among stakeholders on cross-country collaboration’s potential to support HTA and the market access of complex health technologies. While acknowledging benefits, there still are challenges, including industry hesitancy, emphasizing the need for transparent communication and clear guidance in the evolving EU HTA landscape. Full article

Six cattle heads which tested positive against bovine tuberculosis (bTB) in Morocco were investigated to confirm the disease and to determine the source(s) of infection. Polymerase Chain Reaction (PCR) was directly performed on tissue samples collected from slaughtered animals. All investigated animals tested positive to PCR for the Mycobacterium bovis sub-type. Bacteriological isolation was conducted according to the technique recommended by WOAH for the cultivation of the Mycobacterium tuberculosis Complex (MBTC). Whole genome sequencing (WGS) was carried out on six mycobacterial isolates and the phylogenic tree was constructed. The six Moroccan isolates fit with clades II, III, IV, V and VII and were confirmed to belong to the clonal complexes Eu2, Unknown 2 and 7 as well as to sublineages La1.7.1, La1.2 and La1.8.2. The significant Single Nucleotide Polymorphism (SNPs) ranged from 84 to 117 between the isolates and the reference M. bovis strain and from 17 to 212 between the six isolates. Considering the high resolution of WGS, these results suggests that the source of infection of the bTB could be linked to imported animals as five of the investigated reactor animals were imported a few months prior. WGS can be a useful component to the Moroccan strategy to control bTB. Full article

Coordination complexes of lanthanide metals with tris-1-naphthylphosphine oxide (Nap₃PO, L) have not been previously reported in the literature. We describe here the formation of lanthanide(III) nitrate complexes Ln(NO₃)₃L₄ (Ln = Eu to Lu) and the structures of [Ln(NO₃)₃L₂]·2L (Ln = Eu, Dy, Ho, Er) and L. The core structure of the complexes is an eight-coordinate [Ln(NO₃)₃L₂] with the third and fourth ligands H-bonded via their oxygen atoms to one of the naphthyl rings. The structures are compared with those of the analogous complexes of triphenylphosphine oxide and show that the Ln-O(P) bond in the Nap₃PO complexes is slightly longer than expected on the basis of differences in coordination numbers. The reaction solutions, investigated by ³¹P and ¹³C NMR spectroscopy in CD₃CN, show that coordination of L occurs across the lanthanide series, even though complexes can only be isolated from Eu onwards. Analysis of the ³¹P NMR paramagnetic shifts shows that there is a break in the solution structures with a difference between the lighter lanthanides (La–Eu) and heavier metals (Tb–Lu) which implies a minor difference in structures. The isolated complexes are very poorly soluble, but in CDCl₃, NMR measurements show dissociation into [Ln(NO₃)₃L₂] and 2L occurs. Full article

Leishmaniases are neglected diseases with limited therapeutic options. Diffuse cutaneous leishmaniasis can occur in Brazil due to Leishmania amazonensis. This study details the antileishmanial activity and cytotoxicity of complexes of sodium usnate (SAU) with lanthanide ions ([LnL₃ (H₂O)_x] (Ln = La(III), Nd(III), Gd(III), Tb(III), Eu(III) and Sm(III); L = SAU). All lanthanide complexes were highly active and more potent than SAU against L. amazonensis promastigotes and intracellular amastigotes (Pro: IC₅₀ < 1.50 μM; Ama: IC₅₀ < 7.52 μM). EuL₃·3H₂O and NdL₃·3H₂O were the most selective and effective on intracellular amastigotes, with a selectivity index of approximately 7.0. In silico predictions showed no evidence of mutagenicity, tumorigenicity or irritation for all complexes. Treatment with EuL₃·3H₂O triggered NO release even at the lowest concentration, indicating NO production as a mechanism of action against the parasite. Incubating promastigotes with the lanthanide complexes, particularly with SmL₃·4H₂O and GdL₃·3H₂O, led to a change in the mitochondrial membrane potential, indicating the ability of these complexes to target this essential organelle. The same complexes caused cell death through cell membrane disruption, but their relationship with early or late apoptotic processes remains unclear. Thus, the inclusion of lanthanide ions in SAU improves selectivity with a promising mechanism of action targeting the mitochondria. Full article

In this publication, the potential non-gadolinium magnetic resonant imaging agent—nanoparticulate K₂Mn[Fe(CN)₆]—its comparison sample KFe[Co(CN)₆], as well as their reference samples were measured and analyzed using Mn, Co and Fe L-edge X-ray absorption spectroscopy (L XAS). From the information obtained, we conclude that K₂Mn[Fe (CN)₆] has a high spin (hs)-Mn(II) and a low spin (ls)-Fe(II), while KFe[Co(CN)₆] has an hs-Fe(II) and an ls-Co(III). In these Prussian blue (PB) analog structures, the L XAS analysis also led to the conclusion that the hs-Mn(II) in K₂Mn[Fe(CN)₆] or the hs-Fe(II) in KFe[Co(CN)₆] bonds to the N in the [M(CN)₆]^4−/3− ions (where M = Fe(II) or Co(III)), while the ls-Fe(II) in K₂Mn[Fe(CN)₆] or the ls-Co(III) in KFe[Co(CN)₆] bonds to the C in the [M(CN)₆]^4−/3− ion, suggesting the complexed metalloligand [Mn(II) or Fe(II)] occupies the N-bound site in PB. Then, nuclear resonant vibrational spectroscopy (NRVS) was used to confirm the results from the L XAS measurements: the Mn(II), Eu(III), Gd(III), Fe(II) cations complexed by [M(CN)₆]ⁿ⁻-metalloligand all take the N-bound site in PB-like structures. Our NRVS studies also prove that iron in the K₂Mn[Fe(CN)₆] compound has a 2+ oxidation state and is surrounded by the C donor atoms in the [M(CN)₆]ⁿ⁻ ions. Full article