Application of zirconium aspartic acid metal-organic framework (MIP-202(Zr)) for high efficient ruthenium adsorption from aqueous solutions.

The zirconium metal - organic framework MIP-202(Zr), based on L-aspartic acid, was prepared by hydrothermal method and used for study of ruthenium adsorption from aqueous solutions. The obtained material was characterized by X-ray diffraction (XRD), infra red spectroscopy (IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The batch adsorption experiment was performed for determination of adsorption equilibrium, kinetics and thermodynamics parameters to Ru(III) from aqueous solution on MIP-202(Zr). The data of ruthenium sorption onto MIP-202(Zr) were fitted and analyzed by the Langmuir, Freundlich and Temkin equilibrium isotherm models, while the Langumir adsorption isotherm models fit the best. Kinetic data were analyzed by four kinetic models, and ruthenium sorption on MIP202(Zr) can be describes the best by intra particle diffusion (Weber Morris). Analysis of thermodynamic properties of ruthenium ions sorption onto MIP-202(Zr) shows that the sorption process has a spontaneous and endothermic nature and is energetically beneficial.

Flavonol-ruthenium complexes as antioxidant and anticancer agents.

Flavonol-metal complexes can enhance the biological activity of flavonols. Inspired by the potential of ruthenium-based drugs in pharmaceutical applications, seven flavonol-Ru (II) complexes were synthesized to evaluate their biological activities. Among these compounds, compounds 8, 11, and 12 showed potent antioxidant activities. Compound 12 exhibited superior anti-inflammatory activity to natural quercetin, which served as a positive control. This study is the first to report the free radical scavenging abilities and antioxidant activity of flavonol-Ru (II) complexes. Furthermore, compound 12 demonstrated comparable efficacy to 5-FU against human non-small-cell lung cancer cells (A549). These results strongly support the potential of flavonol-Ru (II) agents.

A ruthenium single atom nanozyme-based antibiotic for the treatment of otitis media caused by Staphylococcus aureus.

Staphylococcus aureus (S. aureus) infection is a primary cause of otitis media (OM), the most common disease for which children are prescribed antibiotics. However, the abuse of antibiotics has led to a global increase in antimicrobial resistance (AMR). Nanozymes, as promising alternatives to traditional antibiotics, are being extensively utilized to combat AMR. Here, we synthesize a series of single-atom nanozymes (metal-C3N4 SANzymes) by loading four metals (Ag, Fe, Cu, Ru) with antibacterial properties onto a crystalline g-C3N4. These metal-C3N4 display a rob-like morphology and well-dispersed metal atoms. Among them, Ru-C3N4 demonstrates the optimal peroxidase-like activity (285.3 U mg-1), comparable to that of horseradish peroxidase (267.7 U mg-1). In vitro antibacterial assays reveal that Ru-C3N4 significantly inhibits S. aureus growth compared with other metal-C3N4 even at a low concentration (0.06 mg mL-1). Notably, Ru-C3N4 acts as a narrow-spectrum nanoantibiotic with relative specificity against Gram-positive bacteria. Biofilms formed by S. aureus are easily degraded by Ru-C3N4 due to its high peroxidase-like activity. In vivo, Ru-C3N4 effectively eliminates S. aureus and relieves ear inflammation in OM mouse models. However, untreated OM mice eventually develop hearing impairment. Due to its low metal load, Ru-C3N4 does not exhibit significant toxicity to blood, liver, or kidney. In conclusion, this study presents a novel SANzyme-based antibiotic that can effectively eliminate S. aureus and treat S. aureus-induced OM.

Adjuvant Brachytherapy with Ruthenium-106 to Reduce the Risk of Recurrence of Conjunctival Melanoma after Excision.

Introduction: Local recurrence of conjunctival melanoma (CM) is common after excision. Local radiotherapy is an effective adjuvant treatment option, and brachytherapy with ruthenium-106 (106Ru) is one such option. Thus, herein, we aimed to describe our experience with and the clinical results of post-excision adjuvant 106Ru plaque brachytherapy in patients with CM. Methods: Nineteen patients (8 men and 11 women) received adjuvant brachytherapy with a 106Ru plaque after tumor excision. The mean adjuvant dose administered was 109 Gy (range, 80-134 Gy), and a depth of only 2.2 mm was targeted because the tumor had been excised. A full ophthalmological examination including visual acuity testing, slit-lamp examination, and indirect ophthalmoscopy was performed before therapy and at every postoperative follow-up. The mean follow-up period was 62 months (range, 2-144 months). Results: Three patients developed a recurrence in a nontreated area, at either the conjunctiva bulbi or the conjunctiva tarsi. None of the patients developed a recurrence in the treated area. The local control rate was 84% (16/19). Conclusion: 106Ru plaque brachytherapy is an effective adjuvant treatment to minimize the risk of local recurrence after excision of a CM. Patients have to be followed up regularly and carefully for the early detection of recurrence.

Ruthenium-106 Plaque Brachytherapy for Circumscribed Choroidal Hemangioma: A Case Series and Review of Literature.

Introduction: We aim to report the anatomical and functional outcomes of ruthenium-106 brachytherapy in the management of circumscribed choroidal hemangiomas (CCH). Methods: This is a single-center, retrospective case series including patients with unilateral symptomatic CCH treated with ruthenium-106 brachytherapy at the Cairo University Ocular Oncology Service. Patient records were analyzed for patients' demographics, best corrected visual acuity (BCVA), tumor dimensions (thickness and largest base diameter), foveal subretinal fluid, radiation-related complications, and recurrence. Results: Seven patients were included in the study (including 6 males) with a mean age of 39.3 ± 15.4 years; ruthenium-106 plaque was used to deliver 50 Gray to the tumor apex. After a mean follow-up duration of 12.5 months, all patients had significant improvement in BCVA after treatment, mean tumor height decreased significantly from 4.76 ± 1.76 mm to 1.70 ± 1.2 mm (p value 0.01). The largest tumor base diameter also decreased significantly from 9.13 ± 2.68 mm to 4.65 ± 3.75 mm (p value 0.05). Subretinal fluid and exudative retinal detachment resolved in all patients, and no significant radiation-related complications were observed in any patient. None of the patients needed any further treatment or experienced recurrence within the follow-up period. Conclusion: Ruthenium-106 brachytherapy is an effective tool in the management of symptomatic CCH with a good visual prognosis and safety profile.

Multicolor Electrochemiluminescence of Binary Microcrystals of Iridium and Ruthenium Complexes.

We here report the multicolor electrochemiluminescence (ECL) of binary microcrystals prepared from a blue-emissive iridium complex 1 and an orange-emissive ruthenium complex 2. These materials display a plate-like morphology with high crystallinity, as demonstrated by microscopic and powder X-ray diffraction analyses. Under light excitation, these microcrystals exhibit gradient emission color changes as a result of the efficient energy transfer between two complexes. When modified on glass carbon electrodes, these microcrystals exhibit tunable ECLs with varied emission colors including sky-blue, white, orange, and red, depending the doping ratio of complex 2 and the applied potential. Furthermore, organic amines with different molecular sizes are used as the co-reactant to examine their influences on the ECL efficiency of the porous microcrystals of 1. The analysis on the luminance and RGB values of ECL suggests the existence of energy transfer in the generation of multicolor ECLs in these binary crystals.

Room-Temperature Possible Current-Induced Transition in Ca2RuO4 Thin Films Grown Through Intercalation-Like Cation Diffusion in the A2BO4 Ruddlesden-Popper Structure.

Cation deficiency tuning is a central issue in thin-film epitaxy of functional metal oxides, as it is typically more difficult than anion deficiency tuning, as anions can be readily supplied from gas sources. Here, highly effective internal deficiency compensation of Ru cations is demonstrated for Ca2RuO4 epitaxial films based on diffusive transfer of metal cations in the A2BO4 Ruddlesden-Popper lattice from solid-phase cation sources. Through detailed structural characterization of Ca2RuO4/LaAlO3 (001) thin films grown with external cation sources by solid-phase epitaxy, the occurrence of intercalation-like, interstitial diffusion of La cations (from the substrates) in the A2BO4 structure is revealed, and that of Ru cations is also suggested. Relying on the interstitial-type diffusion, an optimized Ru deficiency compensation method, which does not induce the formation of Can +1RunO3 n +1 Ruddlesden-Popper impurity phases with higher n, is proposed for Ca2RuO4 epitaxial films. In the Ca2RuO4/LaAlO3 (001) thin films grown with Ru deficiency compensation, record-high resistivity values (102-10-1 Ω cm) and a large (more than 200 K) increase in the temperature range of the nonlinear transport properties are demonstrated by transport measurements, demonstrating the possible advantages of this method in the control of the current-induced quantum phase transition of Ca2RuO4.

Electronic structure of light-induced nitrosyl linkage isomers revealed by X-ray absorption spectroscopy at Ru L3,2-edges.

X-ray absorption spectroscopy (XAS) is a powerful tool for examining changes of the electronic and molecular structure following light-induced excitation of a molecule. Specifically, this method can be applied to investigate the ground (GS, RuNO) and metastable states (MS1, RuON and MS2, Ruη2(NO)) of the nitrosyl ligand (NO), which differ in their coordination mode to the metal. In this work, we report for the first time experimental and theoretical (DFT) Ru L3,2-edge XA spectra for the octahedral complex trans-[RuNOPy4F](ClO4)2 (1, Py = pyridine) in both ground and metastable states. The transition from GS to MS1 using 420 nm light excitation leads to a significant downshift of the 2p â†’ LUMO(+1) peaks by about 0.5-0.8 eV, attributed to the destabilisation of 2p orbitals and stabilization of LUMO(+1). Subsequent irradiation of MS1 at 920 nm produces isomer MS2, for which even greater stabilization of LUMO occurs, though without a significant change in 2p energy. The change in 2p energy is attributed to a variation in the charge on the Ru atom after NO isomerization, while LUMO(+1) stabilization is related to changes in the Ru(NO) bond length and the composition of this orbital.

Ultrathin ternary PtNiRu nanowires for enhanced oxygen reduction and methanol oxidation catalysis via d-band center regulation.

Direct methanol fuel cells rely on the efficiency of their anode/cathode electrocatalysts to facilitate the methanol oxidation reaction and oxygen reduction reaction, respectively. Platinum-based nanocatalysts are at the forefront due to their superior catalytic properties. However, the high-cost, scarcity, and low CO tolerance of platinum pose challenges for the scalable application of DMFCs. Herein, we report novel ultrathin ternary PtNiRu alloy nanowires to improve Pt utilization and CO tolerance. These novel electrocatalysts incorporate the oxophilic metal Ru into ultrathin PtNi nanowires, aiming to enhance the intrinsic activity of platinum while leveraging the long-term durability and high utilization efficiency provided by the bimetallic synergistic effect. The PtNiRu NWs significantly enhance both mass activity and specific activity for ORR, performing about 6.9 times and 3.9 times better than commercial Pt/C, respectively. After a rigorous durability test of 10,000 cycles, the PtNiRu NWs only exhibited a 25.2 % loss in mass activity. Additionally, for MOR, the MA and SA of PtNiRu NWs exceed that of Pt/C catalyst by 4.30 and 2.72 times, respectively, and exhibit exceptional resistance to CO poisoning. Theoretical insights from density functional theory calculations suggest that the introduction of Ru modulates the d-band center of the surface Pt atoms, which contributes to decreased binding strength of oxygenated species and an elevated dissolution potential, substantiating the enhanced performance metrics, and the durability enhancement stems from the stronger PtM bonds than those in PtNiRu NWs resulted from PtRu covalent interactions. These findings not only provide a new perspective on platinum-based nanocatalysts but also significantly advance the quest for more efficient and durable electrocatalysts for DMFCs, representing a substantial stride in fuel cell technology.

NIR laser-activated phthalocyanine loaded lipid nanoparticles targeting M2 macrophage for improved photoacoustic imaging-guided photothermal therapy.

The development of novel phototheranostic agents with significant potential in bioimaging-guided therapy is highly desirable for precise tumor therapy. Herein, NIR laser-activated ruthenium phthalocyanine (PcRu) loaded sub-30 nm targeting lipid nanoparticles (α-PcRu-NPs) were fabricated for photoacoustic imaging (PAI)-guided photothermal therapy (PTT). Due to the formation of J-type aggregation of PcRu in the core of the nanostructure, the α-PcRu-NPs exhibited high stability, efficient NIR absorption, reduced singlet oxygen generation, high photothermal activity, and intense photoacoustic signal. With the M2 macrophage target peptide (M2pep) modification and small size of α-PcRu-NPs, in vivo evaluations reveal that α-PcRu-NPs can specifically target and deeply penetrate the tumor foci. Under a high contrast PAI guidance with α-PcRu-NPs (744 nm, 0.35 µW), it also realizes superior photothermal therapy (PTT) for breast cancer under 670 nm laser irradiation (0.5 W/cm2). The prominent therapeutic efficacy of α-PcRu-NP-based PTT not only directly kills tumor cells, but also enhances the immune response by promoting dendritic cell maturation and increasing cytotoxic T cell infiltration. Thus, this work broadens the applications of phthalocyanine derivatives as phototheranostics in the PAI-guided PTT field.

Facile Method to Obtain Functionalised η6-Bound Arenes in Ru(II) and Os(II) Half-Sandwich Complexes.

Half-sandwich Ru(II)- and Os(II)-arene complexes have great potential for catalytic and biological applications. The possibility of fine-tuning their chemical reactivity by including modifications in the ligands around the metal adds to their many advantages. However, structural modifications at the n6-bound arene have had significant synthetic limitations, particularly in the design of Os(II)-tethered complexes. For the first time, we have employed a practical C(sp3)-C(sp2) coupling to obtain 28 new Ru(II) and Os(II) η6-arene half-sandwich complexes with a wide variety of arene functionalities, including those that enable the formation of tether rings, such as quinoline and coumarin. The introduction of novel functional groups at the arene in Ru(II)- and Os(II) half-sandwich complexes can broaden the synthetic scope of this type of organometallic complexes, and help to take full advantage of their structural diversity, especially in intracellular catalysis.

Oxidation of 5-hydroxymethylfurfural into 2,5-diformylfuran on alkali doped Ru/C catalysts. Electron properties of Ruthenium species as descriptor of catalytic activity.

Selective aerobic oxidation of 5-hydroxymethylfurfural into 2,5-diformylfuran has been achieved on alkali doped Ru/C catalyst. Optimization of Ru metal nanoparticles, as well as the nature and amount of the alkali dopant have been performed. The results showed that doping the Ru/C catalyst with controlled amount of potassium increases the catalytic activity, 2.5 fold with respect to the non-doped sample. Spectroscopic studies showed that these differences in activity can be attributed to a different oxidation reaction mechanism associated to the presence of electron rich Ru species in the promoted sample that facilitate the dissociation of O2, while prevents the oxidation of the metal. The Ru/C-K doped catalyst resulted very stable against leaching and metal sintering, being possible the reuse over several consecutive runs. Moreover, the catalyst could be successfully applied to the oxidation of different alcohols.

Ultrafast Quasi-Solid-State Microwave Construction of Spongy Cobalt-Molybdenum Phosphide for Hydrogen Production Over Wide pH Range.

The developed strategies for synthesizing metal phosphides are usually cumbersome and pollute the environment. In this work, an ultrafast (30 s) quasi-solid-state microwave approach is developed to construct cobalt-molybdenum phosphide decorated with Ru (Ru/CoxP-MoP) featured porous morphology with interconnected channels. The specific nanostructure favors mass transport, such as electrolyte bubbles transfer and exposing rich active sites. Moreover, the coupling effects between metallic elements, especially the decorated Ru, also act as a pivotal role on enhancing the electrocatalytic performance. Benefiting from the effects of composition and specific nanostructure, the prepared Ru/CoxP-MoP exhibits efficient HER performance with a current density of 10 mA cm-2 achieved in 1 m KOH, 0.5 m H2SO4, seawater containing 1 m KOH and 1 m PBS, with overpotentials of 52, 59, 55, 90 mV, and coupling with good stability. This work opens a novel and fast avenue to design metal-phosphide-based nanomaterials in energy-conversion and storage fields.

Ruthenium(II) complexes of curcumin and ß-diketone derivatives: effect of structural modifications on their cytotoxicity.

Ruthenium(II) complexes (Ru1-Ru3) with the general formula [Ru(O-O)(PPh3)2(bipy)]PF6, bearing two triphenylphosphine (PPh3), bipyridine (bipy) and a series of natural and synthetic ß-diketones (O,O) ligands were synthesized and characterized using various analytical techniques. The interaction between the complexes and calf thymus DNA (CT-DNA) was investigated and demonstrated a weak interaction. The cytotoxicity of the complexes was investigated against breast cancer cells (MDA-MB-231 and MCF-7), lung cancer cells (A549), cisplatin-resistant ovarian cancer cells (A2780cis), as well as non-tumour lung (MRC-5) and non-tumour breast (MCF-10A) cell lines. All complexes exhibited cytotoxic activity against all the cell lines studied, with half maximal inhibitory concentration (IC50) values ranging from 0.39 to 13 µM. Notably, the three complexes demonstrated selectivity against the A2780cis cell line, with IC50 ranging from 0.39 to 0.82 µM. Among them, Ru2 exhibited the highest cytotoxicity, with an IC50 value of 0.39 µM. Consequently, this new class of complexes shows good selectivity towards cisplatin-resistant ovarian cancer cells and it is promising for further investigation as anti-cancer agents.

Platinum-Ruthenium Bimetallic Nanoparticle Catalysts Synthesized Via Direct Joule Heating for Methanol Fuel Cells.

Platinum-Ruthenium (PtRu) bimetallic nanoparticles are promising catalysts for methanol oxidation reaction (MOR) required by direct methanol fuel cells. However, existing catalyst synthesis methods have difficulty controlling their composition and structures. Here, a direct Joule heating method to yield highly active and stable PtRu catalysts for MOR is shown. The optimized Joule heating condition at 1000 °C over 50 microseconds produces uniform PtRu nanoparticles (6.32 wt.% Pt and 2.97 wt% Ru) with an average size of 2.0 ± 0.5 nanometers supported on carbon black substrates. They have a large electrochemically active surface area (ECSA) of 239 m2 g-1 and a high ECSA normalized specific activity of 0.295 mA cm-2. They demonstrate a peak mass activity of 705.9 mA mgPt -1 for MOR, 2.8 times that of commercial 20 wt.% platinum/carbon catalysts, and much superior to PtRu catalysts obtained by standard hydrothermal synthesis. Theoretical calculation results indicate that the superior catalytic activity can be attributed to modified Pt sites in PtRu nanoparticles, enabling strong methanol adsorption and weak carbon monoxide binding. Further, the PtRu catalyst demonstrates excellent stability in two-electrode methanol fuel cell tests with 85.3% current density retention and minimum Pt surface oxidation after 24 h.

Synthesis, mol-ecular and crystal structure of [(NH2)2CSSC(NH2)2]2[RuBr6]Br2·3H2O.

The title compound, bis-[di-thio-bis-(formamidinium)] hexa-bromido-ruthenium dibromide trihydrate, [(NH2)2CSSC(NH2)2]2[RuBr6]Br2·3H2O, crystallizes in the ortho-rhom-bic system, space group Cmcm, Z = 4. The [RuBr6]2- anionic complex has an octa-hedral structure. The Ru-Br distances fall in the range 2.4779 (4)-2.4890 (4) Å. The S-S and C-S distances are 2.0282 (12) and 1.783 (2) Å, respectively. The H2O mol-ecules, Br- ions, and NH2 groups of the cation are linked by hydrogen bonds. The conformation of the cation is consolidated by intra-molecular O-H⋯Br, O-H⋯O, N-H⋯Br and N-H⋯O hydrogen bonds. The [(NH2)2CSSC(NH2)2]2+ cations form a hydrogen-bonded system involving the Br - ions and the water mol-ecules. Two Br - anions form four hydrogen bonds, each with the NH2 groups of two cations, thus linking the cations into a ring. The rings are connected by water mol-ecules, forming N-H⋯O-H⋯Br hydrogen bonds.

Dicarbonyl-1κ2 C-µ-chlorido-2:3κ2 Cl:Cl-penta-chlorido-2κ2 Cl,3κ3 Cl-[1(η6)-toluene]digallium(III)ruthenium(I)(Ru-Ga).

The title compound, [RuGa2Cl6(C7H8)(CO)2] or [(CO)2(GaCl2)(η6-toluene)Ru]+[GaCl4]-, was isolated from the reaction of Ga2Cl4 with di-phenyl-silanediol in toluene, followed by the addition of Ru3(CO)12. The compound contains a ruthenium-gallium metal-metal bond with a length of 2.4575 (2) Å.

(η6-Benzene)-chlorido-[(S)-2-(4-isopropyl-4,5-di-hydro-oxazol-2-yl)phenolato]ruthenium(II).

The title compound, [Ru(C12H14NO2)Cl(η6-C6H6)], exhibits a half-sandwich tripod stand structure and crystallizes in the ortho-rhom-bic space group P212121. The arene group is η6 π-coordinated to the Ru atom with a centroid-to-metal distance of 1.6590 (5) Å, with the (S)-2-(4-isopropyl-4,5-di-hydro-oxazol-2-yl)phenolate chelate ligand forming a bite angle of 86.88 (19)° through its N and phenolate O atoms. The pseudo-octa-hedral geometry assumed by the complex is completed by a chloride ligand. The coordination of the optically pure bidentate ligand induces metal centered chirality onto the complex with a Flack parameter of -0.056.

Rapid Synthesis of Ruthenium-Copper Nanocomposites as High-Performance Bifunctional Electrocatalysts for Electrochemical Water Splitting.

Development of high-performance, low-cost catalysts for electrochemical water splitting is key to sustainable hydrogen production. Herein, ultrafast synthesis of carbon-supported ruthenium-copper (RuCu/C) nanocomposites is reported by magnetic induction heating, where the rapid Joule's heating of RuCl3 and CuCl2 at 200 A for 10 s produces Ru-Cl residues-decorated Ru nanocrystals dispersed on a CuClx scaffold, featuring effective Ru to Cu charge transfer. Among the series, the RuCu/C-3 sample exhibits the best activity in 1 m KOH toward both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), with an overpotential of only -23 and +270 mV to reach 10 mA cm-2, respectively. When RuCu/C-3 is used as bifunctional catalysts for electrochemical water splitting, a low cell voltage of 1.53 V is needed to produce 10 mA cm-2, markedly better than that with a mixture of commercial Pt/C+RuO2 (1.59 V). In situ X-ray absorption spectroscopy measurements show that the bifunctional activity is due to reduction of the Ru-Cl residues at low electrode potentials that enriches metallic Ru and oxidation at high electrode potentials that facilitates the formation of amorphous RuOx. These findings highlight the unique potential of MIH in the ultrafast synthesis of high-performance catalysts for electrochemical water splitting.

Surface Acidic Species-Driven Reductive Amination of Furfural with Ru/T-ZrO2.

Catalyst development for upgrading bio-based chemicals towards primary amines has increasingly attracted owing to their applications in the pharmaceutical and polymer industries. The surface acidic sites in metal oxide-based catalysts play a key role in the reductive amination of aldehydes/ketones involving H2 and NH3; however, the crucial role of the type of surface acidic species and their strength remains unclear. Herein, this study exhibits the catalytic reductive amination of furfural (FUR) to furfurylamine (FUA) with Ru supported on tetragonal (Ru/T-ZrO2) and monoclinic (Ru/M-ZrO2) ZrO2. Ru/T-ZrO2 exhibited an 11.8-fold higher rate of reductive amination than Ru/M-ZrO2, giving a quantitative yield of FUA (99%) at 80 °C in 2.5 h and is recyclable up to four runs. Catalyst surface investigation using spectroscopic techniques, like X-ray photoelectron, electron paramagnetic resonance, and Raman, confirm higher oxygen vacancy sites (1.6 times) on the surface of Ru/T-ZrO2 compared to Ru/M-ZrO2. Moreover, in-situ NH3-diffuse reflectance infrared Fourier transform spectroscopy studies display that Ru/T-ZrO2 has more moderate Bronsted acidic sites (surface H-bonded hydroxyl groups) than Ru/M-ZrO2. Further, the controlled experiments and poisoning studies with KSCN and 2,6-lutidine suggest the crucial role of Ov sites (Lewis acidic sites) and surface hydroxyl groups (Bronsted acidic sites) for selective FUA formation.