Regulation of the PI3K/AKT/mTOR signaling pathway with synthesized bismuth oxide nanoparticles from Ginger (Zingiber officinale) extract: Mitigating the proliferation of colorectal cancer cells

In order to overcome the limitations of conventional therapeutic systems in the treatment of cancer, nanoparticles (NPs) have been rapidly produced and developed as a separate treatment method for control of cancer. Synthesis of nanoparticles using plant-based materials (green synthesis), due to the easy and cost-effective synthesis, production of non-toxic, sustainable and environmentally friendly products, can be considered the most appropriate method for preparation of NPs. In this study, after synthesis of Bi₂O₃ NPs using Ginger (Zingiber officinale) root (rhizome) extract, the synthesized NPs were characterized and their potential application as selective anticancer agents against HCT116 colorectal cancer cells was evaluated through regulation of PI3K/AKT/mTOR signaling pathway, whereas the human kidney (HK-2) cells were used as normal cells. FTIR analysis showed a band at 673 cm^?1 attributed to Bi-O vibration with a fingerprint region at 1291 cm^?1 demonstrating the attachment of the organic molecules to the synthesized Bi₂O₃ NPs. UV–visible study showed a λ_max of around 268 nm, whereas XRD analysis showed eight clear peaks, demonetizing the crystalline phase of synthesized Bi₂O₃ NPs. TEM analysis showed that spherical-shaped Bi₂O₃ NPs have a size range of 20–50 nm with a man size of around 35 nm. Finally, DLS analysis determined that Bi₂O₃ NPs have a hydrodynamic size of about 71.19 nm (PDI of 0.179) and a zeta potential value of ?44.39 mV, revealing the good colloidal stability of NPs. Cellular assays (MTT, LDH, flow cytometry, and RT-qPCR) showed that synthesized Bi₂O₃ NPs selectively induced anticancer effects against HCT116 colorectal cancer cells through membrane leakage, generation of ROS, induction of apoptosis via dysregulation of Bax, Bcl-2 and caspase-3 at mRNA level mediated via regulation of PI3K/AKT/mTOR signaling pathway. In conclusion, it may be suggested that the presence study could provide useful information for the potential anticancer effects mediated by synthesized Bi₂O₃ NPs in vitro, although further studies, including in vivo studies and clinical trials, are needed to support our findings.     

Three pairs of enantiomers bearing mitochondria‐targeted TPP+ groups as potential anti‐cancer agents

Six complexes with chiral Schiff‐base ligands containing TPP⁺ groups, [VO L ^R,R/^S,S](ClO₄)₂( 1 for RR, 2 for SS), [Ni L ^R,R/S,S](ClO₄)₂·C₂H₅OH ( 3 for RR, 4 for SS) and [CuL^R,R/S,S](ClO₄)₂·CHCl₃·CH₃CH₂OH ( 5 for RR, 6 for SS) ( L ^R,R/S,S = N,N′‐Bis{5‐[(triphenylphosphonium)‐methyl]salicylidine}‐(1R,2R/1S,2S)‐diphenylethane‐1,2‐diamine, were synthesized to serve as mitochondrion‐targeting anticancer drugs. The introduction of TPP⁺ group(s) might markedly influence the properties of complexes. Compounds 3 and 5 were structurally characterized by X‐ray crystallography. Complexes 1–6 could be moderate intercalating agents to CT‐DNA which is determined by several spectroscopy methods. DNA cleavage experiments revealed that all compounds could promote oxidative cleavage of pBR322 plasmid DNA in the presence of H₂O₂. MTT assay indicated 1–6 exhibited effective cytotoxicity on A549 and MCF‐7 cell lines. Notably, the IC₅₀ values of 5 (1.24 ± 0.33 μM) or 6 (1.47 ± 0.52 μM) were approximately 9–11 fold lower than that of cisplatin (IC₅₀ = 13.56 ± 0.88 μM) on A549 cells. 5 and 6 were picked for further study, which indicated that the cytotoxicity seems to result from multiple mechanisms of action, including effectively suppress the growth and proliferation of A549 cells, generation of reactive oxygen species, dissipation of mitochondrial membrane potential, cell cycle perturbation and apoptosis induction. Compounds 1–6 could highly accumulate in the mitochondria by means of ICP‐MS assay. This study demonstrates that 1–6 with mitochondrion‐targeting function could be efficient anticancer drugs.     

Synthesis,Nematicidal Activity,and 3D‐QSAR of Novel 1,3,4‐Oxadiazole/ Thiadiazole Thioether Derivatives

Forty one novel 1,3,4‐oxadiazole/thiadiazole thioether derivatives containing phenoxy moiety were designed and synthesized. Bioassay demonstrated that some of them showed remarkable activities against Tylenchulus semipenetrans in vitro and in vivo. Compounds 20 , 21 , 35 and 39 showed excellent lethal activities after treatment for 48 h in vitro, with LC₅₀ values of 13.4 ± 1.8, 11.7 ± 2.5, 13.7 ± 2.4 and 13.3 ± 1.1 mg·L^–1, respectively, which were obviously superior to fosthiazate (49.1 ± 2.8 mg·L^–1) and avermectin (26.6 ± 2.3 mg·L^–1). Compound 21 can effectively control the citrus nematode disease caused by T. semipenetrans at 200 mg·L^–1 in vivo with (68 ± 3)% inhibitory effect, which was even better than that of avermectin ((63 ± 2)%). The CoMFA and CoMSIA models of three‐dimensional quantitative structure‐activity relationships (3D‐QSARs) were established. The compound 33 was designed based on the 3D‐QSAR models with more vigorous nematicidal activities in vitro (LC₅₀ = 9.8 ± 1.4 mg·L^–1) and in vivo ((70 ± 5)%). These results demonstrated that compound 33 can be considered as a potential nematicide.     

Simple surface functionalization of magnetic nanoparticles with methotrexate-conjugated bovine serum albumin as a biocompatible drug delivery vehicle

Magnetic nanoparticles (MNPs) functionalized with methotrexate (MTX)-conjugated bovine serum albumin (BSA) as a biocompatible drug delivery vehicle were synthesized using a facile method. Characterization of the functionalized MNPs (Fe₃O₄@BSA-MTX NPs) was performed using various techniques including UV–visible spectroscopy, dynamic light scattering, vibrating sample magnetometry and X-ray diffraction. The particle size and zeta potential of Fe₃O₄@BSA-MTX NPs were 105.7 ± 3.81 nm (mean ± SD) and −18.2 mV, respectively. MTX release from Fe₃O₄@BSA-MTX NPs showed an enzyme-dependent release pattern. Hemo-biocompatibility of Fe₃O₄@BSA-MTX NPs was confirmed using hemolysis test. In addition, the cytotoxicity of functionalized MNPs and free MTX against MCF-7 cell line was investigated using MTT assay. The results of experiments revealed that the Fe₃O₄@BSA-MTX NPs as a biocompatible carrier could improve the therapeutic effect of MTX.     

Oxidation Responsive PEGylated Polyamino Acid Bearing Thioether Pendants for Enhanced Anticancer Drug Delivery

Reactive oxygen species (ROS) in biological tissues are in a state of dynamic balance. However, many diseases such as cancer and inflammation, are accompanied by a long-term increase in ROS. This situation inspires researchers to use ROS-sensitive nanocarriers for a site-specific release of cargo in pathological areas. Polyamino acid materials with good biodegradability, biocompatibility, and regular secondary structure are widely used in the biomedical field. Herein, a new oxidation responsive PEGylated polyamino acid is synthesised for anticancer drug delivery by ring-opening polymerisation of N-carboxyanhydrides bearing thioether pendants. The obtained block copolymer mPEG-b-PMLG self-assembles into spherical nanoparticles (NPs) in water with diameter ≈68.3 nm. NMR measurement demonstrated that the hydrophobic thioether pendants in the NPs can be selectively oxidised to hydrophilic sulfoxide groups by H₂O₂, which will lead to the disassociation of NPs. In vitro drug release results indicated that the encapsulated Nile red is selectively released in the trigger of 10 mM H₂O₂ in PBS. Finally, anticancer drug doxorubicin (DOX) is encapsulated to the NPs, and the obtained NPs/DOX exhibits an improved antitumor efficacy in 4T1 tumour-bearing mice and lower cardiotoxicity than free DOX. These results indicates that the mPEG-b-PMLG NPs are promising for anticancer drug delivery.     

Electrochemical nanostructured biosensors: carbon nanotubes versus conductive and semi-conductive nanoparticles

The aim of this work was to demonstrate that various types of nanostructures provide different gains in terms of sensitivity or detection limit albeit providing the same gain in terms of increased area. Commercial screen printed electrodes (SPEs) were functionalized with 100 µg of bismuth oxide nanoparticles (Bi₂O₃ NPs), 13.5 µg of gold nanoparticles (Au NPs), and 4.8 µg of multi-wall carbon nanotubes (MWCNTs) to sense hydrogen peroxide (H₂O₂). The amount of nanomaterials to deposit was calculated using specific surface area (SSA) in order to equalize the additional electroactive surface area. Cyclic voltammetry (CV) experiments revealed oxidation peaks of Bi₂O₃ NPs, Au NPs, and MWCNTs based electrodes at (790 ± 1) mV, (386 ± 1) mV, and (589 ± 1) mV, respectively, and sensitivities evaluated by chronoamperometry (CA) were (74 ± 12) µA mM^?1 cm^?2, (129 ± 15) ±A mM^?1 cm^?2, and (54 ± 2) ±A mM^?1 cm^?2, respectively. Electrodes functionalized with Au NPs showed better sensing performance and lower redox potential (oxidative peak position) compared with the other two types of nanostructured SPEs. Interestingly, the average size of the tested Au NPs was 4 nm, under the limit of 10 nm where the quantum effects are dominant. The limit of detection (LOD) was (11.1 ± 2.8) ±M, (8.0 ± 2.4) ±M, and (3.4 ± 0.1) ±M for Bi₂O₃ NPs, Au NPs, and for MWCNTs based electrodes, respectively.     

Development and validation of a HPLC–UV based method for the extraction and quantification of methotrexate in the skin

An innovative and sensitive HPLC–UV method for the extraction and quantification of methotrexate (MTX) in skin layers was developed and validated. Owing to the physico-chemical characteristics of the drug and the nature of the tissue, it was necessary to use folic acid (FA) as an internal standard for MTX quantification in the dermis. MTX (and FA) analysis was performed on a Phenomenex Jupiter C₁₈ column, using a 50 mm sodium acetate buffer (pH 3.6) and methanol mixture (87:13, v/v) as mobile phase, pumped at 1 ml/min. The absorbance was monitored at 290 nm. The method was selective, linear in the range 0.11–8.49 μg/ml for extraction solvent and 0.05–8.94 μg/ml for pH 7.4 phosphate-buffered saline, precise and accurate, with lower limits of quantitation of 0.11 μg/ml (extraction solvent) and 0.05 μg/ml (pH 7.4 phosphate-buffered saline). The method developed is suitable for the quantification of MTX in skin layers at the end of in vitro permeation experiments; the overall mass balance was 96.5 ± 1.4%, in line with the requirements of the Organisation for Economic Co-operation and Development guideline for the testing of the chemicals (Skin absorption: in vitro method).     

Organometallic assembling of chitosan‐Iron oxide nanoparticles with their antifungal evaluation against Rhizopus oryzae

The ever‐increasing resistance of plant microbes towards fungicides and bactericides has been causing serious threat to plant production in recent years. For the development of an effective antifungal agent, we introduce a novel hydrothermal protocol for synthesis of chitosan iron oxide nanoparticles (CH‐Fe₂O₃ NPs) using acetate buffer of low pH 5.0 for intermolecular interaction of Fe₂O₃ NPs and CH. The composite structure and elemental elucidation were carried out by using X‐ray power diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X‐ray (EDX), Transmission Electron Microscopy (TEM), Fourier Transformed Infrared Spectroscopy (FTIR) and Ultraviolet Visible Absorption Spectroscopy (UV–vis spectroscopy). Additionally, antifungal activity was evaluated both In vitro and In vivo against Rhizopus oryzae which is causing fruit rot disease of strawberry. We compared different concentrations (0.25%, 0.50%, 075% and 1%) of CH‐Fe₂O₃ NPs and 50% synthetic fungicide (Matalyxal Mancozab) to figure out suitable concentration for application in the field. XRD analysis showed a high crystalline nature of the NPs with average size of 52 nanometer (nm). SEM images revealed spherical shape with size range of 50–70 nm, whereas, TEM also revealed spherical shape, size ranging from 0 nm to 80 nm. EDX and FTIR results revealed presence of CH on surface of Fe₂O₃ NPs. The band gap measurement showed peak 317–318 nm for bare Fe₂O₃ NPs and CH‐Fe₂O₃ NPs respectively. Antifungal activity in both In vitro and In vivo significantly increased with increase in concentration. The overall results revealed high synergetic antifungal potential of organometallic CH‐Fe₂O₃ NPs against Rhizopus oryzae and suggest the use of CH‐Fe₂O₃ NPs against other Phyto‐pathological diseases due to biodegradable nature.     

Synthesis and Characterization of the Ternary Thiobismuthates A9Bi13S24 (A = K,Rb)

Ternary alkali metal thiobismuthates A₉Bi₁₃S₂₄ (A = K, Rb) were synthesized by direct combination reactions at 650 °C. The compounds crystallize in the monoclinic space group C2/m (no. 12) with cell parameters a = 30.919(1) Å, b = 4.1008(2) Å, c = 20.9072(9) Å, β = 105.826(3)° for K₉Bi₁₃S₂₄ ( 1 ) and a = 31.823(6) Å, b = 4.1177(8) Å, c = 21.086(4) Å, β = 105.62(3)° for Rb₉Bi₁₃S₂₄ ( 2 ). The crystal structure of 1 contains a 3D [K₂Bi₁₃S₂₄]^7– polyanionic framework, whereas 2 consists of 2D [RbBi₁₃S₂₄]^8– polyanionic slabs stacked along [201]. Both 1 and 2 are semiconductors with a band gap of 1.4 and 1.3 eV, respectively, which is supported by an electronic structure calculation. 1 melts congruently at 580 °C, while 2 melts incongruently at 575 °C. 1 and 2 are airstable and insoluble in water and organic solvents.     

BSA mediated Ag@Bi2S3 composites: synthesis,characterization, photodegradation of mixed dyes via metal-semiconductor interface,antimicrobial and antioxidant activities

Nowadays, the development of metal-metal sulfide interface semiconductors using green approach is best material for the photocatalytic and biological applications. Here, we provided for the first time, an environmentally friendly route to fabricate bovine serum albumin (BSA) assisted Ag@Bi₂S₃ composites through a metal-metal sulphide interface via a simple hydrothermal method for the evaluation of photochemical and biological applications. The synthesized composites were characterized by UV–vis DRS, PL, XRD, TEM, and N₂ adsorption-desorption isotherms. The UV–vis DRS and PL spectra show that the obtained nano-sized Ag@Bi₂S₃ composite displays enhanced visible-light absorption and a decreased fluorescence emission compared to that of Bi₂S₃ nanorods (NRs). The photocatalytic performances of the synthesized composites were evaluated by the degradation of the single (RhB and MB) and mixed dye (RhB+MB) under sunlight irradiation. The results indicated that the Ag@Bi₂S₃ composite exhibits superior photocatalytic activity (98.38%) than that of individual Ag NPs and Bi₂S₃ NRs due to the synergistic effect of Ag and Bi₂S₃ nanophases in the Ag@Bi₂S₃ composite, which results in an effective charge separation, fast electron transfer from Ag to Bi₂S₃, and a low recombination of photo-induced electron-hole pairs. The Ag@Bi₂S₃ composite also has good recycling stability up to 5 cycles and its mechanism also investigated. The evaluation of reactive species during the photocatalytic reaction was also carried out. Further, the effects of Bi₂S₃ and Ag NPs on the antimicrobial and antioxidant activity of the resultant Ag@Bi₂S₃ composite were also systematically investigated.     

Biological Applications of Synthesized ZnO Nanoparticles Using Pleurotus djamor Against Mosquito Larvicidal,Histopathology, Antibacterial,Antioxidant and Anticancer Effect

The present study pertained to biosynthesis, characterization and biomedical application (larvicidal, histopathology, antibacterial, antioxidant and anticancer activity) of Zinc oxide nanoparticles (ZnONPs) from Pleurotus djamor. The synthesized NPs were characterized using spectral and microscopic analyses and further confirmed by UV–Visible spectrophotometer with apeak of 350 nm. The ZnONPs showed strong antioxidant property (DPPH, H₂O₂ and ABTS⁺ radical assay) and expressed good larval toxicity against Ae. aegypti and Cx. quinquefasciatus (IVth instar larvae) with the least LC₅₀ and LC₉₀ values (10.1, 25.6 and 14.4, 31.7 mg/l) after 24 h treatment, respectively. We noticed the morphological changes (damaged anal papillae area and the cuticle layers) in the treated larvae. For the antibacterial assay, the highest growth inhibition zone was recorded in C. diphteriae (28.6?±?0.3 mm), followed by P. fluorescens (27?±?0.5 mm) and S. aureus (26.6?±?1.5 mm). The in vitro cytotoxicity assay depicted a significant level of cytotoxic effects (LC₅₀ values 42.26 μg/ml) of ZnONPs against the A549 lung cancer cells, even at low dose. The overall findings of the study suggest that P. djamor had the ability for the biosynthesis of ZnONPs and could act as an alternative biomedical agent for future therapeutic applications in medical avenues.

     

Enhanced photoelectrochemical performance of Bi2S3/Ag2S/ZnO novel ternary heterostructure nanorods

The current work investigates the morphology, crystallinity and photoelectrochemical (PEC) performance of bismuth sulfide/silver sulfide/zinc oxide nanorods (Bi₂S₃/Ag₂S/ZnO NRAs) photoelectrodes as prepared at different annealing temperature. ZnO NRAs was initially grown hydrothermally, deposited in sequence with Ag₂S and Bi₂S₃ via successive ionic layer adsorption and reaction (SILAR) method before undergoing the annealing treatment. The optimised photoelectrode (Bi₂S₃/Ag₂S/ZnO NRAs-400 °C) possesses an optical bandgap of 1.60 eV extending the absorption edge of ZnO to visible light spectrum. The current-voltage characterization of Bi₂S₃/Ag₂S/ZnO NRAs photoelectrodes revealed that the photocurrent density and photoconversion efficiency were strongly dependent on the annealing temperature. The PEC study shows that the photoelectrode annealed at 400 °C achieved impressive photocurrent density of 12.95 mA/cm² at +0.5 V (vs Ag/AgCl/saturated KCl) under 100 mW/cm² illumination with superior photoconversion efficiency of 12.63%. This improvement is due to the cascade-designed band structure alignment of Bi₂S₃/Ag₂S/ZnO/ITO and to the brilliant role of Ag₂S as an intermediate layer that reduced random chance of electron-hole (e⁻_-h⁺) pairs recombination and improved the electrons collection efficiency. This work is highly anticipated to give contribution on further utilisation of Bi₂S₃/Ag₂S/ZnO NRAs as a promising semiconductor material in PEC related applications.     

Electrochemical modification of Bi2S3 coatings in a nickel plating electrolyte

The electrochemical behavior of Bi₂S₃ coatings in Watts nickel plating electrolyte was investigated using the cyclic voltammetry, electrochemical quartz crystal microbalance, X-ray diffraction, and energy dispersive X-ray analysis methods. During the bismuth sulfide coating reduction in Watts background electrolyte in the potential region from −0.4 to −0.6 V, the Bi₂S₃ and Bi(III) oxygen compounds are reduced to metallic Bi, and the decrease in coating mass is related to the transfer of S²⁻ ions from the electrode surface. When the bismuth sulfide coating is reduced in Watts nickel plating electrolyte, the observed increase in coating mass in the potential region −0.1 to −0.4 V is conditioned by Ni²⁺ ions reduction before the bulk deposition of Ni, initiated by Bi₂S₃. In this potential region, the reduction of Bi(III) oxygen compounds can occur. After the treatment of as-deposited bismuth sulfide coating in nickel plating electrolyte at E = −0.3 V, the sheet resistance of the layer decreases from 10¹³ to 500–700 Ω cm. A metal-rich mixed sulfide Ni₃Bi₂S₂–parkerite is obtained when as-deposited bismuth sulfide coating is treated in Watts nickel plating electrolyte at a potential close to the equilibrium potential of the Ni/Ni²⁺ system and then annealed at temperatures higher than 120 °C.     

Synthesis,anticancer evaluation,and molecular modeling study of new 2-(phenylamino)pyrazolo[1,5-a]pyrimidine analogues

The reaction of 3-amino-5-phenylaminopyrazoles 2 with 3-(dimethylamino) acrylonitrile derivatives resulted in a series of substituted pyrazolopyrimidine analogues 4 and 6. The DFT studies of the isolated compounds showed that the frontier molecular orbitals energy gap was close and in the 2.65–2.81 eV range where the derivative 6b has the lowest and both of 4a and 4c have the highest values. Meanwhile, the anticancer activity of the newly synthesized pyrazolopyrimidine analogues have been tested against several different cell lines (MCF-7, PC3, Hep-2 and WI38). The investigated pyrazolopyrimidines showed remarkable cytotoxicity activity against the MCF-7 and Hep-2 cell lines. In comparison to the effects of 5-fluorouracil, IC₅₀ = 10.19 ± 0.42 and 7.19 ± 0.47, compounds 6a-c demonstrated potential anticancer activity with IC₅₀ values for MCF-7 (10.80 ± 0.36–19.84 ± 0.49 μM) and Hep-2 (8.85 ± 0.24–12.76 ± 0.16 μM). Important details regarding the protein's binding sites were disclosed when the produced analogues docked with the crystal structure of the KDM5A protein, which was located in the protein data library.     

Experimentally determined thermodynamic properties of schapbachite (α-AgBiS2) below T = 700 K

Thermodynamic properties of schapbachite (α-AgBiS₂) in the phase assemblage α-AgBiS₂–AgBi₃S₅–Bi have been studied by an EMF-technique. The EMF-measurements were made on the galvanic cell Pt(−)|Ag|AgI|AgBiS₂ + AgBi₃S₅ + Bi|C|Pt(+), over the temperature range from (429 to 699) K. According to the EMF vs. temperature relations obtained, the enthalpy of the phase transformation from β-AgBi_1+xS₂ to α-AgBi_1+xS₂, at T = (465.55 ± 5) K, was calculated to be (7.3 ± 2.1) kJ · mol⁻¹. New experimentally determined thermodynamic properties of the bismuth-saturated schapbachite (α-AgBi_1+xS₂), for each temperature region of the stable phases Bi(s) and Bi(l), were generated and analysed in detail. Based on the experimental results, Gibbs free energies of sulfidation reactions including Ag, Bi(l), S₂(g), Ag₂S and Bi₂S₃ to produce the bismuth-saturated schapbachite (α-AgBi_1+xS₂) have been evaluated. It has been observed that within the temperature range from (474 to 680) K, schapbachite saturated with bismuth (α-AgBi_1+xS₂) is thermodynamically more stable than the stoichiometric schapbachite (α-AgBiS₂).     

Triazole‐based ligands functionalized silica: Effects of ligand denticity and donors on catalytic oxidation activity of Pd nanoparticles

Triazole‐based ligands, tris (triazolyl)methanol (Htbtm), bis (triazolyl)‐phenylmethanol (Hbtm), and phenyl (pyridin‐2‐yl)(triazolyl)methanol (Hpytm), with differences in ligand denticity (i.e., bidentate and tridentate) and type of N donors (i.e., triazole and pyridine) were functionalized onto a silica support to produce the corresponding SiO₂‐ L ( L  = tbtm, btm, pytm). Subsequent reactions with Pd (CH₃COO)₂ in CH₂Cl₂ yielded Pd/SiO₂‐ L . ICP‐MS reveals that Pd loadings are higher with increased N loadings, resulting in the following trend: Pd/SiO₂‐tbtm (0.83 mmol Pd g^?1) > Pd/SiO₂‐btm (0.65 mmol Pd g^?1) ~ Pd/SiO₂‐pytm (0.63 mmol Pd g^?1). Meanwhile, TEM images of the used Pd/SiO₂‐ L catalysts after the first catalytic cycle show that the mean size of Pd NPs is highest with Pd/SiO₂‐pytm (8.5 ± 1.5 nm), followed by Pd/SiO₂‐tbtm (6.4 ± 1.6 nm) and Pd/SiO₂‐btm (4.8 ± 1.3 nm). Based on TONs, catalytic studies toward aerobic oxidation of benzyl alcohol to benzaldehyde at 60 °C in EtOH showed that Pd/SiO₂‐pytm possessed the most active surface Pd(0) atoms, most likely as a result of more labile properties of the pyridine–triazole ligand compared to tris‐ and bis (triazolyl) analogs. ICP‐MS and TEM analysis of Pd/SiO₂‐btm indicate minimal Pd leaching and similar average Pd NPs sizes after 1^st and 5^th catalytic runs, respectively, confirming that SiO₂‐btm is an efficient Pd NPs stabilizer. The Pd/SiO₂‐btm catalyst was also active toward aerobic oxidation of various benzyl alcohol derivatives in EtOH and could be reused for at least 7 reaction cycles without a significant activity loss.     

Facile Synthesis of Ultra‐wide Two Dimensional Bi2S3 Nanosheets: Characterizations,Properties and Applications in Hydrogen Peroxide Sensing and Hydrogen Storage

The ultra‐wide two dimensional Bi₂S₃ nanosheets (2D Bi₂S₃ Ns) as non‐toxic graphene‐like nanomaterials have been prepared through solvothermal decomposition of a single‐source precursor, Bi(S₂CNEt₂)₃, in ethylenediamine media for 2 h in 180 °C. The morphology, structure, properties and catalytic activity of prepared 2D Bi₂S₃ Ns were characterized with XRD, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV‐Visible spectroscopy, cyclic voltammetry (CV), amperometry, electrochemical charge/discharge technique and electrochemical impedance spectroscopy (EIS). The SEM image showed the 2D Bi₂S₃ Ns with a thickness of 15±4 nm and lengths of several micrometers is synthesized. The UV−Vis spectrum of 2D Bi₂S₃ Ns showed high sensitivity to visible‐near infrared light with its direct energy band gap of ≈1.22 eV. These Bi₂S₃ Ns showed high electron transfer ability and good electrochemical behavior and also exhibited electro‐catalytic activity toward the reduction‐oxidation of hydrogen peroxide. It is found that Bi₂S₃ Ns could detect H₂O₂ at wide linear concentration range (50.0 μM–8.0 mM) with detection limit 8 μM, using amperometry as measuring technique. Also the synthesized Bi₂S₃ Ns exhibited excellent electrochemical H₂ storage properties. As a result, based on above properties, the Bi₂S₃ Ns can be used as a valuable and useful nanomaterial for H₂ storage, high‐energy batteries, electrocatalytic fields and electrochemical sensing.     

Green synthesis of iron (Fe) nanoparticles using Plumeria obtusa extract as a reducing and stabilizing agent: Antimicrobial,antioxidant and biocompatibility studies

In the current study, a green and facile route for the synthesis of iron nanoparticles (FeNPs) was adopted. The FeNPs were fabricated via a single step green route using aqueous leaves extract of Plumeria obtusa (P. obtusa) as a capping/reducing and stabilizing agents. The FeNPs were characterized by UV/Vis (Ultraviolet/Visible), FTIR (Fourier Transform Infra-Red spectroscopy), TEM (Transmission Electron Microscopy), SEM (Scanning Electron Microscopy) and XRD (X-Ray Diffraction) techniques. The FeNPs were of spheroidal shape with average size of 50 nm. The biosynthesized FeNPs were further evaluated for their biological activities like antimicrobial, antioxidant and biocompatibility. The FeNPs displayed auspicious antimicrobial activity against bacterial (E. coli, B. subtilis) and fungal strains (A. niger) and S. commune. The test performed against red blood cells (RBCs) lysis (1.22 ± 0.02%) and macrophage (31 ± 0.09%) showed biocompatible nature of FeNPs. In vitro cytotoxicity against AU565 (82.03 ± 0.08–23.65 ± 0.065%) and HeLa (88.61 ± 0.06–33.34 ± 0.06%) cell lines showed cell viability loss in dose dependent manner (FeNPs 25–100 μg/mL). The antioxidant activities values were determined through DPPH, TRPA, NO and H₂O₂ assays with values 70.23 ± 0.02%, 76.65 ± 0.02 μg AAE/mg, 74.43 ± 0.04% and 67.34 ± 0.03%, respectively. Based on the bioactivities, the green synthesized FeNPs have potential for therapeutic applications.     

CCQM-P111 study on traceable determination of practical salinity and mass fraction of major seawater components

The first part of the study assessed the equivalence of practical salinity measurement results of a slightly diluted seawater sample from the North Atlantic, which were traceable to the SI. The study shows that the practical salinity reference value S _RV (here S _RV = 34.967) can be determined with a relative standard uncertainty of 3×10⁻⁴. This quantifies the uncertainty range, in which long-term comparability of practical salinity measurement results can be guaranteed currently. In the second part of the study, eight laboratories determined the mass fractions of five seawater components to quantify the equivalence of these measurement results. The results were: Na⁺ (10.726 ± 0.134) g/kg, Mg²⁺ (1.288 ± 0.018) g/kg, Sr²⁺ (0.00755 ± 0.00011) g/kg, Cl⁻ (19.360 ± 0.047) g/kg, SO₄ ²⁻ (2.650 ± 0.025) g/kg. The investigation confirmed the reference composition mass fractions of sodium, magnesium and chloride ions, but it showed a disagreement for strontium and sulphate ions.     

Scalable one-pot synthesis of bismuth sulfide nanorods as an electrode active material for energy storage applications

The quest for developing the scalable methods of synthesis of materials with potential electrochemical energy storage applications remains a great challenge. Herein, we propose a facile, one-step chemical precipitation method for the synthesis of Bi₂S₃ with the nanorods morphology. Influence of different synthesis temperatures on the physical, chemical, and electrochemical performance was investigated. Relatively low BET surface area and mesopore volume of Bi₂S₃ increased with the higher reaction temperature. Bismuth sulfides synthesized at various temperatures were used as an electrode active material in supercapacitor. The semiconductive properties of Bi₂S₃ resulted in exceptional capacitive behavior. Bismuth sulfide synthesized at 75 °C exhibited a specific capacitance of 457 F g⁻¹ at 1 A g⁻¹ in 6 mol L⁻¹ KOH solution as an electrolyte. Moreover, material prepared at 75 °C maintained the best capacitance value at a large current density of 20 A g⁻¹, compared with bismuth sulfides synthesized at the temperatures of 0 °C and 25 °C.