TEM Data Research Articles

Design, synthesis, and applications of pyrene-quinoline based cell-permeable AIEgen for cellular imaging and antibacterial activity

Herein, we describe the design and synthesis of PyQ, a novel pyrene-quinoline based cell-permeable aggregation-induced emission luminogen (AIEgen) with implications in cellular imaging and antibacterial activity. The synthesised compound was characterised by NMR, HR-MS and IR studies. PyQ exhibited AIE in the DMSO-water mixture and this was confirmed by fluorescence spectroscopic studies. The addition of water to the DMSO solution of PyQ resulted in enhanced fluorescence emission for up to 70% water in DMSO. The SEM and TEM data also confirmed the aggregate formation in addition to DLS, quantum yield and lifetime measurements. The synthesised AIE compound was found to be non-toxic and cell-permeable that could readily label the cytoplasm and plasma membrane. Of note, PyQ exhibited both blue and green emission inside the cell. We further evaluated the antibacterial activity of PyQ aggregates against the model Gram-negative bacteria, Escherichia coli (E. coli) using the standard colony forming unit (CFU) counting assay. The results suggest that the aggregates were potent antibacterial agents and the SEM data clearly showed the disruption of the bacterial membrane. Taken together, this work provides a simple and efficient technique for the development of an AIEgen with antibacterial activity as well as rapid cellular imaging with both blue and green emission.

Study on the microstructure evolution mechanism of copper single phase alloys under deep undercooling conditions

This article mainly used the deep undercooling technology to treat Cu60Ni40, Cu60Ni38Co2, and Cu60Ni35Co5 alloys to obtain different undercoolings. By using high speed cameras, the rapid solidification process was recorded to analyze the relationship between its evolution law and the magnitude of undercooling. When observing its microstructure, it was also found that there was a critical undercooling degree throughout its entire solidification process. The influence of Co element addition on solidification rate, recalescence effect, and critical undercooling of copper based single-phase alloys under undercooling conditions was explored. EBSD analysis was conducted on the refined microstructure of the alloy that achieved the maximum undercooling, and the significance of grain orientation and orientation difference distribution was found. TEM tests were conducted on a Cu60Ni38Co2 alloy with a maximum undercooling of 259 K, and it was found that there are high-density dislocation networks in some areas within them. Finally, the Vickers hardness of the above alloys was measured and recorded using a microhardness tester (HVS-1000Z), and the evolution between microhardness and undercooling, as well as the changes in microhardness under critical undercooling, were analyzed. Based on the analysis of EBSD, TEM, and microhardness data above, it is found that grain refinement at high undercooling is dominated by recrystallization.

SYNTHESIS OF SILVER NANOPARTICLES IN THE PRESENCE OF HYPERBRANCHED OLIGOMERIC IONIC LIQUID AS THEIR SURFACE STABILIZER

A method for synthesis of silver nanoparticles (AgNPs) in the presence of proposed by us protic anionic oligomeric ionic liquid (OIL) of hyperbranched structure as a stabilizer of their surface was developed. Reduction of Ag(I) silver cations was carried out with trisodium citrate in an aqueous environment at temperature of 100°C for an hour. The OIL proposed and used by us as a surface stabilizer of colloidal AgNPs is a product of exhaustive acylation of hyperbranched oligoester polyol of the 3rd generation (contains 32 terminal primary aliphatic hydroxyl groups) with cyclic 2-sulfobenzoic anhydride and subsequent neutralization of the resulting sulfonic compound with N-methylimidazole. The synthesized AgNPs stabilized with the OIL are powders soluble in water that opens up wide possibilities of using the developed AgNPs to obtain nanodisperse systems, in particular hydrosols and nanocomposite functional polymer materials. The formation of «guest-host» type complexes between the OIL and silver ions Ag(I) and the adsorption of carbonyl and ionic (their cationic component) groups on the surface of the formed AgNPs were established by FTIR. According to FTIR data trisodium citrate is also partially adsorbed on the surface of the formed silver nanoparticles and takes part in complex formation. The formation of AgNPs was also confirmed by X-ray analysis. The X-ray diffractograms of the obtained AgNPs show reflections at 38.0, 44.2, 64.4 and 77.3°, which are correspondingly related to (111), (200), (220) and (311) reflections of crystal planes and indicates the formation of silver nanoparticles with a face-centered cubic structure. It should be noted that the intensity of the above-mentioned reflexes increases with an increase in amount of the OIL used in the synthesis that confirms the stabilizing effect of the OIL in relation to the AgNPs and favoring the formation of the last ones due to autoreduction of silver. X-ray data evidences presence of trisodium citrate in the composition of the AgNPs being absorbed on the surface or as the complex with silver ions. The formation of AgNPs is also confirmed by TEM data. The TEM micrograph shows nanosized spherical particles of the «core-shell» type, where according to FTIR and X-ray analys a reduced silver is the core, and the OIL and trisodium citrate forms the shell as a stabilizer. These nanoparticles form swarm-like structures. Analysis of the microphotograph showed that the obtained AgNPs are characterized by a narrow size distribution in the range of 5–10 nm. The synthesized AgNPs stabilized with OIL and trisodium citrate are powders soluble in water, which opens up wide possibilities of their use for obtaining highly dispersed systems, in particular hydrosols and nanocomposite functional polymer materials based on them.

Evaluation of Ibuprofen Prolonged Release of Biomedical PLA-PEG-PLA Hydrogel via Degradation Mechanism.

A micellar hydrogel has long been considered an intelligent hydrophobic drug delivery material. In this study, synthesized PLA1750-PEG1750-PLA1750 micellar hydrogel aims to encapsulate ibuprofen (IBU) in the core PLA hydrophobic of the micelle and prolong the drug release time by an injectable route. The structure and morphology of the PLA1750-PEG1750-PLA1750 copolymer hydrogel were demonstrated by 1H NMR and TEM data. The hydrogel also achieved a gel state at a high concentration of 25 wt.% under the physiological conditions of the body (37°C, pH 7.4). Besides, the biocompatibility test displayed that the hydrogel slightly affected mice after injection one week and fully recovered after four weeks. Furthermore, the in vitro degradation of the hydrogel showed apparent gel erosion after the first three weeks, which is related to the IBU release rate: slow for the first three weeks and then fast. As a result, the total drug release after three and four weeks was 18 wt.% and 41 wt.%, respectively. However, in the first 24 hours, the amount of the drug released was 10 wt.%, suggesting that the IBU drug diffused from the surface hydrogel to the buffer solution. These show that PLA1750-PEG1750-PLA1750 hydrogel can be a potential IBU drug delivery candidate.

Green synthesis of silver nanoparticles using hydroalcoholic root extract of Potentilla fulgens and evaluation of its cutaneous wound healing potential

The present study focuses on the green synthesis of silver nanoparticles (AgNPs) using hydro-alcoholic root extract of Potentilla fulgens and evaluation of its wound healing properties in the rat model. The dried roots of PF were refluxed in alcohol: water mixture (70:30) for 24 h and the extract were evaporated to dryness using a rotary evaporator. For the synthesis of AgNP-PF, different concentrations of the extract (1–5 mg) were allowed to react with different concentrations of silver nitrate (1–5 mM). The completion of the reaction was noted through color change from colorless to brown and this can be further confirmed using UV–visible spectroscopy. The optimized formulation was further characterized using DLS, TEM, EDX, FTIR, and XRD. The biosynthesized AgNP-PF were loaded into a topical carbopol gel and finally investigated for wound healing potential in experimental rats. Results revealed that the ratio of different concentrations of AgNO3 to plant extract significantly affected the particle size, shape, yield and stability of the AgNP-PF. A UV–visible absorption band of 410–440 nm indicated the synthesis of AgNP-PF. TEM data with a size range of 10–20 nm showed that the AgNP-PF were spherical in shape. FTIR revealed the presence of -OH group responsible for the reduction and stabilization, while XRD confirmed the crystallinity of the AgNP-PF. Topical AgNP-PF gel showed promising wound healing property with significant wound contraction in experimental rats. In conclusion, stable silver nanoparticles were successfully formulated by green synthesis and loaded efficiently for efficient wound healing.

Influence of Pre-Milling on the Mn Solid Solubility in the Al-Mn-Cu Alloy during Mechanical Alloying

Increasing the strength of Al-based alloys is an important issue of physical metallurgy and industrial processing. Severe plastic deformation and related extension of solid solubility during mechanical alloying provide an opportunity for significant strengthening due to grain refinement, solid solution, and precipitation strengthening mechanisms. During mechanical alloying, an anomalous increase in the solid-state solubility of alloying elements occurs. The present study focuses on the investigation of the pre-milling treatment to the microstructure, phase composition, and solubility in Al-7.7 Mn-3.5 Cu (wt%) alloy processed by a high-energy ball milling of Al-14.3 Mn-6.5 Cu (wt%) master alloy diluted with Al powder. During milling, the mean granular size decreased to ~5 µm, and a strong grain refinement occurred. According to our TEM and XRD data, ball milling provided a mean grain size of 13–14 nm and a microhardness of 490–540 HV. The lattice parameter of the Al-based solid solution decreased with an increase in the milling time to 7.5–10 h, which suggested the dissolution of the alloying elements, and the lattice parameter increased at a higher milling time of 12.5–40 h, which suggested the decomposition of the solid solution. The XRD data revealed the dissolution of the Al6Mn and Al20Cu2Mn3 solidification-originated phases with a further precipitation of the Al6Mn dispersoids. Pre-milling of the master alloy entailed a significant decrease in the minimal lattice parameter value from 0.4029 nm to 0.4023 nm due to an increase in the Mn solute content from 6.2 wt% (3.3 at%) to 7.5 wt % (4.0 at%) in the studied alloy during high-energy ball milling.

Ru-Ba/ANF catalysts for ammonia decomposition: Support carbonization influence

The study of ruthenium catalysts for ammonia decomposition on carbonized and non-carbonized Al2O3 nanofibers (ANF) showed that the activity of catalysts with carbonized supports (ANFC) was 2–3 times higher compared to non-carbonized ones. Thus, on Ru/ANFC and Ru/ANF the release of hydrogen reached 133.5 and 34.7 mmol H2/(min·gcat), respectively, whereas on Ru-BaAc/ANFC and Ru-BaAc/ANF, only 118.8 and 58.6 mmol H2/(min·gcat), respectively. On the average, the activation energy of ammonia decomposition on ANFC-supported catalysts is 15 kJ/mol lower than that value for ANF-supported catalysts. According to TEM data, Ru particles on ANFC are larger than on ANF, but are more evenly distributed. An increase in the activity of the catalyst correlates with a change in the electronic state of the active component. XPS data for Ru indicate a shift in the binding energy towards lower values when going from ANF to ANFC.

Exploitation of metal-organic framework/ polyaniline composite as an efficient transducer for potentiometric determination of epinastine hydrochloride

Due to their unique characteristics, such as varying pore diameters, crystalline organized structures, huge surface areas, and chemical tunability, metal-organic frameworks are now thought to be particularly potential modifiers in electrochemical analysis. In this study, polyaniline was successfully polymerized around the metal-organic framework NH2-MIL-53(Fe) to create a conductive transducer composite that was applied to design a potentiometric carbon paste electrode for the reliable detection of Epinastine hydrochloride (EP.HCl). FT-IR, XRD patterns, and TEM data support the creation of the synthesised NH2-MIL-53(Fe)/PANI composite and prove that PANI coated the surface of NH2-MIL-53(Fe). In optimal circumstances, the electrode has been efficiently used for monitoring EP.HCl in its pure form, ophthalmic preparation, and artificial aqueous humor. At a limit of detection of 7.5 × 10−8 mol L−1, the response signal of the CPE rose linearly in the concentration between 1 × 10−7 to 1 × 10−2 mol L−1. With no surface renewal for 15 weeks, the suggested sensor is marked by significant stability and selectivity.

Ligand-Mediated Control of the Surface Oxidation States of Copper Nanoparticles Produced by Laser Ablation

We report on studies that demonstrate how the chemical composition of the surface of copper nanoparticles (CuNPs) - in terms of percentage copper(I/II) oxides - can be varied by the presence of N-donor ligands during their formation via laser ablation. Changing the chemical composition thus allows systematic tuning of the surface plasmon resonance (SPR) transition. The trialed ligands include pyridines, tetrazoles, and alkylated tetrazoles. CuNPs formed in the presence of pyridines, and alkylated tetrazoles exhibit a SPR transition only slightly blue shifted with respect to CuNPs formed in the absence of any ligand. On the other hand, the presence of tetrazoles results in CuNPs characterized by a significant blue shift of the order of 50-70 nm. By comparing these data also with the SPR of CuNPs formed in the presence of carboxylic acids and hydrazine, this work demonstrates that the blue shift in the SPR is due to tetrazolate anions providing a reducing environment to the nascent CuNPs, thus preventing the formation of copper(II) oxides. This conclusion is further supported by the fact that both AFM and TEM data indicate only small variations in the size of the nanoparticles, which is not enough to justify a 50-70 nm blue-shift of the SPR transition. High-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) studies further confirm the absence of Cu(II)-containing CuNPs when prepared in the presence of tetrazolate anions.

In Situ Gel with Silver Nanoparticles Prepared Using Agrimonia eupatoria L. Shows Antibacterial Activity

Silver nanoparticles (Ag NPs) with antibacterial activity can be prepared in different ways. In our case, we used ecological green synthesis with Agrimonia eupatoria L. The plant extract was used with Ag NPs for the first time to prepare termosensitive in situ gels (ISGs). Such gels are used to heal human or animal skin and mucous membranes, as they can change from a liquid to solid state after application. Ag NPs were characterized with various techniques (FTIR, TEM, size distribution, zeta potential) and their antibacterial activity was tested against Staphylococcus aureus and Escherichia coli. In accordance with the TEM data, we prepared monodispersed spherical Ag NPs with an average size of about 20 nm. Organic active compounds from Agrimonia eupatoria L. were found on their surfaces using FTIR spectroscopy. Surprisingly, only the in situ gel with Ag NPs showed antibacterial activity against Escherichia coli, while Ag NPs alone did not. Ag NPs prepared via green synthesis using plants with medicinal properties and incorporated into ISGs have great potential for wound healing due to the antibacterial activity of Ag NPs and the dermatological activity of organic substances from plants.

Ceria–Zirconia-Supported Ruthenium Catalysts for Hydrogen Production by Ammonia Decomposition

Commercial cerium–zirconium oxide supports (Ce0.5Zr0.5O2, Ce0.75Zr0.25O2, and Ce0.4Zr0.5Y0.05La0.05O2) were used to prepare Ru/CeZrOx catalysts. According to the XRD and IR spectroscopy data, the supports consist of ceria-based substitutional solid solutions. The specific surface areas of supports and catalysts are similar and range from 71–89 m2/g. As shown by TEM and XRD methods, the size of support particles equals 6–11 nm. According to the TEM data, the size of ruthenium particles does not exceed 1.3 nm. The catalyst activity in the ammonia decomposition process was studied. The Ru/Ce0.75Zr0.25O2 catalyst at temperature 500 °C and GHSV 120,000 h−1 demonstrated the highest hydrogen productivity of 53.3 mmol H2/(gcat·min) and compares well with the best results reported in the literature. The kinetics of ammonia decomposition reaction were calculated using the Temkin–Pyzhov exponential expression. The developed mathematical model well described the experimental data. The studied catalysts demonstrated high activity for the ammonia decomposition reaction.

Efficacious Removal of Flonicamid Insecticide from Water by GO@functionalized Calix[4]pyrrole: Synergistic Effect in Adsorption

AbstractThe presence of a highly toxic pyridine carboxamide insecticide, namely flonicamid in water bodies poses a serious risk to both the aquatic ecosystem and human health. Therefore, a graphene oxide (GO) decorated with azo‐functionalized calix[4]pyrrole i. e. GO‐azocalix[4]pyrrole (GACP) was synthesized to study the removal of flonicamid insecticide through adsorption. The nano‐adsorbent was characterized by IR, XPS, TGA, Raman, SEM, and TEM data. The effect of concentration of flonicamid solution, contact time, adsorbent dosage, temperature, and pH was investigated in the batch adsorption process. Experimental data suggested that equilibrium was attained within 40 min and adsorption efficiency was 93.28 %. The synergistic effect of GO and azocalix[4]pyrrole played an important role in the adsorption. The Langmuir isotherm was followed and the maximum adsorption capacity was found to be 11.43 mg/g. The pseudo‐second‐order kinetic data was well obeyed and thermodynamic investigation suggested the feasible and spontaneous nature of flonicamid onto GACP nanocomposite.

Liposomal Iron Oxide Nanoparticles Loaded with Doxorubicin for Combined Chemo-Photothermal Cancer Therapy

Iron oxide nanoparticle (IONP) possesses unique advantages over other nanoparticles in the use of cancer imaging and therapy. Specifically, it has drawn great attention in the emerging research field of photothermal cancer therapy. Herein, we developed doxorubicin (DOX)-loaded liposomal IONP (Lipo-IONP/DOX) and evaluated in vitro and in vivo their applicability for combined chemo-photothermal cancer therapy. The Lipo-IONP was synthesized by the thin-film evaporation method. The prepared Lipo-IONP was observed as about a 240 nm-sized agglomerate of globular-shaped nanoparticles. The TEM and FT-IR data evidenced the successful formation of liposomal IONP. The superparamagnetic property of the Lipo-IONP was confirmed by the SQUID analysis. The DSC data showed a transition temperature of about 47-48 °C for the mixed lipids composing the Lipo IONP, and the DOX release studies revealed the feasibility of induced burst release of DOX by laser irradiation. The Lipo-IONP/DOX possessed a plasma half-life of 42 min, which could ensure sufficient circulation time for magnetic tumor targeting. The in vivo magnetic targeting enabled a significant increase (6.3-fold) in the tumor accumulation of Lipo-IONP/DOX, leading to greater photothermal effects. Finally, the preliminary efficacy study evidenced the applicability as well as the safety of the Lipo-IONP/DOX for use in combined chemo-photothermal cancer therapy. Overall, the study results demonstrated that the Lipo-IONP/DOX might serve as an effective and safe agent for combined chemo-photothermal cancer therapy.

Ultrastructure of a Mechanoreceptor of the Trichoid Sensilla of the Insect Nabis rugosus: Stimulus-Transmitting and Bio-Sensory Architecture.

This paper presents the ultrastructure morphology of Nabis rugosus trichoid sensilla using SEM and TEM data, along with a two-dimensional model of the trichoid sensilla developed in Amira software. The SEM images show the shape and scattering of the trichoid mechanosensilla over the N. rugosus flagellomere. The TEM images present the ultrastructural components, in which the hair rises from the socket via the joint membrane. The dendrite sheath is connected at the base of the hair shaft, surrounded by the lymph space and the socket septum. This dendrite sheath contains a tubular body with microtubules separated by the membrane (M) and granules (Gs). This study presents a model and simulation of the trichoid sensilla sensing mechanism, in which the hair deflects due to the application of external loading above it and presses the dendrite sheath attached to the hair base. The dendrite sheath is displaced by the applied force, transforming the transversal loading into a longitudinal deformation of the microtubules. Due to this longitudinal deformation, electric potential develops in the microtubule's core, and information is delivered to the brain through the axon. The sensilla's pivot point or point of rotation is presented, along with the relationship between the hair shaft length, the pivot point, and the electric potential distribution in the microtubules. This study's results can be used to develop ultra-sensitive, bioinspired sensors based on these ultrastructural components and their biomechanical studies.

SDS induces amorphous, amyloid-fibril, and alpha-helical structures in the myoglobin in a concentration-dependent manner

Amyloid fibrils have been linked to a number of diseases. Surfactants imitate plasma membrane lipids and induce amyloid fibrils. This study examined the effects of the anionic surfactant sodium dodecyl sulfate (SDS) at pH 4.5 on equine skeletal muscle myoglobin (E-Mb). To analyze the effect of SDS on aggregation and amyloid-fibril formation to E-Mb, we used various spectroscopic techniques (turbidity, light scattering, intrinsic fluorescence, ThT fluorescence, and circular dichroism (CD)), electrophoretic, and microscopic techniques. Turbidity, SDS-PAGE, and light scattering all indicated the formation of E-Mb aggregates at SDS concentrations ranging from 0.2 mM to 1.0 mM. In the presence of 0.4 mM SDS, far-UV CD and TEM data indicate that E-MB forms amorphous aggregates. ThT binding, Far-UV CD, and TEM findings indicate that E-Mb forms amyloid-like structures in the presence of 0.6–1.0 mM SDS. However, no aggregation was seen at SDS concentrations above 1 mM. In the presence of high SDS concentrations (> 1 mM), the E-Mb exhibited native-like α-helical structure. As a result, SDS exhibited three distinct behaviors: amorphous aggregates, amyloid-fibrils, and helix-inducer. These findings also shed light on how amyloid fibrils are formed when anionic surfactants are introduced, which is a significant takeaway.

Petrophysical substantiation of geological section elastic-velocity property recovery potential based on TEM data

The geological section of Eastern and Western Siberia (Russia) is a very complicated object for seismic exploration. The research presented in the article is aimed at studying a petrophysical relation between electrical resistivity and P-wave velocity, as a basis for predicting the velocity model of the upper part of the section based on TEM sounding. Having performed a numerical modeling of petrophysical function, the authors calculated the dependency curves of electrical resistivity on the P-wave velocity. The obtained results of mathematical modeling and field experiments have proved the effectiveness of the proposed methodology as it increases the accuracy of geological model construction and enhances prediction reliability. Based on the dependences obtained, conclusions were drawn about the geological conditions favorable for a steady transition of section geoelectric characteristics to the velocity ones. The proposed technology is shown to provide a reliable reconstruction of the velocity model of the upper part of the section. The use of the developed methodology allows to improve the quality of seismic data processing and increase the accuracy of geological section boundary mapping at minimum cost based on the nature of the problem under investigation.

Ultralow thermal conductivity and enhanced thermoelectric properties in a textured (Ca0.35Sr0.2Ba0.15Na0.2Bi0.1)3Co4O9 high-entropy ceramic

A novel layered (Ca0.35Sr0.2Ba0.15Na0.2Bi0.1)3Co4O9 high-entropy ceramic is prepared for the first time by the traditional solid-state reaction. The XRD, SEM-EDS and TEM data exhibit that the multi-component cations can be introduced into the Ca site to form a single-phase and homogeneous solid solution with highly preferential crystal orientation and multi-scale structural defects. The textured high-entropy ceramic, compared to the pristine Ca3Co4O9 sample, shows a significantly increased electrical conductivity due to the higher carrier mobility derived from the c-axis selective orientation, and obtains an enhanced power factor of 0.27 mW·m−1·K−2. Besides, high entropy induced multi-dimensional lattice defects can act as the phonon scattering centers to effectively suppress the lattice thermal conductivity, and achieves an ultralow thermal conductivity of 0.87 W·m−1·K−1 as well as a peak figure-of-merit of 0.3 at 973 K, which is about 2.5 times larger than that of Ca3Co4O9. Our work deeply reveals the impact of the microstructure on thermoelectric properties in a high-entropy ceramic, which may help to advance the understanding and design of high-entropy thermoelectric materials.

The in vitro and in vivo anticancer activities of Antrodia salmonea through inhibition of metastasis and induction of ROS-mediated apoptotic and autophagic cell death in human glioblastoma cells

Background:Antrodia salmonea (AS) exhibits anticancer activities against various cancers. ObjectiveThis study investigated the anticancer activities of AS on human glioblastoma (GBM8401 and U87MG) cells both in vitro and in vivo and explained the underlying molecular mechanism. MethodsMTT, colony formation, migration/invasion assay, immunoblotting, immunofluorescence, TUNEL, Annexin V/PI staining, AO staining, GFP-LC3 transfection, TEM, qPCR, siLC3, DCFH2-DA assay, and xenografted-nude mice were used to assess the potential of AS therapy. ResultsAS treatment retarded growth and suppressed colony formation in glioblastoma cells. AS attenuates EMT by suppressing invasion and migration, increasing E-cadherin expression, decreasing Twist, Snail, and N-cadherin expression, and inhibiting Wnt/β-catenin pathways in GBM8401 and U87MG cells. Furthermore, AS induced apoptosis by activating caspase-3, cleaving PARP, and dysregulating Bax and Bcl-2 in both cell lines. TUNEL assay and Annexin V/PI staining indicated AS-mediated late apoptosis. Interestingly, AS induced autophagic cell death by LC3-II accumulation, AVO formation, autophagosome GFP-LC3 puncta, p62/SQSTM1 expression, and ATG4B inhibition in GBM8401 and U87MG cells. TEM data revealed that AS favored autophagosome and autolysosome formation. The autophagy inhibitors 3-MA/CQ and LC3 knockdown suppressed AS-induced apoptosis in glioblastoma cells, indicating that the inhibition of autophagy decreased AS-induced apoptosis. Notably, the antioxidant N-acetylcysteine (NAC) inhibited AS-mediated ROS production and AS-induced apoptotic and autophagic cell death. Furthermore, AS induced ROS-mediated inhibition of the PI3K/AKT/mTOR signaling pathway. AS reduced the tumor burden in GBM8401-xenografted nude mice and significantly modulated tumor xenografts by inducing anti-EMT, apoptosis, and autophagy. AS could be a potential antitumor agent in human glioblastoma treatment.

Degradation of the dye methyl orange using cow and goat milk iron nanoparticles

ABSTRACT Environmental pollution is a global issue, and the contamination of water by dyes is a matter of concern. This work reports an environmentally friendly method for degrading methyl orange dye using iron nanoparticles (INPs) synthesized from pasteurized cow and goat milk and ferric chloride (FeCl3). INPs were synthesized using FeCl3 and milk mixed in a 1:2 (v/v) ratio and subsequently heated at 70 0C. The formation of INPs was monitored by visualizing the color changes. The synthesized NPs were characterized by FTIR, SEM, EDS, TEM, XRD, and XPS. The XRD results showed that INPs were formed and had an amorphous structure. TEM data showed smaller semi-spherical particles with sizes of 8-27 nm, and they were present in an aggregated state. Dye degradation studies were conducted using INP with UV light exposure and H2O2 addition. Both the processes were monitored using UV/Vis scans at different time intervals. The results showed that the degradation of methyl orange was faster in the presence of H2O2 (over 85% efficiency in 60 min) than in the presence of UV light. The current study shows that the INPs formed using milk have the potential to be used as catalysts in azo dye degradation reactions.

Enhanced photocatalytic water splitting over nickel-doped CdS nanocomposites synthesized via one-step controllable irradiation routine at ambient conditions

The work presents an ambient, facile, and controllable radiation-induced method to synthesize nickel-doped CdS (CdS-xNi) nanocomposites. We found that the optimized CdS-2Ni exhibited enhanced photocatalytic hydrogen (H2) evolution activity (∼3.86 mmol/g/h), which was three times that of pristine CdS-γ, and far superior to that of CdS-H (0.04 mmol/g/h) prepared by the conventional hydrothermal method. The analysis of transient photocurrent response, EIS, Mott-Schottky plot, PL, UV–vis, and TEM data, attributed the significant enhancement of photocatalytic activity to the sulfur vacancies and Ni active sites. We showed the ionizing radiation synthesis routine could alter the conduction band (CB) to be more negative and enable a stronger reduction capacity of electron-hole pairs. Furthermore, the doping of Ni induced the increase of sulfur vacancy and lattice distortion, which acted as the electron capture center of proton reduction and suppressed the electron transport, thereby efficiently separating the carriers and prolonging their lifetime. The radiation synthesis technology developed in this study provides a new path for the mild and controllable synthesis of high-performance photocatalysts.