Nanoscale Range Research Articles

Effect of Mg2+-, Sr2+-, and Fe3+-substitution on 85Sr and 60Co adsorption on amorphous calcium phosphates: Adsorption performance, selectivity, and mechanism

Hydroxyapatite Ca10(OH)2(PO4)6 is a well-known efficient adsorbent of dyes, heavy metal ions, and radionuclides. Its adsorption efficacy strongly depends on crystalline/amorphous structure, defectiveness, texture characteristics, and morphology. Herein, we synthesized Mg2+-, Sr2+-, and Fe3+-substituted (5 mol%) amorphous calcium phosphates as an effective 85Sr and 60Co radionuclides adsorbents. The introduction of Mg2+-, Sr2+-, and Fe3+ ions led to the formation of amorphous calcium phosphates with particles size in the nanoscale range of approximately 10–50 nm. The features of the adsorption behavior of amorphous calcium phosphates were determined depending on the variation of the pH of aqueous, NaCl and CaCl2 solutions. Fe3+-substituted samples demonstrated the superior adsorption efficiency to 85Sr (Kd 7.77 ×103 cm3/g) and 60Co (Kd 6.84 ×104 cm3/g) radionuclides at pH of 10.0 and 4.0, respectively. The adsorption performance of obtained adsorbents slowly decreased at 0.1 M NaCl backgrounds and Kd85Sr and 60Co reached 1.67 × 103 and 2.78 × 104 cm3/g for non-substituted calcium phosphate. The dramatic decrease of calcium phosphates adsorbents efficiency to 85Sr (Kd <150 cm3/g) and 60Co (Kd <1.34 ×103 cm3/g) for 0.05 M CaCl2 model solution was established. The adsorption mechanism of dissolution-precipitation (for 85Sr) and chemisorption (for 60Co) was proposed. Fe3+-substituted calcium phosphate showed the competitive affinity and selectivity to 85Sr and 60Co comparing with described inorganic adsorbents and to be considered as prospective adsorbent for wastewater treatment in nuclear industry.

High yield production of chitin nanocrystals via hydrochloric acid vapor pre-treatment

Traditionally, chitin nanocrystals (ChNCs) are extracted from natural chitin suffered from huge chemical consumption and low yields. Herein, we show that ChNCs can be prepared in yields up to 95.5% by a pretreatment process using HCl vapor to assist exfoliation. It is shown that HCl vapor mainly caused disintegration of amorphous chitin, without excessive hydrolysis of the crystalline region. TEM images showed that chitin exposed to HCl vapor for a certain time readily separated into discernable rods with diameters in the nanoscale range. XRD and TGA analysis showed that the crystallinity and thermal stability of ChNCs were comparable to those of the untreated chitin. In addition, ChNCs was applied as efficient stabilizer for oil-in-water (O/W) emulsions.

Nanophytomedicine in Clinical Management: An Introductory Evidence-based Review

Introduction: Herbal medicines are an important ingredient of traditional and alternative medicinal system and thus being used since ancient times. Owing to their characteristic of having lesser side effects and potential therapeutic effect they have drawn attention of pharmaceutical scientists from across the globe. Herbal medicines have now strongly captured a whooping US $62 billion market globally. Herbal medicines have been widely accepted of their potential to treat chronic diseases, low toxicity profile, cheap and wide availability etc. Methods: The Safety and efficacy of herbal drugs have played an important part in their successful commercialization. With the emergence and application of nanotechnology the bioavailability and bioactivity of herbal medicines have improved drastically. Results: Development of nano-phytomedicines by reducing their size to nano scale range, attaching it with polymers and by modifying their surface properties, solubility, permeability, eventually enhances the bioavailability of herbal formulations. Conclusion: Novel formulations like niosomes, liposomes, nanospheres, phytosomes etc. can be exploited in this area. However, novel nano-phytomedicines comes with its own pros and cons. This article extensively reviews herbal nano-medicines with its reported success and failures.

Comparative investigation of physicochemical properties of cadmium oxide nanoparticles

CdO nanoparticles (CdO NPs) were synthesized utilizing urea-assisted auto-combustion (AC) and microwave combustion (MC) methods. The structural, thermal, optical, morphological, and compositional analysis of the prepared samples were investigated after they were heat treated at 350 °C. The impact of heat treatment and the method of synthesis on their physicochemical properties were investigated. XRD was used to determine the phase, crystallite size, and lattice constant of CdO NPs. The modification of the phase and crystallite size of CdO NPs indicates the impact of the heat treatment and synthesis process. The annealing process raises the crystallite size from 28 nm to 45 nm for the auto combustion approach and from 24 nm to 40 nm for the microwave combustion method. Under heat treatment, the energy band gaps of CdO NPs from auto combustion method and microwave combustion method samples were determined to be 2.09 eV and 1.65 eV, respectively. The surface morphology of CdO NPs was documented by SEM, indicating that the particle's morphology was modified by the synthesis procedure. The nanoscale range of the particles is confirmed by TEM micrographs of annealed CdO NPs, which is closely matched with the crystallite size derived from XRD. TG-DTA was used to examine the thermal characteristics of annealed CdO NPs.

Poly-L-Lysine-Lactobionic Acid-Capped Selenium Nanoparticles for Liver-Targeted Gene Delivery.

Liver cancer is currently regarded as the second leading cause of cancer-related mortality globally and is the sixth most diagnosed malignancy. Selenium nanoparticles (SeNPs) have attracted favorable attention as nanocarriers for gene therapy, as they possess beneficial antioxidant and anticancer properties. This study aimed to design, functionalize and characterize SeNPs to efficiently bind, protect and deliver pCMV–Luc DNA to hepatocellular carcinoma (HepG2) cells. The SeNPs were synthesized by ascorbic acid reduction and functionalized with poly-L-lysine (PLL) to stabilize and confer positive charges to the nanoparticles. The SeNPs were further decorated with lactobionic acid (LA) to target the asialoglycoprotein receptors abundantly expressed on the surface of the hepatocytes. All SeNPs were spherical, in the nanoscale range (<130 nm) and were capable of successfully binding, compacting and protecting the pDNA against nuclease degradation. The functionalized SeNP nanocomplexes exhibited minimal cytotoxicity (<30%) with enhanced transfection efficiency in the cell lines tested. Furthermore, the targeted SeNP (LA–PLL–SeNP) nanocomplex showed significant (* p < 0.05, ** p < 0.01, **** p < 0.0001) transgene expression in the HepG2 cells compared to the receptor-negative embryonic kidney (HEK293) cells, confirming receptor-mediated endocytosis. Overall, these functionalized SeNPs exhibit favorable features of suitable gene nanocarriers for the treatment of liver cancer.

Nanoscale Metal-Organic Frameworks and Their Nanomedicine Applications.

Abundant connectivity among organic ligands and inorganic metal ions makes the physical and chemical characters of metal-organic frameworks (MOFs) could be precisely devised and modulated for specific applications. Especially nanoscale MOFs (NMOFs), a unique family of hybrid nanomaterials, with merits of holding the nature as the mainstay MOFs and demonstrating particle size in nanoscale range which enable them prospect platform in clinic. Adjustability of composition and structure allows NMOFs with different constituents, shapes, and characteristics. Oriented frameworks and highly porous provide enough space for packing therapeutic cargoes and various imaging agents efficiently. Moreover, the relatively labile metal-ligand bonds make NMOFs biodegradable in nature. So far, as a significant class of biomedically relevant nanomaterials, NMOFs have been explored as drug carriers, therapeutic preparation, and biosensing and imaging preparation owing to their high porosity, multifunctionality, and biocompatibility. This review provides up-to-date developments of NMOFs in biomedical applications with emphasis on size control, synthetic approaches, and surfaces functionalization as well as stability, degradation, and toxicity. The outlooks and several crucial issues of this area are also discussed, with the expectation that it may help arouse widespread attention on exploring NMOFs in potential clinical applications.

METHODOLOGY OF «GREEN» CHEMISTRY IN THE SYNTHESIS OF SUBSTITUTED 2-AMINOPYRANES (PYRIDINE) -3-CARBONITRILE

Numerous studies in the chemistry of heterocyclic compounds today are devoted to solving environmental and economic problems (environmental pollution, irrational use of natural re-sources, etc.). This mini-review summarizes and analyzes the literature data of the last 10 years (2011-2021) on the «green» synthesis of structurally similar 2-aminopyrans (pyridine) -3-carboni-triles (polysubstituted, annelated with different types of articulation of rings, spirocyclic) contain-ing in the heteroring, substituent groups (functional analogs), identical in nature (CN, NH2) and position (at C2 -C3), are similar in production methods, formation routes. The main «green» ap-proach to the synthesis of 2-aminopyran (pyridine)-3-carbonitriles is multicomponent condensa-tion during thermal, ultrasonic, microwave activation, and electrolysis. Reagents in the synthesis of 2-aminopyran-3-carbonitriles are malononitrile, (di) carbonyl compounds (aromatic, alicyclic, aliphatic), phenols, hydroxynaphthols, in the case of 2-aminopyridine-3-carbonitriles -malonodi-nitrile, carbonyl compounds, aminating agents (ammonium acetate, aromatic and heterocyclic amines). Numerous studies devoted to the search for catalysts that can replace toxic catalysts (ali-phatic, heterocyclic amines), which are used repeatedly with the same effectiveness. Promising cat-alysts that meet these requirements have been found -nano-, nanomagnetic, organic, solid hetero-geneous catalysts (based on silicon oxide, titanium oxide, graphene). Much attention is paid to the selection of environmentally friendly solvents, available, cheap (water, ethanol), the use of ionic liquids. Electrochemical synthesis is recognized as «green» because toxic catalysts are replaced by electric current. A series of electrosynthesis reactions of annelated, spiro-fused, polyheteroatomi-cheterosystems obtained in the nanoscale range is presented. A large number of publications over the past decade have shown that the methodology of «green» chemistry provides a low-step, effi-cient, low-waste pathway for the synthesis of substituted 2-aminopyran (pyridine) -3-carbonitriles, which corresponds to the PASE (Pot-Atom-Step-Econiomic) principle. It should be noted that this path is not devoid of disadvantages, such as the use of expensive catalysts and complex hardware design. From a huge number of publications over the last decade on the synthesis of 2-aminopyran (pyridine) -3-carbonitriles, only those concerning the use of the methodology of «green» chemistry, the most significant and informative (21 publications) were selected.

Fast-Charging Anode Materials and Novel Nanocomposite Design of Rice Husk-Derived SiO2 and Sn Nanoparticles Self-Assembled on TiO2(B) Nanorods for Lithium-Ion Storage Applications.

A novel microstructure of anode materials for lithium-ion batteries with ternary components, comprising tin (Sn), rice husk-derived silica (SiO2), and bronze-titanium dioxide (TiO2(B)), has been developed. The goal of this research is to utilize the nanocomposite design of rice husk-derived SiO2 and Sn nanoparticles self-assembled on TiO2(B) nanorods, Sn–SiO2@TiO2(B), through simple chemical route methods. Following that, the microstructure and electrochemical performance of as-prepared products were investigated. The major patterns of the X-ray diffraction technique can be precisely indexed as monoclinic TiO2(B). The patterns of SiO2 and Sn were found to be low in intensity since the particles were amorphous and in the nanoscale range, respectively. Small spherical particles, Sn and SiO2, attached to TiO2(B) nanorods were discovered. Therefore, the influence mechanism of Sn–SiO2@TiO2(B) fabrication was proposed. The Sn–SiO2@TiO2(B) anode material performed exceptionally well in terms of electrochemical and battery performance. The as-prepared electrode demonstrated outstanding stability over 500 cycles, with a high discharge capacity of ∼150 mA h g–1 at a fast-charging current of 5000 mA g–1 and a low internal resistance of around 250.0 Ω. The synthesized Sn–SiO2@TiO2(B) nanocomposites have a distinct structure, the potential for fast charging, safety in use, and good stability, indicating their use as promising and effective anode materials in better power batteries for the next-generation applications.

Synthesis and Evaluation of High Functionality and Quality Cell-penetrating Peptide Conjugated Lipid for Octaarginine Modified PEGylated Liposomes In U251 and U87 Glioma Cells

The use of peptide ligand modified PEGylated liposomes has been widely investigated for tumor targeting. Peptides are mainly inserted in the liposomal lipid bilayer using PEG2K-lipid spacer (Peptide-PEG2K-DSPE). However, a lower cellular uptake from longer nonlinear PEG2K spacer was reported, we here synthesized a high functionality and quality (HFQ) lipid with a short, linear serine-glycine repeated peptide [(SG)5] spacer. The objective of the current study is to develop novel octaarginine (R8) peptide-HFQ lipid grafted PEGylated liposomes for glioma cells targeting. In vitro liposomes characterization showed that the mean particle size of all liposomal formulations was in the nano-scale range < 120 nm, with a small PDI value (i.e. ∼0.2) and had a spherical shape under Transmission Electron Microscope, indicating a homogenous particle size distribution. The flow cytometry in vitro cellular association data with U251 MG and U87 cells revealed that 1.5% R8-(SG)5-lipid-PEGylated liposomes exhibited significantly higher cellular association of ∼15.87 and 7.59-fold than the conventional R8-PEG2K-lipid-PEGylated liposomes (10.4 and 6.19-fold), respectively, relative to the unmodified PEGylated liposomes. Moreover, intracellular distribution studies using confocal laser scanning microscopy (CLSM) corroborated the results of the in vitro cell association. The use of ligand-HFQ-lipid liposomes could be a potential alternative to ligand-PEG2K-lipid-modified liposomes as a drug delivery system for tumor targeting.

Synthesis and investigation of structural, morphological, and magnetic properties of the manganese doped cobalt-zinc spinel ferrite

The current work involves the synthesis of MnxCo0.5−xZn0.5Fe2O4 (x = 0.0, 0.1, 0.2, 0.3, and 0.4) by adopting sol-gel auto combustion technique. For all the samples, the single-phase spinel structure with cubic symmetry was assured by the XRD studies. The crystallite size lies in the nanoscale range of 35.4–43.6 nm as estimated by utilizing Debye-Scherrer formula. FTIR spectroscopy affirms the formation of spinel structure due to the appearance of characteristic vibrational bands near 400 and 600 cm−1 which corresponds to the octahedral and tetrahedral sites respectively. FESEM micrographs reveal the presence of non-uniform grain growth which was agglomerated, inhomogenous in size and shape, and having porous morphology. VSM study exhibits soft ferromagnetic nature due to the low coercivity value. There is a decrement in the saturation magnetization with increasing Mn2+ concentration which is due to the decrease in the crystallite size and non-magnetic nature of the Mn2+.

Effect of zinc oxide on wollastonite: Structural, optical, and mechanical properties

Partial substitution of ZnO for CaO in the wollastonite formula was performed via wet precipitation. The effects of ZnO/CaO replacement on the structure, porosity, morphology, optical, and mechanical properties of the CaO–SiO2 ceramic were examined. Structural results and Fourier transform infrared (FTIR) spectra indicated the existence of mixed phases of wollastonite with hardystonite and willemite with hadystonite composites, depending on the ZnO content. The calculated crystallite size confirmed that the formed composites were in the nanoscale range. The FTIR results verified the mixed phases of the prepared samples. The optical band gap energy (Eg) values of 3.3 and 4.56 eV referred to the willemite phase in samples with high ZnO content. Addition of ZnO increased the bulk density and decreased the porosity of the wollastonite. The reduced porosity controlled the mechanical behavior of the prepared composites. The maximum stress (σu) increased from ∼4.10 to ∼26.68 N/mm2 as the porosity decreased from 52.20% to 40.17% for a ZnO content increased from 0% to 50%. The fracture load increased with the ZnO content. The degradability of samples revealed that the higher the ratio of ZnO to the nominal wollastonite, the more influential it was on the degree of weight loss % and the variation in the pH value. The bioactivity test estimated that all samples surface exposed development of a newly formed apatite layer, consequently evidencing the bioactivity of the prepared ceramic composites. Therefore, such substitution can be used in vital applications.

Clustering of Stearic Acids in Model Phospholipid Membranes Revealed by Double Electron-Electron Resonance.

Free fatty acids play various important roles in biological membranes. Double electron-electron resonance spectroscopy (DEER, also known as PELDOR) of spin-labeled biomolecules is capable of studying magnetic dipole-dipole (d-d) interactions between spin labels at the nanoscale range of distances. Here, DEER is applied to study intermolecular d-d interactions between doxyl-spin-labeled stearic acids (DSA) in gel-phase phospholipid bilayers composed either of an equimolecular mixture of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-sn-glycero-3-phosphocholine or of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine. DEER data obtained for different DSA concentrations showed that DSA molecules at their concentration in the bilayer χ larger than 0.5 mol % are assembled into lateral lipid-mediated clusters, with a characteristic intermolecular distance of 2 nm. Some evidences were obtained indicating that clusters may consist of "subclusters", alternatively appearing in two opposite leaflets. Conventional electron paramagnetic resonance (EPR) spectra for the gel-phase bilayers showed that for χ larger than 2 mol % the molecules in the clusters stick together, forming oligomers. Room-temperature EPR spectra for the liquid-crystalline phase were found to change noticeably for χ larger than 0.5 mol %, which may indicate the clustering in a liquid-crystalline phase similar to that observed by DEER in the gel phase.

Hydrogen storage behavior of Mg/Ni layered nanostructured composite materials produced by accumulative fold-forging

An advanced and newly developed severe plastic deformation (SPD) method called accumulative fold-forging (AFF) was applied to produce layered nanostructured MgNi alloys exhibiting superior hydrogen storage capacity. Microstructural developments and storage properties were characterized in depth to correlate the structure and performance of this advanced material. The enhanced hydrogen storage performance of the magnesium-based layered composite material was investigated in comparison to the pristine state by conducting hydrogenation and dehydrogenation testing. It was also shown that the hydrogen uptake and release characteristics can be controlled by adjusting the layered structure or the Mg: Ni stoichiometry ratio. Refining the grain structure of the magnesium alloy down to the nano-scale range (∼400–900 nm) by applying high cycles AFF consolidation to promote creation of multi-million nanometric interfaces led to superior storage performance with a remarkable hydrogen absorption capacity of up to ∼1.425 wt%. X-ray diffraction (XRD) analysis of the hydrogenated products revealed the formation of MgH2 that indicates the dominance of the magnesium matrix for controlling the hydrogen storage behavior of the layered Mg/Ni composite material. Finally, the relationship between the directional hydrogen storage behavior and the induced structural features upon AFF treatment were also established using quantitative characterization and analytical tools.

Single-Phase Formation of Rh2 O3 Nanoparticles on h-BN Support for Highly Controlled Methane Partial Oxidation to Syngas.

Single-phase formation of active metal oxides on supports has been vigorously pursued in many catalytic applications to suppress undesired reactions and to determine direct structure-property relationships. However, this is difficult to achieve in nanoscale range because the effect of non-uniform metal-support interfaces becomes dominant in the overall catalyst growth, leading to the nucleation of various metastable oxides. Herein, we develop a supported single-phase corundum-Rh2 O3 (I) nanocatalyst by utilizing controlled interaction between metal oxide and h-BN support. Atomic-resolution electron microscopy and first-principle calculation reveal that single-phase formation occurs via uniform and preferential attachment of Rh2 O3 (I) (110) seed planes on well-defined h-BN surface after decomposition of rhodium precursor. By utilizing the Rh/h-BN catalyst in methane partial oxidation, syngas is successfully produced solely following the direct route with keeping a H2 /CO ratio of 2, which makes it ideal for most downstream chemical processes.

Single‐Phase Formation of Rh2O3 Nanoparticles on h‐BN Support for Highly Controlled Methane Partial Oxidation to Syngas

AbstractSingle‐phase formation of active metal oxides on supports has been vigorously pursued in many catalytic applications to suppress undesired reactions and to determine direct structure‐property relationships. However, this is difficult to achieve in nanoscale range because the effect of non‐uniform metal‐support interfaces becomes dominant in the overall catalyst growth, leading to the nucleation of various metastable oxides. Herein, we develop a supported single‐phase corundum‐Rh2O3(I) nanocatalyst by utilizing controlled interaction between metal oxide and h‐BN support. Atomic‐resolution electron microscopy and first‐principle calculation reveal that single‐phase formation occurs via uniform and preferential attachment of Rh2O3(I) (110) seed planes on well‐defined h‐BN surface after decomposition of rhodium precursor. By utilizing the Rh/h‐BN catalyst in methane partial oxidation, syngas is successfully produced solely following the direct route with keeping a H2/CO ratio of 2, which makes it ideal for most downstream chemical processes.

Nanotized kinetin enhances essential oil yield and active constituents of mint via improvement in physiological attributes

Often mint (Mentha arvensis L.) faces unforeseen limitations, resulting in a low yield and quality of essential oil (EO), especially menthol content necessitating the need to explore the potential of modern technology to overcome this predicament. One of such techniques is the use of nanomaterials. The bulk (un-nanotized) form of PGRs (plant growth regulators) has been considered as a potential tool for crop improvement. Utilizing the top-down approach of nanotization, bulk PGR kinetin was ball-milled to the nano-scale range. A pot experiment was conducted on mint applying bulk- and nano-kinetin through foliar application. The concentrations of spray-treatments included 0 (de-ionized water, control), 10, 20, and 30 μM of bulk-as well as nanotized-kinetin. Both forms of kinetin manifested their patterns in the plant. Treatment N2 (20 μM of nanotized-kinetin) excelled in all other treatments for most of the parameters studied. As compared with De-ionized water-spray control, it resulted in the highest improvement in photosynthetic efficiency, Carbonic anhydrase activity, EO content (46.6 %), EO yield (50.8 %), and density as well as the diameter of PGTs (peltate glandular trichomes). Treatment N2, equalled by treatment B2 (20 μM of bulk-kinetin), maximally improved the menthol yield. The highest content and yield of EO, as a result of N2 application, was attributed to its manifestation in terms of the improved photosynthetic machinery, enzyme activity, and vigour (density and diameter) of PGTs. Since treatment N2 increased the most desirable EO-traits, viz. content and yield of EO along with yield of menthol, it might be recommended for successful production of mint.

Spectroscopic characterization of Cu(II), Ni(II), Co(II) complexes, and nano copper complex bearing a new S, O, N-donor chelating ligand. 3D modeling studies, antimicrobial, antitumor, and catalytic activities

A new tridentate hydrazone ligand (HL), its Co(II), Ni(II), Cu(II) complexes (in 1:1, 1:2 molar ratios of metal to ligand), and the mixed-ligand Co(II), Ni(II), Cu(II) complexes of the ligand HL, with 8-HQ in 1:1:1 (M:L:8-HQ) stoichiometry, in addition to a nano Cu(II) complex have been synthesized and characterized using physical, analytical and spectral methods. Octahedral geometry was assigned for all investigated complexes except Cu(II) complex 1 which exhibited square planar arrangement. The TGA results suggested the thermal stability of the current complexes. The XRD data indicated that the particles of Cu(II) complex 2 were situated in nano-scale range. Furthemore, the SEM and TEM images of the nano Cu(II) complex 2 showed spherical and sheet-shaped particles with an average size of 48 nm. The geometries of the metal complexes were optimized with respect to the energy taking the 6-311G(p,d) basis set in Gaussian 09 W program in gaseous phase by DFT. The data obtained revealed that all metal complexes are more reactive than the free ligand HL, and the Cu(II) complex 1 has the highest chemical reactivity. The antimicrobial activity study illustrated enhancement in activity of the free ligand upon complex formation., and the Cu(II) complex 1 may be considered as promising antibacterial agent, and as promising antifungal agent. The results of antitumor activity study revealed an inhibition of HepG-2 cell growth for the ligand HL, with enhancement in activity upon complexation, and the Cu(II) complex 1 exhibited the highest cytotoxic activity. The phenoxazinone synthase activity study indicated the ability of both Cu(II) complexes 1 and 2 to catalyze the oxidative dehydrogenation of 2-aminophenol (OAPH) to 2-aminophenoxazine-3-one (APX) under atmospheric conditions and at room temperature.

Effects of B2O3 substitution for Al2O3 on the crystallization and properties of translucent mica glass-ceramics

The effects of substituting Al2O3 with B2O3 on the structure, crystallization, mechanical properties, thermal properties and optical properties of translucent mica glass-ceramics were thoroughly investigated. The results demonstrated that the addition of 0.5 wt% B2O3 was optimum for glass precipitation, which increases the crystallinity of glass-ceramics and provides good translucency. When the content of B2O3 was greater than 0.5 wt%, both crystallinity and translucency decreased noticeably. The replacement of B2O3 for Al2O3 had no influence on the type of crystal phase and the precipitation of tetrasilicic fluoromica with non-stoichiometric ratio, while it did have an effect on the crystallinity and structure. The crystal sizes of glass-ceramics were in the nanoscale range and the transmittance test results indicated that they exhibit excellent translucency.

Graphene Oxide-Supported Microwell Grids for Preparing Cryo-EM Samples with Controlled Ice Thickness.

Cryogenic-electron microscopy (cryo-EM) is the preferred method to determine 3D structures of proteins and to study diverse material systems that intrinsically have radiation or air sensitivity. Current cryo-EM sample preparation methods provide limited control over the sample quality, which limits the efficiency and high throughput of 3D structure analysis. This is partly because it is difficult to control the thickness of the vitreous ice that embeds specimens, in the range of nanoscale, depending on the size and type of materials of interest. Thus, there is a need for fine regulation of the thickness of vitreous ice to deliver consistent high signal-to-noise ratios for low-contrast biological specimens. Herein, an advanced silicon-chip-based device is developed which has a regular array of micropatterned holes with a graphene oxide (GO) window on freestanding silicon nitride (Six Ny ). Accurately regulated depths of micropatterned holes enable precise control of vitreous ice thickness. Furthermore, GO window with affinity for biomolecules can facilitate concentration of the sample molecules at a higher level. Incorporation of micropatterned chips with a GO window enhances cryo-EM imaging for various nanoscale biological samples including human immunodeficiency viral particles, groEL tetradecamers, apoferritin octahedral, aldolase homotetramer complexes, and tau filaments, as well as inorganic materials.

Bioengineering, characterization, and biological activities of C@CuO@Cu nanocomposite based-mediated the Vicia faba seeds aqueous extract

Vicia faba seeds are a rich source of polyphenolic, and flavonoid compounds that have high antioxidant activity. The aqueous extract of V. faba seeds has been used for the biosynthesis of a nanocomposite (NC) consisting of three different types of nanoparticles that are deposited onto each other as [email protected]2[email protected]. Physicochemical, optical, electrical, and morphological properties of the as-biofabricated [email protected]2[email protected] NC were characterized using different analytical techniques as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Ultraviolet–visible spectroscopy (UV–Vis), Photoluminescence (PL), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray (EDX), Raman, Zeta-potential, and water/moisture content). Results confirmed that V. faba seeds aqueous extract mediated the fabrication of [email protected]2[email protected] NC at high and pure crystalline nature. The nano-formulation had a face center cubic crystallographic system at the nano-scale range using Debye–Scherrer's equation (13.8 nm) in XRD analysis and (20.9 ± 6.2 nm) using TEM analysis. The crystallinity index (1.6) with a large surface area and polycrystalline nature were being investigated. In addition, the biological activity of the synthesized NC was analyzed. [email protected]2[email protected] NC showed high anti-inflammatory activity compared with diclofenac potassium with IC50 = 213.3 μg/mL. Moreover, the nano-formulation had a potent antibacterial activity, particularly against Gram-negative bacteria. Cytotoxicity of the [email protected]2[email protected] NC against MCF7, HCT116, and HepG2 cell lines showed efficient cytotoxic impact with IC50 = 84.8, 116.1, and 120.5 μg/mL, respectively. So, the nanocomposite [email protected]2[email protected] may provide a promising platform for the effective treatment of different types of cancer.