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1.
Methods Enzymol ; 700: 235-273, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38971602

RESUMO

Hierarchic self-assembly is the main mechanism used to create diverse structures using soft materials. This is a case for both synthetic materials and biomolecular systems, as exemplified by the non-covalent organization of lipids into membranes. In nature, lipids often assemble into single bilayers, but other nanostructures are encountered, such as bilayer stacks and tubular and vesicular aggregates. Synthetic block copolymers can be engineered to recapitulate many of the structures, forms, and functions of lipid systems. When block copolymers are amphiphilic, they can be inserted or co-assembled into hybrid membranes that exhibit synergistic structural, permeability, and mechanical properties. One example is the emergence of lateral phase separation akin to the raft formation in biomembranes. When higher-order structures, such as hybrid membranes, are formed, this lateral phase separation can be correlated across membranes in the stack. This chapter outlines a set of important methods, such as X-ray Scattering, Atomic Force Microscopy, and Cryo-Electron Microscopy, that are relevant to characterizing and evaluating lateral and correlated phase separation in hybrid membranes at the nano and mesoscales. Understanding the phase behavior of polymer-lipid hybrid materials could lead to innovative advancements in biomimetic membrane separation systems.


Assuntos
Microscopia Crioeletrônica , Bicamadas Lipídicas , Microscopia de Força Atômica , Polímeros , Microscopia Crioeletrônica/métodos , Polímeros/química , Bicamadas Lipídicas/química , Microscopia de Força Atômica/métodos , Difração de Raios X/métodos , Separação de Fases
2.
Sci Rep ; 14(1): 16424, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013935

RESUMO

Lately, children's daily consumption of some products, such as cereals and candies, has been rising, which provides a compelling rationale for determining any metallic substances that may be present. Monitoring the concentration of certain metals, like nickel, in these products is necessary due to medical issues in humans when consumed regularly. So, in this work, a novel and highly selective carbon paste as a Ni(II) ion-selective sensor was prepared and investigated using ceramic magnesium aluminum spinel nanoparticles as the ionophore and tritolyl phosphate (TOCP) as a plasticizer. A modified co-precipitation method was used to synthesize the spinel nanoparticles. X-ray diffraction, scanning electron microscope with EDAX, transmission electron microscope, and BET surface area were used to determine the phase composition, microstructure, pores size, particle size, and surface area of the synthesized nanoparticles. The spinel nanoparticle was found to have a nano crystallite size with a cubic crystal system, a particle size ranging from 17.2 to 51.52 nm, mesoporous nature (average pore size = 8.72 nm), and a large surface area (61.75 m2/g). The composition ratio of graphite carbon as a base: TOCP as binder: spinal as ionophore was 67.3:30.0:2.7 (wt%) based on potentiometric detections over concentrations from 5.0 × 10-8 to 1.0 × 10-2 mol L-1 with LOD of 5.0 × 10-8 mol L-1. A measurement of 29.22 ± 0.12 mV decade-1 over pH 2.0-7.0 was made for the Nernstian slope. This sensor demonstrated good repeatability over nine weeks and a rapid response of 8 s. A good selectivity was shown for Ni(II) ions across many interferents, tri-, di-, and monovalent cations. The Ni(II) content in spiked real samples, including cocaine, sweets, coca, chocolate, carbonated drinks, cereals, and packages, were measured. The results obtained indicated no significant difference between the proposed potentiometric method and the officially reported ICP method according to the F- and t-test data. In addition to utilizing ANOVA statistical analysis, validation procedures have been implemented, and the results exceed the ICP-MS methodology.


Assuntos
Níquel , Níquel/análise , Níquel/química , Humanos , Criança , Óxido de Magnésio/química , Técnicas Eletroquímicas/métodos , Óxido de Alumínio/química , Nanopartículas/química , Magnésio/química , Magnésio/análise , Íons/análise , Difração de Raios X , Ionóforos/química
3.
PLoS One ; 19(7): e0305060, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39012850

RESUMO

In addressing issues related to electromagnetic interference, the demand for ferrite materials with exceptional magnetic and dielectric properties has escalated recently. In this research, sol-gel auto combustion technique prepared Nickel zinc ferrites substituted with cerium, denoted as Ni0.5Zn0.5Ce0.02Fe1.98O4.X-ray diffraction (XRD), Vibrating Sample Magnetometer (VSM), and Field Emissions Scanning Electron Microscope (FESEM) were used to investigate the structure, magnetic properties, and morphology of Cerium doped NiZn Nano ferrites, respectively. The magnetic and dielectric properties of the sample was examined within a frequency range of 2.5-5.5 GHz. Sample exhibits low permittivity (2.2), high permeability (1.4), low dielectric (0.35) and magnetic loss tangent (-0.5) and highest saturation magnetization measuring 30.28 emu/g. A Novel Double-band, 4x4 MIMO window grill-modeled antennas operating on 3.5 GHz and 4.8 GHz frequency bands for 5G smartphones is designed using the CST microwave studio suite. The performance of window grilled 4x4 MIMO antenna model with Cerium doped NiZn nano ferrites as substrate, is investigated and found the return loss of -35 and -32 dB, with the bandwidth of 200MHz, gain (1.89 & 4.38dBi), envelope correlation coefficient (0.00185), channel capacity loss (0.2bps/Hz), and interterminal isolation of (22& 19dB).The results show that the antenna size is reduced with improved bandwidth, higher isolation and better diversity gain performance using Cerium doped NiZn nano ferrite substrate compared to conventional dielectric substrates.


Assuntos
Cério , Compostos Férricos , Níquel , Zinco , Cério/química , Compostos Férricos/química , Níquel/química , Zinco/química , Difração de Raios X , Micro-Ondas
4.
AAPS PharmSciTech ; 25(6): 152, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38954218

RESUMO

Bedaquiline (BQ) solid lipid nanoparticles (SLNs), which have previously been formulated for parenteral administration, have a risk of patient non-compliance in treating tuberculosis. This research presents a strategy to develop BQ SLNs for oral delivery to improve patient adherence, The upper and lower levels for the formulation excipients were generated from screening experiments. Using 4 input factors (BQ, lecithin, Tween 80, and PEG), a full factorial design from 3 × 2x2 × 2 experiments was randomly arranged to investigate 3 response variables: Particle size distribution (PSD), polydispersity index (PdI), and zeta potential (ZP). High shear homogenization was used to mix the solvent and aqueous phases, with 15% sucrose as a cryoprotectant. The response variables were assessed using a zeta sizer while TEM micrographs confirmed the PSD data. Solid-state assessments were conducted using powdered X-ray diffraction and scanning electron microscopy (SEM) imaging. A comparative invitro assessment was used to determine drug release from an equivalent dose of BQ free base powder and BQ-SLN, both packed in hard gelatin capsules. The sonicated formulations obtained significant effects for PSD, PdI, and ZP. The p-values (0.0001 for PdI, 0.0091 for PSD) for BQ as an independent variable in the sonicated formulation were notably higher than those in the unsonicated formulation (0.1336 for PdI, 0.0117 for PSD). The SEM images were between 100 - 400 nm and delineated nanocrystals of BQ embedded in the lipid matrix. The SLN formulation provides higher drug levels over the drug's free base; a similarity factor (f2 = 18.3) was estimated from the dissolution profiles.


Assuntos
Química Farmacêutica , Diarilquinolinas , Lipídeos , Nanopartículas , Tamanho da Partícula , Diarilquinolinas/química , Diarilquinolinas/administração & dosagem , Nanopartículas/química , Lipídeos/química , Química Farmacêutica/métodos , Excipientes/química , Liberação Controlada de Fármacos , Antituberculosos/administração & dosagem , Antituberculosos/química , Composição de Medicamentos/métodos , Difração de Raios X/métodos , Microscopia Eletrônica de Varredura/métodos , Portadores de Fármacos/química , Administração Oral , Lipossomos
5.
Environ Geochem Health ; 46(8): 265, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954233

RESUMO

Shaanxi Province is located in the most important molybdenum ore district in the world, but a lot of molybdenum tailings have been released, polluting the environment and wasting resources seriously. Taking eleven tailing samples collected at the main molybdenum tailings ponds in Shaanxi Province as the research object, the physical, chemical, and mineralogical characteristics were studied through scanning electron microscope, X-ray fluorescence, X-ray diffraction, inductively coupled plasma mass spectrometer, and others. The ecological risk and utilization potential of molybdenum tailings were investigated through leaching test, geo-accumulation index, potential ecological risk assessment, and other methods. The results demonstrated that the main chemical and mineralogical composition of various molybdenum tailings in Shaanxi Province is similar, and the predominant mineral composition is muscovite, quartz, microcline, and calcite. The potential ecological risk of heavy metals in six molybdenum tailings is high, while Pb and Cd are the main pollution risk elements. Molybdenum tailings contain considerable amounts of critical minerals with huge potential economic value, and molybdenum tailings with high environmental hazards could be converted into a possible source for critical minerals by recovering the critical minerals and repurposing the secondary tailings as an additive or cement substitute. This study provides an innovative idea for the pollution treatment of molybdenum tailings and indicates the prospect of molybdenum tailings as a secondary source for critical minerals.


Assuntos
Molibdênio , Molibdênio/análise , China , Monitoramento Ambiental , Medição de Risco , Mineração , Espectrometria por Raios X , Metais Pesados/análise , Difração de Raios X , Microscopia Eletrônica de Varredura , Poluentes do Solo/análise
6.
AAPS PharmSciTech ; 25(6): 154, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961012

RESUMO

Berberine is used in the treatment of metabolic syndrome and its low solubility and very poor oral bioavailability of berberine was one of the primary hurdles for its market approval. This study aimed to improve the solubility and bioavailability of berberine by preparing pellet formulations containing drug-excipient complex (obtained by solid dispersion). Berberine-excipient solid dispersion complexes were obtained with different ratios by the solvent evaporation method. The maximum saturation solubility test was performed as a key factor for choosing the optimal complex for the drug-excipient. The properties of these complexes were investigated by FTIR, DSC, XRD and dissolution tests. The obtained pellets were evaluated and compared in terms of pelletization efficiency, particle size, mechanical strength, sphericity and drug release profile in simulated media of gastric and intestine. Solid-state analysis showed complex formation between the drug and excipients used in solid dispersion. The optimal berberine-phospholipid complex showed a 2-fold increase and the optimal berberine-gelucire and berberine-citric acid complexes showed more than a 3-fold increase in the solubility of berberine compared to pure berberine powder. The evaluation of pellets from each of the optimal complexes showed that the rate and amount of drug released from all pellet formulations in the simulated gastric medium were significantly lower than in the intestine medium. The results of this study showed that the use of berberine-citric acid or berberine-gelucire complex could be considered a promising technique to increase the saturation solubility and improve the release characteristics of berberine from the pellet formulation.


Assuntos
Berberina , Química Farmacêutica , Composição de Medicamentos , Liberação Controlada de Fármacos , Excipientes , Tamanho da Partícula , Solubilidade , Berberina/química , Berberina/administração & dosagem , Berberina/farmacocinética , Excipientes/química , Composição de Medicamentos/métodos , Química Farmacêutica/métodos , Disponibilidade Biológica , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Pós/química , Difração de Raios X/métodos , Varredura Diferencial de Calorimetria/métodos
7.
Biomed Mater ; 19(5)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38955335

RESUMO

This study aimed to develop and optimize karanjin-loaded ethosomal nanogel formulation and evaluate its efficacy in alleviating symptoms of psoriasis in an animal model induced by imiquimod. These karanjin-loaded ethosomal nanogel, were formulated to enhance drug penetration into the skin and its epidermal retention. Karanjin was taken to formulate ethosomes due to its potential ani-psoriatic activity. Ethosomes were formulated using the cold method using 32full factorial designs to optimize the formulation components. 9 batches were prepared using two independent variablesX1: concentration of ethanol andX2: concentration of phospholipid whereas vesicle size (Y1) and percentage entrapment efficiency (Y2) were selected as dependent variables. All the dependent variables were found to be statistically significant. The optimized ethosomal suspension (B3) exhibited a vesicle size of 334 ± 2.89 nm with an entrapment efficiency of 94.88 ± 1.24% and showed good stability. The morphology of vesicles appeared spherical with smooth surfaces through transmission electron microscopy analysis. X-ray diffraction analysis confirmed that the drug existed in an amorphous state within the ethosomal formulation. The optimized ethosome was incorporated into carbopol 934 to develop nanogel for easy application on the skin. The nanogel underwent characterization for various parameters including spreadability, viscosity, pH, extrudability, and percentage drug content. The ethosomal formulation remarkably enhanced the skin permeation of karanjin and increased epidermal retention of the drug in psoriatic skin compared to marketed preparation and pure drug. A skin retention study showed that ethosomal nanogel formulation has 48.33% epidermal retention in 6 h.In vivo,the anti-psoriatic activity of karanjin ethosomal nanogel demonstrated significant improvement in psoriasis, indicated by a gradual decrease in skin thickness and scaling as reflected in the Psoriasis Severity Index grading. Therefore, the prepared ethosomal nanogel is a potential vehicle for improved topical delivery of karanjin for better treatment of psoriasis.


Assuntos
Nanogéis , Psoríase , Absorção Cutânea , Psoríase/tratamento farmacológico , Psoríase/patologia , Animais , Nanogéis/química , Lecitinas/química , Pele/metabolismo , Pele/patologia , Tamanho da Partícula , Lipossomos/química , Polietilenoglicóis/química , Glycine max/química , Ratos , Masculino , Imiquimode/química , Portadores de Fármacos/química , Polietilenoimina/química , Difração de Raios X , Etanol/química , Acrilatos
8.
J Environ Manage ; 365: 121685, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38963964

RESUMO

Ternary alkali-activated binder was prepared by blast furnace slag (GGBS), recycled powder (RP) and waste glass powder (WGP) using simplex centroid design method. By measuring the fluidity, setting time, drying shrinkage and mechanical property of specimen, the complementary effect of GGBS, RP and WGP was discussed. The reaction mechanism and microstructure were explored by X-ray diffraction and scanning electron microscopy. The results reveal that the addition of RP could significantly reduce the fluidity and setting time of paste, while WGP can obviously improve the rheological property and play a retarding role. The workability of paste can be effectively regulated by mixing RP and WGP together. Whether added alone or in combination, RP and WGP can effectively improve the shrinkage performance. In the ternary system, GGBS can be rapidly activated and form a skeleton structure. The fine RP particles can play a good role in filling the structure, and the pozzolanic reaction of WGP gradually occurs, which makes the microstructure more compact. The incorporation of GGBS, RP and WGP can promote the growth of hydration products, improve the density of microstructure, and form a certain complementary effect.


Assuntos
Álcalis , Vidro , Pós , Reciclagem , Vidro/química , Álcalis/química , Difração de Raios X , Microscopia Eletrônica de Varredura
9.
AAPS PharmSciTech ; 25(6): 164, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-38997569

RESUMO

This study employed a Quality by Design (QbD) approach to spray dry amorphousclotrimazole nanosuspension (CLT-NS) consisting of Soluplus® and microcrystallinecellulose. Using the Box-Behnken Design, a systematic evaluation was conducted toanalyze the impact of inlet temperature, % aspiration, and feed rate on the criticalquality attributes (CQAs) of the clotrimazole spray-dried nanosuspension (CLT-SDNS). In this study, regression analysis and ANOVA were employed to detect significantfactors and interactions, enabling the development of a predictive model for the spraydrying process. Following optimization, the CLT-SD-NS underwent analysis using Xraypowder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR), Dynamic Scanning Calorimetry (DSC), and in vitro dissolution studies. The resultsshowed significant variables, including inlet temperature, feed rate, and aspiration rate,affecting yield, redispersibility index (RDI), and moisture content of the final product. The models created for critical quality attributes (CQAs) showed statistical significanceat a p-value of 0.05. XRPD and DSC confirmed the amorphous state of CLT in theCLT-SD-NS, and FTIR indicated no interactions between CLT and excipients. In vitrodissolution studies showed improved dissolution rates for the CLT-SD-NS (3.12-foldincrease in DI water and 5.88-fold increase at pH 7.2 dissolution media), attributed torapidly redispersing nanosized amorphous CLT particles. The well-designed studyutilizing the Design of Experiments (DoE) methodology.


Assuntos
Clotrimazol , Nanopartículas , Suspensões , Clotrimazol/química , Clotrimazol/administração & dosagem , Nanopartículas/química , Suspensões/química , Secagem por Atomização , Química Farmacêutica/métodos , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Tamanho da Partícula , Varredura Diferencial de Calorimetria/métodos , Temperatura , Composição de Medicamentos/métodos , Polivinil/química , Difração de Raios X/métodos , Polietilenoglicóis
10.
PLoS One ; 19(7): e0302563, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985774

RESUMO

Research on personal adornments depends on the reliable characterisation of materials to trace provenance and model complex social networks. However, many analytical techniques require the transfer of materials from the museum to the laboratory, involving high insurance costs and limiting the number of items that can be analysed, making the process of empirical data collection a complicated, expensive and time-consuming routine. In this study, we compiled the largest geochemical dataset of Iberian personal adornments (n = 1243 samples) by coupling X-ray fluorescence compositional data with their respective X-ray diffraction mineral labels. This allowed us to develop a machine learning-based framework for the prediction of bead-forming minerals by training and benchmarking 13 of the most widely used supervised algorithms. As a proof of concept, we developed a multiclass model and evaluated its performance on two assemblages from different Portuguese sites with current mineralogical characterisation: Cova das Lapas (n = 15 samples) and Gruta da Marmota (n = 10 samples). Our results showed that decisión-tres based classifiers outperformed other classification logics given the discriminative importance of some chemical elements in determining the mineral phase, which fits particularly well with the decision-making process of this type of model. The comparison of results between the different validation sets and the proof-of-concept has highlighted the risk of using synthetic data to handle imbalance and the main limitation of the framework: its restrictive class system. We conclude that the presented approach can successfully assist in the mineral classification workflow when specific analyses are not available, saving time and allowing a transparent and straightforward assessment of model predictions. Furthermore, we propose a workflow for the interpretation of predictions using the model outputs as compound responses enabling an uncertainty reduction approach currently used by our team. The Python-based framework is packaged in a public repository and includes all the necessary resources for its reusability without the need for any installation.


Assuntos
Minerais , Minerais/análise , Minerais/química , Algoritmos , Portugal , Difração de Raios X , Espectrometria por Raios X/métodos , Humanos , Aprendizado de Máquina , Aprendizado de Máquina Supervisionado
11.
PLoS One ; 19(7): e0303521, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985793

RESUMO

Microbes maneuver strategies to become incessant and biofilms perfectly play a role in scaling up virulence to cause long-lasting infections. The present study was designed to assess the use of an eco-friendly formulation of functionalized silver nanoparticles generated from Mentha longifolia leaf extract (MℓE) for the treatment of biofilm-producing microbes. Nanoparticles synthesized using MℓE as a reducing agent were optimized at different strengths of AgNO3 (1 mM, 2 mM, 3 mM, and 4 mM). Synthesis of M. longifolia silver nanoparticles (MℓAgNPs) was observed spectrophotometrically (450 nm) showing that MℓAgNPs (4 mM) had the highest absorbance. Various techniques e.g., Fourier transforms Infrared spectroscopy (FTIR), Dynamic light scattering (DLS), zeta potential (ZP), X-ray Diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM) were used to characterize MℓAgNPs. In the present study, the Kirby-Bauer method revealed 4mM was the most detrimental conc. of MℓAgNPs with MIC and MBC values of 0.62 µg/mL and 1.25 µg/mL, 0.03 µg/mL and 0.078 µg/mL, and 0.07 µg/mL and 0.15 µg/mL against previously isolated and identified clinical strains of Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Staphylococcus aureus, respectively. Moreover, the MℓAgNP antibiofilm activity was examined via tissue culture plate (TCP) assay that revealed biofilm inhibition of up to 87.09%, 85.6%, 83.11%, and 75.09% against E. coli, P. aeruginosa, K. pneumonia, and S. aureus, respectively. Herbal synthesized silver nanoparticles (MℓAgNPs) tend to have excellent antibacterial and antibiofilm properties and are promising for other biomedical applications involving the extrication of irksome biofilms. For our best knowledge, it is the first study on the use of the green-synthesized silver nanoparticle MℓAgNP as an antibiofilm agent, suggesting that this material has antibiotic, therapeutic, and industrial applications.


Assuntos
Antibacterianos , Biofilmes , Mentha , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata , Staphylococcus aureus , Biofilmes/efeitos dos fármacos , Mentha/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prata/química , Prata/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Folhas de Planta/microbiologia , Escherichia coli/efeitos dos fármacos , Difração de Raios X , Nanoestruturas/química
12.
Molecules ; 29(13)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38999153

RESUMO

BACKGROUND: Ophiocordyceps sinensis has long been recognized as a mysterious and valuable traditional Chinese medicine but there has been little research on quality markers for O. sinensis. PURPOSE: This study looked into the potential of using powder X-ray diffractometry (PXRD) to analyze polysaccharides as a quality marker for O. sinensis. STUDY DESIGN: There were 16 different habitats of O. sinensis collected in Qinghai, Gansu, Sichuan, Yunnan, and Tibet. In addition, five different types of Cordyceps species were collected. The characteristic diffraction peaks of O. sinensis were determined and then matched with the characteristic diffraction peaks of intracellular polysaccharides obtained from O. sinensis to determine the attribution relationship of the characteristic diffraction peaks. METHODS: O. sinensis powder's X-ray diffraction pattern is determined by its composition, microcrystalline crystal structure, intramolecular bonding mechanism, and molecular configuration. After fractionation and alcohol precipitation of crude intracellular polysaccharide, mycelium crude intracellular polysaccharide (MCP) and fruiting body crude intracellular polysaccharide (FCP) were obtained and the fingerprint of O. sinensis was identified by the specific characteristic peaks of the X-ray diffraction pattern from intracellular polysaccharide. RESULTS: The results indicated that the PXRD patterns of different populations of O. sinensis were overlaid well with 18 characteristic diffraction peaks obtained by microcrystalline diffraction. Moreover, the powder diffractograms as a fingerprint provided a practical identification of O. sinensis from other Cordyceps species. In addition, we detected that the powder diffractograms of intracellular polysaccharide MCP and MCP75 could be coupled with the PXRD of O. sinensis. Specifically, 18 characteristic diffraction peaks were identified as coming from MCP and MCP75 according to those interplanar crystal spacing, which matched well with those of PXRD of O. sinensis. CONCLUSIONS: PXRD spectra combined with an updated multivariable discriminant model were found to be an efficient and sensitive method for O. sinensis quality control. According to the findings of this study, PXRD should be further investigated for quality control assessments and plant extract selection trials.


Assuntos
Cordyceps , Polissacarídeos , Difração de Raios X , Cordyceps/química , Polissacarídeos/química , Polissacarídeos/análise , Medicina Tradicional Chinesa , Hypocreales/química
13.
Int J Mol Sci ; 25(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39000062

RESUMO

The present work focuses on the synthesis of a vanadium nitride (VN)/carbon nanocomposite material via the thermal decomposition of vanadyl phthalocyanine (VOPC). The morphology and chemical structure of the synthesized compounds were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoemission spectroscopy (XPS). The successful syntheses of the VOPC and non-metalated phthalocyanine (H2PC) precursors were confirmed using FTIR and XRD. The VN particles present a needle-like morphology in the VN synthesized by the sol-gel method. The morphology of the VN/C composite material exhibited small clusters of VN particles. The XRD analysis of the thermally decomposed VOPC indicated a mixture of amorphous carbon and VN nanoparticles (VN(TD)) with a cubic structure in the space group FM-3M consistent with that of VN. The XPS results confirmed the presence of V(III)-N bonds in the resultant material, indicating the formation of a VN/C nanocomposite. The VN/C nanocomposite synthesized through thermal decomposition exhibited a high carbon content and a cluster-like distribution of VN particles. The VN/C nanocomposite was used as an anode material in LIBs, which delivered a specific capacity of 307 mAh g-1 after 100 cycles and an excellent Coulombic efficiency of 99.8 at the 100th cycle.


Assuntos
Carbono , Nanocompostos , Nanocompostos/química , Carbono/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Indóis/química , Vanádio/química , Compostos de Vanádio/química , Espectroscopia Fotoeletrônica
14.
AAPS J ; 26(4): 83, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009955

RESUMO

Salts of weakly basic drugs can partially dissociate in formulations, to give basic drugs and counter acids. The aim of the present study was to clarify the effect of physicochemical properties on the basic drug-acid-polymer interactions and salt-polymer miscibility, and to explain the influence mechanism at the molecular level. Six maleate salts with different physicochemical properties were selected and PVA was used as the film forming material. The relationship between the physicochemical properties and the miscibility was presented with multiple linear regression analysis. The existence state of salts in formulations were determined by XRD and Raman imaging. The stability of salts was characterized by NMR and XPS. The intermolecular interactions were investigated by FTIR and NMR. The results showed that the salt-PVA miscibility was related to polar surface area of salts and Tg of free bases, which represented hydrogen bond interaction and solubility potential. The basic drug-acid-PVA intermolecular interactions determined the existence state and bonding pattern of the three molecules. Meanwhile, the decrease of the stability after formulation increased the number of free bases in orodispersible films, which in turn affected the miscibility with PVA. The study provided references for the rational design of PVA based orodispersible films.


Assuntos
Álcool de Polivinil , Solubilidade , Álcool de Polivinil/química , Administração Oral , Estabilidade de Medicamentos , Maleatos/química , Química Farmacêutica/métodos , Ligação de Hidrogênio , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
15.
Environ Geochem Health ; 46(9): 327, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012555

RESUMO

The novel bioengineered CuO nanoparticles were successfully synthesized directly using green chemistry, the nontoxic and renewable aqueous extract of waste papaya peel (Carica papaya) as a precursor. The XRD analysis indicated a monoclinic phase of CuO nanoparticles and a size of 20 nm, and the optical absorption analysis showed a peak in the 264 nm range. In TEM, the morphology of the NPs was observed to be almost spherical with a particle size of 15 nm. The CuO nanoparticles showed good efficiency in the degradation of methylene, obtaining up to 50% in 40 min using 6 mg in 60 ml of MB at 10 mg/L. The novel presented in this work derives from using rock minerals, from which we have directly obtained copper salt and copper oxide nanoparticles. This process not only utilizes ecological green chemistry but also offers an economic advantage by directly producing nanoparticles from the mineral instead of purchasing costly pure chemical reagents and employing novel nanomaterials to purify wastewater.


Assuntos
Corantes , Cobre , Nanopartículas Metálicas , Cobre/química , Corantes/química , Nanopartículas Metálicas/química , Poluentes Químicos da Água/química , Catálise , Química Verde/métodos , Carica/química , Mineração , Difração de Raios X , Azul de Metileno/química , Microscopia Eletrônica de Transmissão
16.
Int J Nanomedicine ; 19: 6845-6855, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39005957

RESUMO

Objective: Collagen, a widely used natural biomaterial polymer in skin tissue engineering, can be innovatively processed into nanocollagen through cryogenic milling to potentially enhance skin tissue healing. Although various methods for fabricating nanocollagen have been documented, there is no existing study on the fabrication of nanocollagen via cryogenic milling, specifically employing graphene oxide as separators to prevent agglomeration. Methods: In this study, three research groups were created using cryogenic milling: pure nanocollagen (Pure NC), nanocollagen with 0.005% graphene oxide (NC + 0.005% GO), and nanocollagen with 0.01% graphene oxide (NC+0.01% GO). Characterization analyses included transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, x-ray diffraction (XRD), zeta potential (ZP), and polydispersity index (PDI). Results: TEM and SEM analysis revealed that nanocollagen groups alone exhibited particle sizes of less than 100 nm. FTIR spectroscopic investigations indicated the presence of amide A, B, and I, II, and III (1800 to 800 cm-1) in all nanocollagen study groups, with the characteristic C-O-C stretching suggesting the incorporation of graphene oxide (GO). XRD data exhibited broadening of the major peak as the proportion of GO increased from pure NC to the nanocollagen groups with GO. Zeta potential measurements indicated electrostatic attraction of the samples to negatively charged surfaces, accompanied by sample instability. PDI results depicted size diameters ranging from 800 to 1800 nm, indicating strong polydispersity with multiple size populations. Conclusion: This research demonstrated that collagen can be successfully fabricated into nanoparticles with sizes smaller than 100 nm.


Assuntos
Colágeno , Grafite , Tamanho da Partícula , Grafite/química , Colágeno/química , Espectroscopia de Infravermelho com Transformada de Fourier , Materiais Biocompatíveis/química , Difração de Raios X , Engenharia Tecidual/métodos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
17.
Biomed Mater ; 19(5)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016135

RESUMO

The performance and long-term durability of dental implants hinge on the quality of bone integration and their resistance to bacteria. This research aims to introduce a surface modification strategy for zirconia implants utilizing femtosecond laser ablation techniques, exploring their impact on osteoblast cell behavior and bacterial performance, as well as the integral factors influencing the soft tissue quality surrounding dental implants. Ultrafast lasers were employed to craft nanoscale groove geometries on zirconia surfaces, with thorough analyses conducted using x-ray diffraction, scanning electron microscopy, atomic force microscopy, and water contact angle measurements. The study evaluated the response of human fetal osteoblastic cell lines to textured zirconia ceramics by assessing alkaline phosphatase activity, collagen I, and interleukin 1ßsecretion over a 7 day period. Additionally, the antibacterial behavior of the textured surfaces was investigated usingFusobacterium nucleatum, a common culprit in infections associated with dental implants. Ciprofloxacin (CIP), a widely used antibacterial antibiotic, was loaded onto zirconia ceramic surfaces. The results of this study unveiled a substantial reduction in bacterial adhesion on textured zirconia surfaces. The fine biocompatibility of these surfaces was confirmed through the MTT assay and observations of cell morphology. Moreover, the human fetal osteoblastic cell line exhibited extensive spreading and secreted elevated levels of collagen I and interleukin 1ßin the modified samples. Drug release evaluations demonstrated sustained CIP release through a diffusion mechanism, showcasing excellent antibacterial activity against pathogenic bacteria, includingStreptococcus mutans, Pseudomonas aeruginosa, andEscherichia coli.


Assuntos
Antibacterianos , Cerâmica , Lasers , Osteoblastos , Propriedades de Superfície , Zircônio , Zircônio/química , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Cerâmica/química , Cerâmica/farmacologia , Linhagem Celular , Implantes Dentários/microbiologia , Fusobacterium nucleatum/efeitos dos fármacos , Teste de Materiais , Ciprofloxacina/farmacologia , Ciprofloxacina/química , Interleucina-1beta/metabolismo , Aderência Bacteriana/efeitos dos fármacos , Difração de Raios X , Microscopia Eletrônica de Varredura , Fosfatase Alcalina/metabolismo , Microscopia de Força Atômica , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
18.
Radiat Prot Dosimetry ; 200(11-12): 1178-1182, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016485

RESUMO

Polydimethyl silicone rubber-based polymer composites filled with molybdenum and bismuth were fabricated using simple open mold cast technique. The physical and chemical structure and gamma shielding parameters like attenuation coefficient, half-value layer (HVL) thickness and relaxation length have been investigated for the said novel materials using X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and gamma ray spectrometer. XRD study reveals the crystalline nature of the composites. It is evident from FTIR studies that there is no chemical interaction between the polymer matrix and filler particles. The results of attenuation studies reveal that the linear attenuation coefficient increases with addition of Bi and Mo and is found to be 0.653, 1.341 and 1.017, 1.793 and 0.102, 0.152 cm-1 for 1MMB and 2MMB polymer composites at 80, 356 and 662 keV gamma rays, respectively. The HVL thickness of the materials is found to be 1.06, 0.51 and 0.68, 0.38 and 6.73, 4.532 cm for 1MMB (20Mo + 10Bi phr) and 2MMB (40Mo + 20Bi phr) at these energies, respectively. The mass attenuation coefficient of the novel composites 1MMB and 2MMB is found to be higher than the conventional materials like lead and barite for 356 keV gamma rays. In addition, the material is found to be light weight and flexible enabling to be molded in required forms, thus being a substitute for the material lead that is known to be heavy and toxic by nature.


Assuntos
Bismuto , Molibdênio , Polímeros , Polímeros/química , Molibdênio/química , Molibdênio/efeitos da radiação , Bismuto/química , Raios gama , Radiação Ionizante , Proteção Radiológica/métodos , Proteção Radiológica/instrumentação , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Humanos
19.
Radiat Prot Dosimetry ; 200(11-12): 1173-1177, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016480

RESUMO

The effect of 60Co gamma irradiation on gallium oxide and titanium oxide (Ga2O3-TiO2) nanocomposites are investigated in the present study. The Ga2O3-TiO2 nanocomposite was synthesized by hydrothermal method at 120°C. The precursors for the synthesis consist of gallium nitrate anhydrous and titanium trichloride along with sodium hydroxide to achieve the pH of 9. The synthesized Ga2O3-TiO2 was subjected to 60Co gamma irradiation for different doses such as 25, 50 and 75 kGy. The morphological, optical and microstructural characteristics were studied using scanning electron microscopy, UV-Visible spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy, respectively. The results shows that the gamma irradiation induces significant changes in the Ga2O3-TiO2 microstructure and there is increase in the grain size and bandgap of the nanocomposites.


Assuntos
Radioisótopos de Cobalto , Gálio , Raios gama , Nanocompostos , Titânio , Titânio/química , Nanocompostos/química , Nanocompostos/efeitos da radiação , Radioisótopos de Cobalto/química , Gálio/química , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Microscopia Eletrônica de Varredura
20.
Radiat Prot Dosimetry ; 200(11-12): 1158-1162, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016502

RESUMO

The influence of 60Co gamma radiation on Molybdenum Oxide-Cerium Oxide (MoO3-CeO2) nanocomposite is investigated in the present study. The MoO3-CeO2 nanocomposite was synthesized by conventional hydrothermal route. Ammonium hepta molybdate tetrahydrate [(NH4)6Mo7O24.4H2O] and cerium nitrate [Ce (NO3)3.4H2O] were used as the precursors. The composite was subjected to high energy gamma irradiation for different doses of 50, 100 and 150 kGy using 60Co gamma irradiation chamber. The structural study was carried out using X-ray diffraction, the morphological studies were carried out using scanning electron microscopy and ultraviolet-visible spectroscopy was carried out to study the optical properties before and after irradiation. The crystallite size was found to increase with increasing doses of gamma irradiation. The morphology of the samples shows that the nanoparticles tend to agglomerate with increasing doses of gamma radiation. The energy bandgap of the MoO3-CeO2 nanocomposite was calculated before and after irradiation and found to decrease with increasing doses of irradiation upto 100 kGy and then increases for 150 kGy.


Assuntos
Cério , Radioisótopos de Cobalto , Raios gama , Molibdênio , Nanocompostos , Óxidos , Cério/química , Molibdênio/química , Molibdênio/efeitos da radiação , Nanocompostos/química , Nanocompostos/efeitos da radiação , Radioisótopos de Cobalto/química , Óxidos/química , Difração de Raios X , Microscopia Eletrônica de Varredura
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