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1.
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
2.
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
3.
PLoS One ; 19(7): e0304373, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38959223

RESUMO

Crystal type is an important physicochemical property of starch. However, it is currently unclear whether changes in crystal type affect other properties of starch. This study discovered that water deficit resulted in an increase in small starch granules and transparency in Pueraria lobata var. thomsonii, while causing a decrease in amylose content and swelling power. Additionally, the crystal type of P. Thomsonii starch changed from CB-type to CA-type under water deficit, without significantly altering the short-range ordered structure and chain length distribution of starch. This transformation in crystal type led to peak splitting in the DSC heat flow curve of starch, alterations in gelatinization behavior, and an increase in resistant starch content. These changes in crystalline structure and physicochemical properties of starch granules are considered as adaptive strategies employed by P. Thomsonii to cope with water deficit.


Assuntos
Amilose , Pueraria , Amido , Água , Pueraria/química , Amido/química , Água/química , Amilose/química , Amilose/análise , Cristalização , Difração de Raios X , Varredura Diferencial de Calorimetria
4.
Methods Enzymol ; 700: 349-383, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38971607

RESUMO

Small-angle X-ray and neutron scattering (SAXS/SANS) techniques excel in unveiling intricate details of the internal structure of lipid membranes under physiologically relevant temperature and buffer conditions, all without the need to resort to bulky labels. By concurrently conducting and analyzing neutron and X-ray data, these methods harness the complete spectrum of contrast and resolution from various components constituting lipid membranes. Despite this, the literature exhibits only a sparse presence of applications compared to other techniques in membrane biophysics. This chapter serves as a primer for conducting joint SAXS/SANS analyses on symmetric and asymmetric large unilamellar vesicles, elucidating fundamental elements of the analysis process. Specifically, we introduce the basics of interactions of X-rays and neutrons with matter that lead to the scattering contrast and a description of membrane structure in terms of scattering length density profiles. These profiles allow fitting of the experimentally observed scattering intensity. We further integrate practical insights, unveiling strategies for successful data acquisition and providing a comprehensive assessment of the technique's advantages and drawbacks. By amalgamating theoretical underpinnings with practical considerations, this chapter aims to dismantle barriers hindering the adoption of joint SAXS/SANS approaches, thereby encouraging an influx of studies in this domain.


Assuntos
Difração de Nêutrons , Espalhamento a Baixo Ângulo , Difração de Raios X , Difração de Nêutrons/métodos , Difração de Raios X/métodos , Lipídeos de Membrana/química , Lipossomas Unilamelares/química , Bicamadas Lipídicas/química
5.
Methods Enzymol ; 700: 49-76, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38971612

RESUMO

High pressure is both an environmental challenge to which deep sea biology has to adapt, and a highly sensitive thermodynamic tool that can be used to trigger structural changes in biological molecules and assemblies. Lipid membranes are amongst the most pressure sensitive biological assemblies and pressure can have a large influence on their structure and properties. In this chapter, we will explore the use of high pressure small angle X-ray diffraction and high pressure microscopy to measure and quantify changes in the lateral structure of lipid membranes under both equilibrium high pressure conditions and in response to pressure jumps.


Assuntos
Pressão Hidrostática , Bicamadas Lipídicas , Difração de Raios X , Difração de Raios X/métodos , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Espalhamento a Baixo Ângulo , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo , Termodinâmica
6.
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
7.
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
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.
AAPS PharmSciTech ; 25(6): 169, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39043992

RESUMO

Motion sickness also known as kinetosis is a condition in which there exists a disagreement between visually perceived movement and the vestibular system's sense of movement. Nausea, vomiting, dizziness, fatigue, and headache are the most common symptoms of motion sickness. This study mainly focuses on the taste masking of Promethazine Hydrochloride (PMZ) by inclusion complexation method, its formulation development in the chewing gum form by using directly compressible gum base HIG® and its quality and performance testing. Different molar ratios (1:1, 1:2, 1:3 and 1:4) of PMZ-cyclodextrin complexes were prepared by using ß-Cyclodextrin (ß-CD) as a taste masking agent. These complexes were evaluated for FTIR, DSC, % Entrapment Efficiency, % drug yield, and taste evaluation by E-Tongue. The optimized ratio was further evaluated by sophisticated analytical techniques such as Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD). A central composite design (CCD) (3 ^2) was utilized to examine the effects of independent variables (amount of gum-X1 and amount of plasticizer-X2) on dependent variables (%CDRY1 and hardness Y2). The prepared gums were evaluated for drug content, organoleptic properties, in-vitro dissolution testing by fabricated disintegration apparatus, texture analysis, etc. The optimization statistics showed that on decreasing the amount of gum, in- vitro drug release increases and hardness decreases. The optimized batch MCG-2 of Promethazine MCG showed 92.34 ± 0.92% of drug release, whereas for marketed formulation (Phenergan®-25 mg) drug release value was 86.19 ± 1.88%. Results provided evidence that PMZ MCGs could be a better alternative to conventional tablet formulations with improved drug release, palatability and texture.


Assuntos
Antieméticos , Goma de Mascar , Prometazina , Paladar , beta-Ciclodextrinas , Prometazina/química , Prometazina/administração & dosagem , beta-Ciclodextrinas/química , Paladar/efeitos dos fármacos , Antieméticos/administração & dosagem , Antieméticos/química , Química Farmacêutica/métodos , Liberação Controlada de Fármacos , Difração de Raios X/métodos , Solubilidade , Composição de Medicamentos/métodos , Humanos , Enjoo devido ao Movimento/prevenção & controle
11.
BMC Oral Health ; 24(1): 824, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033148

RESUMO

BACKGROUND: Excessive inflammation is a major cause of implant failure. The surface morphology, hydrophilicity, and loading of biomaterials are major properties modulating anti-inflammatory macrophage activation. This paper investigates the regulatory effects of modifying the surface of Titanium dioxide nanotubes (TNTs) with graphene oxide (GO) on the polarization of mouse monocyte macrophages (RAW264.7). METHODS: TNT was produced by the anodic oxidation of titanium. GO was subsequently electrodeposited on the TNT to obtain a TNT-GO composite. The samples were characterised through scanning electron microscopy (SEM), Raman spectroscopy, and X-ray diffraction. RAW264.7 cells were separately seeded onto the surface of three groups of samples: pure Ti, TNT, and TNT-GO. Under the condition of lipopolysaccharide stimulation, the influence of the sample surfaces on the gene expression profiles was investigated through RNA sequence analysis. In addition, cell spreading was observed through SEM, cell adhesion and proliferation were analysed using the CCK8 assay, and the expression of inflammation-related factors was investigated by ELISA and cellular immunofluorescence staining. The production of reactive oxygen species (ROS) in the RAW264.7 cells on the surface of the three groups was detected via immunofluorescence staining. RESULTS: The CCK8 results indicated that the adhesion and proliferation of the RAW264.7 cells were reduced on the TNT and TNT-GO surfaces. ELISA results revealed significant differences in the pro-inflammatory factors tumour necrosis factor-α and interleukin-6 secretion among the three groups at 24 h (p < 0.05). The secretion of pro-inflammatory factors significantly reduced and the expression of anti-inflammatory factor IL-10 increased on the TNT and TNT-GO surfaces. The RNA sequencing, ELISA, and cell immunofluorescence staining test results suggested that the inflammatory response of M1 polarization was reduced and the M2 polarization of macrophages was induced on the TNT-GO surface, which may be attributed to the reduction in ROS production. CONCLUSIONS: Under lipopolysaccharide stimulation, the inflammatory response of the RAW264.7 cells was reduced and the M2 polarization of macrophages was promoted on the TNT-GO surface, which may be caused by the reduced ROS production. Consequently, the designed TNT-GO material is promising for implants owing to its excellent inflammation regulation ability.


Assuntos
Grafite , Macrófagos , Nanotubos , Espécies Reativas de Oxigênio , Titânio , Grafite/farmacologia , Animais , Camundongos , Macrófagos/efeitos dos fármacos , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Inflamação , Adesão Celular/efeitos dos fármacos , Propriedades de Superfície , Lipopolissacarídeos , Microscopia Eletrônica de Varredura , Proliferação de Células/efeitos dos fármacos , Análise Espectral Raman , Difração de Raios X , Ativação de Macrófagos/efeitos dos fármacos
12.
Mol Biol Rep ; 51(1): 838, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042226

RESUMO

BACKGROUND: Bioglass materials have gained significant attention in the field of tissue engineering due to their osteoinductive and biocompatible properties that promote bone cell differentiation. In this study, a novel composite scaffold was developed using a sol-gel technique to combine bioglass (BG) 58 S with a poly L-lactic acid (PLLA). METHODS AND RESULTS: The physiochemical properties, morphology, and osteoinductive potential of the scaffolds were investigated by X-ray diffraction analysis, scanning electron microscopy, and Fourier-transform infrared spectroscopy. The results showed that the SiO2-CaO-P2O5 system was successfully synthesized by the sol-gel method. The PLLA scaffolds containing BG was found to be osteoinductive and promoted mineralization, as demonstrated by calcium deposition assay, upregulation of alkaline phosphatase enzyme activity, and Alizarin red staining data. CONCLUSIONS: These in vitro studies suggest that composite scaffolds incorporating hBMSCs are a promising substitute material to be implemented in bone tissue engineering. The PLLA/BG scaffolds promote osteogenesis and support the differentiation of bone cells, such as osteoblasts, due to their osteoinductive properties.


Assuntos
Materiais Biocompatíveis , Diferenciação Celular , Cerâmica , Osteogênese , Poliésteres , Engenharia Tecidual , Alicerces Teciduais , Poliésteres/química , Alicerces Teciduais/química , Cerâmica/química , Cerâmica/farmacologia , Engenharia Tecidual/métodos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Osteogênese/efeitos dos fármacos , Humanos , Diferenciação Celular/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Difração de Raios X , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Fosfatase Alcalina/metabolismo , Microscopia Eletrônica de Varredura
13.
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
14.
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
15.
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
16.
Eur J Pharm Biopharm ; 201: 114380, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38960290

RESUMO

We have used pulsed field gradient (PFG)-NMR diffusion experiments, also known as DOSY, in combination with small angle X-ray scattering measurements to investigate structure and molecular exchange dynamics between pharmaceutical lipid nanoparticles and the bulk phase. Using liposomes and lipoplexes formed after complexation of the liposomes with messenger mRNA as test systems, information on dynamics of encapsulated water molecules, lipids and excipients was obtained. The encapsulated fraction, having a diffusivity similar to that of the liposomes, could be clearly identified and quantified by the NMR diffusion measurements. The unilamellar liposome membranes allowed a fast exchange of water molecules, while sucrose, used as an osmolyte and model solute, showed very slow exchange. Upon interactions with mRNA a topological transition from a vesicular to a lamellar organization took place, where the mRNA was inserted in repeating lipid bilayer stacks. In the lipoplexes, a small fraction of tightly bound water molecules was present, with a diffusivity that was influenced by the additional presence of sucrose. This extended information on dynamic coherencies inside pharmaceutical nanoparticle products, provided by the combined application of SAXS and PFG-NMR diffusion measurements, can be valuable for evaluation of quality and comparability of nanoscaled pharmaceuticals.


Assuntos
Lipossomos , Espectroscopia de Ressonância Magnética , Nanopartículas , RNA Mensageiro , Espalhamento a Baixo Ângulo , Difração de Raios X , Nanopartículas/química , Espectroscopia de Ressonância Magnética/métodos , Difusão , Cinética , Difração de Raios X/métodos , Sacarose/química , Lipídeos/química , Água/química , Excipientes/química , Bicamadas Lipídicas/química
17.
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
18.
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
19.
Microb Pathog ; 193: 106779, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38964486

RESUMO

Dillenia indica is a medicinal tree of the Dilleniaceae and its flower extract was used for the synthesis of silver nanoparticle (AgNPs). The optimal conditions for AgNPs synthesis were as such: 2 mM AgNO3, pH 4.5 and 48-h reaction time. The characteristic band of AgNPs was observed at the wavelength of 435 nm by UV-visible spectroscopic study. Fourier-transform infrared (FTIR) analysis depicted the involvement of several functional groups of plant extracts in the synthesis of AgNPs. Nanoparticles were mostly spherical shaped and uniformly distributed, when observation was made by Transmission electron microscopy (TEM). Energy Dispersive X-Ray (EDX) showed absorption peak approximately at 3 keV thus confirmed the presence of silver metal in AgNP. X-ray diffraction (XRD) investigation and selected area electron diffraction (SAED) patterns showed the crystalline nature of the AgNPs. Dynamic light scattering (DLS) analysis exhibited average size of the nanoparticles as 50.17 nm with a polydispersity index (PDI) value of 0.298. The zeta potential of nanoparticles was observed as -24.9 mV. To assess antibacterial activity, both AgNPs alone or its combination with the antibiotic were tried against six pathogenic bacteria. The combination of AgNPs with antibiotic was maximum effective against Shigella boydii (16.07 ± 0.35) and Klebsiella pneumoniae (15.03 ± 0.20). AgNPs alone showed maximum inhibition for both Gram-positive bacteria: methicillin-resistant Staphylococcus aureus (19.97 ± 0.20 mm) and Enterococcus faecium (19.80 ± 0.15 mm). Maximum inhibition of Enterobactor cloacae and Pseudomonas aeruginosa was observed by antibiotic taken alone. Evaluation through 2,2-diphenyl-1-picrylhydrazyl (DPPH) and DNA nicking assays demonstrated the antioxidant capabilities of the nanoparticles.


Assuntos
Antibacterianos , Antioxidantes , Dilleniaceae , Flores , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata , Prata/farmacologia , Prata/química , Antibacterianos/farmacologia , Antibacterianos/química , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antioxidantes/farmacologia , Antioxidantes/química , Flores/química , Dilleniaceae/química , Bactérias/efeitos dos fármacos , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Microscopia Eletrônica de Transmissão , Tamanho da Partícula
20.
Bioresour Technol ; 406: 131065, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38969241

RESUMO

Lithium-sulfur batteries are a promising alternative to lithium-ion batteries as they can potentially offer significantly increased capacities and energy densities. The ever-increasing global battery market demonstrates that there will be an ongoing demand for cost effective battery electrode materials. Materials derived from waste products can simultaneously address two of the greatest challenges of today, i.e., waste management and the requirement to develop sustainable materials. In this study, we detail the carbonisation of gelatin from blue shark and chitin from prawns, both of which are currently considered as waste biproducts of the seafood industry. The chemical and physical properties of the resulting carbons are compared through a correlation of results from structural characterisation techniques, including electron imaging, X-ray diffraction, Raman spectroscopy and nitrogen gas adsorption. We investigated the application of the resulting carbons as sulfur-hosting electrode materials for use in lithium-sulfur batteries. Through comprehensive electrochemical characterisation, we demonstrate that value added porous carbons, derived from marine waste are promising electrode materials for lithium-sulfur batteries. Both samples demonstrated impressive capacity retention when galvanostatically cycled at a rate of C/5 for 500 cycles. This study highlights the importance of looking towards waste products as sustainable feeds for battery material production.


Assuntos
Carbono , Fontes de Energia Elétrica , Eletrodos , Lítio , Enxofre , Resíduos , Lítio/química , Enxofre/química , Carbono/química , Difração de Raios X , Análise Espectral Raman
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