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24 pages, 4513 KB  
Article
Anticancer Activity of Paclitaxel-Loaded Mesoporous Silica Nanoparticles in B16F10 Melanoma-Bearing Mice
by Jihoon Lee, Jung Mo Kim, Yeon-Ju Baek, Hyojeung Kang, Min-Koo Choi and Im-Sook Song
Pharmaceutics 2025, 17(8), 1042; https://doi.org/10.3390/pharmaceutics17081042 - 11 Aug 2025
Viewed by 806
Abstract
Background/Objectives: Paclitaxel (PTX) faces clinical limitations in melanoma treatment due to poor solubility, P-glycoprotein (P-gp)-mediated efflux, and systemic toxicity. This study aimed to develop PTX-loaded mesoporous silica nanoparticles (PS), which would be co-administered with curcumin (CUR) and D-α-tocopherol polyethylene glycol 1000 succinate [...] Read more.
Background/Objectives: Paclitaxel (PTX) faces clinical limitations in melanoma treatment due to poor solubility, P-glycoprotein (P-gp)-mediated efflux, and systemic toxicity. This study aimed to develop PTX-loaded mesoporous silica nanoparticles (PS), which would be co-administered with curcumin (CUR) and D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) to enhance intracellular accumulation and improve anti-tumor activity. CUR and TPGS were integrated with PS to inhibit P-gp-mediated PTX-efflux, to enhance the intracellular accumulation of PTX, and to improve anti-tumor activity in B16F10 cells. Methods: The physicochemical properties of PS were analyzed using standard characterization methods. The antitumor activity of PS co-administered with CUR and TPGS was evaluated using two-dimensional (2D) culture and three-dimensional (3D) spheroid assays, and also assessed in B16F10 tumor-bearing mice. The therapeutic mechanism of the PS combination was compared using apoptosis and microtubule disruption through flow cytometry and confocal microscopy. The pharmacokinetics and biodistribution of the PS combination were compared in B16F10 tumor-bearing mice. Results: PS formulations exhibited amorphous transformation with an approximate particle size of 200 nm. PS co-administered with CUR and TPGS reduced the IC50 to 178.7 nM compared with 283.3 nM for free PTX in B16F10 melanoma cells and achieved significant tumor growth inhibition in B16F10 melanoma spheroid culture. The intracellular accumulation of PTX correlated with its therapeutic efficacy. Flow cytometry revealed a significant induction of both early and late apoptosis in cells treated with the PS + CUR + TPGS combination, while confocal imaging confirmed enhanced microtubule disruption. In B16F10 tumor-bearing mice, PS co-administered with CUR and TPGS demonstrated higher and selective distribution of PTX into tumor tissue without affecting systemic exposure of PTX in B16F10-xenografted mice. Conclusions: PS + CUR + TPGS combination enhanced PTX delivery by improving solubility and enhancing distribution to tumor tissue through P-gp inhibition, thereby increasing its therapeutic potential. The combination of CUR and TPGS offers synergistic apoptosis induction and microtubule disruption. Thus, the PS + CUR + TPGS combination represents a promising approach for treating drug-resistant melanomas. Full article
(This article belongs to the Special Issue Targeted Drug Delivery to Improve Cancer Therapy, 2nd Edition)
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27 pages, 4348 KB  
Article
Valorization of Riceberry Broken Rice and Soybean Meal for Optimized Production of Multifunctional Exopolysaccharide by Bacillus tequilensis PS21 with Potent Bioactivities Using Response Surface Methodology
by Thipphiya Karirat, Worachot Saengha, Nantaporn Sutthi, Pheeraya Chottanom, Sirirat Deeseenthum, Nyuk Ling Ma and Vijitra Luang-In
Polymers 2025, 17(15), 2029; https://doi.org/10.3390/polym17152029 - 25 Jul 2025
Viewed by 660
Abstract
This study explores the valorization of agro-industrial by-products—riceberry broken rice (RBR) and soybean meal (SBM)—as cost-effective substrates for enhancing exopolysaccharide (EPS) production by Bacillus tequilensis PS21. Eight Bacillus strains were screened, and B. tequilensis PS21 demonstrated the highest EPS yield (2.54 g/100 mL [...] Read more.
This study explores the valorization of agro-industrial by-products—riceberry broken rice (RBR) and soybean meal (SBM)—as cost-effective substrates for enhancing exopolysaccharide (EPS) production by Bacillus tequilensis PS21. Eight Bacillus strains were screened, and B. tequilensis PS21 demonstrated the highest EPS yield (2.54 g/100 mL DW). The EPS displayed a strong antioxidant capacity with 65.5% DPPH and 80.5% hydroxyl radical scavenging, and a FRAP value of 6.51 mg Fe2+/g DW. Antimicrobial testing showed inhibition zones up to 10.07 mm against Streptococcus agalactiae and 7.83 mm against Staphylococcus aureus. Optimization using central composite design (CCD) and the response surface methodology (RSM) revealed the best production at 5% (w/v) RBR, 3% (w/v) SBM, pH 6.66, and 39.51 °C, yielding 39.82 g/L EPS. This EPS is a moderate-molecular-weight (11,282 Da) homopolysaccharide with glucose monomers. X-ray diffraction (XRD) showed an amorphous pattern, favorable for solubility in biological applications. Thermogravimetric analysis (TGA) demonstrated thermal stability up to ~250 °C, supporting its suitability for high-temperature processing. EPS also exhibited anticancer activity with IC50 values of 226.60 µg/mL (MCF-7) and 224.30 µg/mL (HeLa) at 72 h, reduced colony formation, inhibited cell migration, and demonstrated anti-tyrosinase, anti-collagenase, and anti-elastase effects. This study demonstrates the successful valorization of agro-industrial by-products—RBR and SBM—for the high-yield production of multifunctional EPS with potent antioxidant, antimicrobial, and anticancer properties. The findings highlight the sustainable potential of these low-cost substrates in supporting the development of green and value-added bioproducts, with promising utilizations across the food, pharmaceutical, and cosmetic sectors. Full article
(This article belongs to the Topic Microbes and Their Products for Sustainable Human Life)
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13 pages, 3977 KB  
Article
SiOx-Based Anode Materials with High Si Content Achieved Through Uniform Nano-Si Dispersion for Li-Ion Batteries
by Seunghyeok Jang and Jae-Hun Kim
Materials 2025, 18(14), 3272; https://doi.org/10.3390/ma18143272 - 11 Jul 2025
Viewed by 1285
Abstract
Silicon alloy-based materials are widely studied as high-capacity anode materials to replace commercial graphite in lithium-ion batteries (LIBs). Among these, silicon suboxide (SiOx) offers superior cycling performance compared to pure Si-based materials. However, achieving a high initial Coulombic efficiency (ICE) remains [...] Read more.
Silicon alloy-based materials are widely studied as high-capacity anode materials to replace commercial graphite in lithium-ion batteries (LIBs). Among these, silicon suboxide (SiOx) offers superior cycling performance compared to pure Si-based materials. However, achieving a high initial Coulombic efficiency (ICE) remains a key challenge. To address this, previous studies have explored SixO composites (x ≈ 1, 2), where nano-Si is uniformly dispersed within a Si suboxide matrix to enhance ICE. While this approach improves reversible capacity and ICE compared to conventional SiO, it still falls short of the capacity achieved with pure Si. This study employs a high-energy mechanical milling approach with increased Si content to achieve higher reversible capacity and further enhance the ICE while also examining the effects of trace oxygen uniformly distributed within the Si suboxide matrix. Structural characterization via X-ray diffraction, Raman spectroscopy, and electron microscopy confirm that Si crystallites (<10 nm) are homogeneously embedded within the SiOx matrix, reducing crystalline Si size and inducing partial amorphization. Electrochemical analysis demonstrates an ICE of 89% and a reversible capacity of 2558 mAh g−1, indicating significant performance improvements. Furthermore, carbon incorporation enhances cycling stability, underscoring the material’s potential for commercial applications. Full article
(This article belongs to the Special Issue High-Performance Materials for Energy Conversion)
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23 pages, 2680 KB  
Article
Novel Polymorphic Patterns for Elacestrant Dihydrochloride
by Zia Uddin Masum, P. Grant Spoors, Matt D. Burke and Vivek Gupta
Pharmaceutics 2025, 17(6), 745; https://doi.org/10.3390/pharmaceutics17060745 - 5 Jun 2025
Viewed by 1306
Abstract
Objective: This study expands on the polymorphic characterization of elacestrant dihydrochloride, developed by Stemline Therapeutics and approved by the FDA in 2023. The article focuses on more extensive polymorphism screening using various methods and solvents to discover the new polymorphism forms of this [...] Read more.
Objective: This study expands on the polymorphic characterization of elacestrant dihydrochloride, developed by Stemline Therapeutics and approved by the FDA in 2023. The article focuses on more extensive polymorphism screening using various methods and solvents to discover the new polymorphism forms of this molecule, besides identifying three polymorphic forms in the previously published studies. Methods: The crystalline and amorphous elacestrant hydrochloride solubility was assessed, and crystals were formed, followed by polymorph screening using 40 non-conventional solvents via different techniques to obtain the new polymorphic forms. XRPD, NMR, DSC, TGA, IC, and HPLC were used for solid-state characterization. Results: Patterns A, B, C, D, E, F, and G, and previously published forms 1,3, were identified in multiple studies during the extensive polymorphism screening using various methods and numerous solvent systems. Solid state characterization and purity analysis were completed using different relevant instruments. After the characterization, it was found that Pattern A was the most stable, like the desired/most stable Form 1, but it had fewer crystals; Pattern B is like Form 3 but a unique XRPD pattern; Pattern D is degradant; Pattern C, E, F, and G are considered as the new pattern of elacestrant along with patterns A and B. Conclusions: With XRPD, six new patterns (A, B, C, E, F, G) were identified. Patterns A, C, and E are promising crystalline candidates for further analysis and scale-up. Full article
(This article belongs to the Section Physical Pharmacy and Formulation)
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17 pages, 8604 KB  
Article
Design of Composite Systems Based on Hydrophilic Silica and Organic Acids: Gallic, Glycyrrhizic and Its Salts
by Tetiana Krupska, Qiliang Wei, Jinju Zheng, Weiyou Yang, Alina Holovan, Mykola Borysenko and Volodymyr Turov
J. Compos. Sci. 2025, 9(5), 247; https://doi.org/10.3390/jcs9050247 - 16 May 2025
Viewed by 642
Abstract
The process of formation of composite systems based on nanosilica A-300 and biologically active substances (BAS), namely gallic acid (GA), glycyrrhizic acid (GLA), and its salts, was studied using a set of physicochemical methods. It was shown that when BAS are immobilized on [...] Read more.
The process of formation of composite systems based on nanosilica A-300 and biologically active substances (BAS), namely gallic acid (GA), glycyrrhizic acid (GLA), and its salts, was studied using a set of physicochemical methods. It was shown that when BAS are immobilized on the silica surface by the method of joint grinding in a porcelain mortar, they pass into a nanosized X-ray amorphous state. Water adsorbed on the surface of such composite systems is also in a clustered state, and the radius of adsorbed water clusters is in the range of 0.4–50 nm. The chloroform environment has a complex effect on the size of water clusters. In general, there is a tendency for the radius of water clusters to increase when air is replaced by a chloroform environment. However, this does not always lead to a decrease in the interfacial energy. The possibility of the existence of metastable ice in the temperature range up to 287 K, stabilized by the surface of composite systems, was discovered. The amount of such ice can reach 20% of the total water content in the sample. The possibility of using complex viscosity measurements for hydrated silica powders and silica containing immobilized biologically active substances was shown. These measurements allow recording changes in the phase state of complex mixtures during the formation of compact composite forms under the influence of periodic mechanical loading. Full article
(This article belongs to the Special Issue Sustainable Biocomposites, 3rd Edition)
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21 pages, 5076 KB  
Article
Origanum vulgare ssp. hirtum: From Plant to 3D-Printed Gummies with Antioxidant and Anti-Inflammatory Properties
by Brayan J. Anaya, Lina Raudone, Isabel Ureña-Vacas, Amadeo Sanz-Perez, Mindaugas Marksa, Gabriele Vilkickyte, Juan José García-Rodríguez, Dolores R. Serrano and Elena González-Burgos
Gels 2025, 11(4), 246; https://doi.org/10.3390/gels11040246 - 26 Mar 2025
Cited by 1 | Viewed by 1163
Abstract
This study investigates the phytochemical profile, antioxidant and anti-inflammatory properties, and 3D-printing application of Origanum vulgare L. ssp. hirtum extract. The extract revealed a diverse range of phenolic compounds, with rosmarinic acid as the predominant compound (47.76%). The extract showed moderate to high [...] Read more.
This study investigates the phytochemical profile, antioxidant and anti-inflammatory properties, and 3D-printing application of Origanum vulgare L. ssp. hirtum extract. The extract revealed a diverse range of phenolic compounds, with rosmarinic acid as the predominant compound (47.76%). The extract showed moderate to high lipoxygenase inhibition (IC50 = 32.0 µg/mL), suggesting its potential as an anti-inflammatory agent. It also exhibited strong antioxidant activity, with hydrogen peroxide scavenging (SC50 = 99.2 µg/mL) and hydroxyl radical scavenging (IC50 = 64.12 µg/mL) capabilities. In cellular studies, high concentrations (50 µg/mL and 100 µg/mL) significantly decreased intracellular ROS production in Caco-2 cells (reductions exceeding 53% and 64%, respectively). Moreover, the extract suppressed NO production in LPS-stimulated J774A.1 macrophages in a concentration-dependent manner. The study also explores the incorporation of the extract into 3D-printed gummies. The gels exhibited a shear-thinning behavior, which was essential for successful extrusion-based 3D printing. The incorporation of Origanum extract significantly influenced the mechanical strength and compaction properties of the 3D-printed gummies before breaking (1.6-fold increase) allowing for a better mouth feeling. PXRD and FTIR analyses confirmed the amorphous nature of the 3D-printed gummies and the interaction between active ingredients and excipients utilized for printing. These findings demonstrated the potential for semisolid extrusion 3D printing at room temperature to transform a culinary herb (Origanum vulgare spp. hirtum) into a healthcare product with antioxidant and anti-inflammatory properties. Full article
(This article belongs to the Special Issue Synthesis, Characterization and Pharmaceutical Applications of Gels)
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16 pages, 986 KB  
Article
Formation of Ice Ih Clusters in Solid-Phase Glacial Water with Low Concentrations of Ca2⁺ and Mg2⁺ Ions
by Ignat Ignatov, Yordan G. Marinov, Paunka Vassileva, Teodora P. Popova, Georgi Gluhchev, Mario T. Iliev, Fabio Huether, Zhechko Dimitrov and Irina Gotova
Crystals 2025, 15(3), 254; https://doi.org/10.3390/cryst15030254 - 9 Mar 2025
Cited by 4 | Viewed by 1188
Abstract
This study explores the structural and chemical interactions between glacial water, ice Ih, and hydration clusters of divalent cations (Ca2⁺ and Mg2⁺). Ice Ih, with its hexagonal lattice and tetrahedral bonding network, is incompatible with [...] Read more.
This study explores the structural and chemical interactions between glacial water, ice Ih, and hydration clusters of divalent cations (Ca2⁺ and Mg2⁺). Ice Ih, with its hexagonal lattice and tetrahedral bonding network, is incompatible with the hydration shells of Ca2⁺ and Mg2⁺, which adopt octahedral geometries in aqueous solutions. During freezing, these hydration clusters become disordered, causing distortions in the ice structure. Slow freezing reduces these distortions, while rapid freezing traps ions in amorphous regions, preventing proper alignment of hydration clusters. Through advanced techniques such as chemical and isotopic analysis, computational modeling, and electrical impedance spectroscopy, this study examines ion exclusion mechanisms and water-clustering behaviors. The results show that both ions are largely excluded from the solid phase during freezing, with Mg2⁺ exhibiting stronger exclusion due to its smaller ionic radius and greater hydration energy. This study also highlights the role of sediments in modulating ion patterns in glacial ice. This work deepens our understanding of ion–ice interactions, offering insights for cryochemistry, hydrology, and environmental science. The integration of experimental and computational methods provides new perspectives on divalent cations’ role in modifying ice’s crystalline structure and explains isotopic variability in glacial waters. Full article
(This article belongs to the Section Inorganic Crystalline Materials)
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21 pages, 50829 KB  
Article
Strengthening the Cavitation Resistance of Cylinder Liners Using Surface Treatment with Electroless Ni-P (ENP) Plating and High-Temperature Heat Treatment
by Wenjuan Zhang, Hao Gao, Qianting Wang, Dong Liu and Enlai Zhang
Materials 2025, 18(5), 1087; https://doi.org/10.3390/ma18051087 - 28 Feb 2025
Cited by 1 | Viewed by 875
Abstract
As internal combustion engines (ICEs) develop towards higher explosion pressures and lower weights, their structures need to be more compact; thus, the wall thickness of their cylinder liners is reducing. However, intense vibrations in the cylinder liner can lead to coolant cavitation and, [...] Read more.
As internal combustion engines (ICEs) develop towards higher explosion pressures and lower weights, their structures need to be more compact; thus, the wall thickness of their cylinder liners is reducing. However, intense vibrations in the cylinder liner can lead to coolant cavitation and, in severe cases, penetration of the liner, posing a significant reliability issue for ICEs. Therefore, research on cylinder liner cavitation has attracted increasing interest. Gray cast iron is widely used in cylinder liners for its hardness and wear resistance; however, additional surface plating is necessary to improve cavitation resistance. This study developed a novel surface-modification technology using electroless Ni-P plating combined with high-temperature heat treatment to create cylinder liners with refined grains, low weight loss rate, and high hardness. The heat-treatment temperature ranged from 100 to 600 °C. An ultrasonic cavitation tester was used to simulate severe cavitation conditions, and we analyzed and compared Ni-P-plated and heat-treated Ni-P-plated surfaces. The findings showed that the combination of Ni-P plating with high-temperature heat treatment led to smoother, more refined surface grains and the formation of cellular granular structures. After heat treatment, the plating structure converted from amorphous to crystalline. From 100 to 600 °C, the weight loss of specimens was within the range of 0.162% to 0.573%, and the weight loss (80.2% lower than the plated surface) and weight loss rate at 600 °C were the smallest. Additionally, cavitation resistance improved by 80.1%. The microhardness of the heat-treated plated surface reached 895 HV at 600 °C, constituting a 306 HV (65.8%) increase compared with that of the unplated surface, and a 560 HV increase compared with that of the maximum hardness of the plated surface without heat treatment of 335 HV, with an enhancement rate of 62.6%. Full article
(This article belongs to the Special Issue Research on Performance Improvement of Advanced Alloys)
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25 pages, 12864 KB  
Article
Polysaccharides from Exocarpium Citri Grandis: Graded Ethanol Precipitation, Structural Characterization, Inhibition of α-Glucosidase Activity, Anti-Oxidation, and Anti-Glycation Potentials
by Meizhen Chen and Juan Wang
Foods 2025, 14(5), 791; https://doi.org/10.3390/foods14050791 - 25 Feb 2025
Cited by 2 | Viewed by 2049
Abstract
The endocarp of Exocarpium Citri Grandis (ECG) is abundant in various bioactive components, such as polysaccharides; however, there are few studies on them. Thus, it is highly necessary to carry out further research on the structural characterization and biological activities of ECG polysaccharides [...] Read more.
The endocarp of Exocarpium Citri Grandis (ECG) is abundant in various bioactive components, such as polysaccharides; however, there are few studies on them. Thus, it is highly necessary to carry out further research on the structural characterization and biological activities of ECG polysaccharides (EPs), which are important bioactive substances. In this study, water-extracted EPs were precipitated by ethanol with final concentrations of 50%, 70%, and 90% (v/v), respectively. Three crude polysaccharides (EP50, EP70, and EP90) were fractioned successively. The three polysaccharide fractions were structurally elucidated and were investigated in vitro for their biological activities related to glucose metabolism containing inhibitory effects on α-glucosidase and non-enzymatic glycosylation and their antioxidant capacities. The main results are summarized as follows: (1) Gradient ethanol precipitation and physicochemical properties of EPs: The yields of EP50, EP70, and EP90 were 11.18%, 0.57%, and 0.18%, respectively. The total sugar contents were 40.01%, 52.61%, and 53.46%, and the uronic acid contents were 30.25%, 18.11%, and 8.17%, respectively. In addition, the three fractions had the same composition of monosaccharides, including rhamnose, arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid, with differences in the content of neutral and acidic monosaccharides. They all may be branched polymers and spherical conformation, and they were acidic polysaccharides containing esterified and non-esterified uronic acids, pyranose-form sugars, and glycosidic linkages of α-configuration and β-configuration, with esterification degrees of 32.25%, 28.82%, and 15.58%, respectively. Meanwhile, EP50, EP70, and EP90 were mainly amorphous, and the molecular conformation in solution was a spherical branching polymer without a triple helix structure. The EPs exhibited excellent thermal stability, with their structures remaining stable below 170 °C. (2) In terms of activity research, the results showed that EPs had a good α-glucosidase inhibitory effect with IC50 values of 1.17 mg/mL, 1.40 mg/mL, and 2.72 mg/mL, respectively, among which EP50 was the best. EP50, EP70, and EP90 displayed antioxidant activity by scavenging DPPH and ABTS radicals as well as oxygen radical absorbance capacity. Among them, EP90 had the strongest antioxidant activity. Furthermore, the EPs showed prominent effects on the inhibitory activity of non-enzymatic glycosylation. In summary, the research on the extraction of polysaccharide from ECG provides a technical reference for the further utilization of ECG resources. This study on antioxidant activity provides theoretical support for their use as a natural antioxidant. As oxidation and glycation are relevant to diabetic complications, the result of this work suggests that EPs may be effective in preventing and treating diabetic complications. Full article
(This article belongs to the Section Food Engineering and Technology)
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17 pages, 2752 KB  
Article
Can Implicit Solvation Methods Capture Temperature Effects on the Infrared Features of Astrophysical Ices?
by Daniel A. B. Oliveira, Víctor S. A. Bonfim, Felipe Fantuzzi and Sergio Pilling
Photochem 2025, 5(1), 5; https://doi.org/10.3390/photochem5010005 - 14 Feb 2025
Viewed by 1027
Abstract
Astrophysical ices play a crucial role in the chemistry of cold interstellar environments. However, their diverse compositions, temperatures, and grain morphologies pose significant challenges for molecular identification and quantification through infrared observations. We investigate the ability of implicit solvation approaches to capture temperature-dependent [...] Read more.
Astrophysical ices play a crucial role in the chemistry of cold interstellar environments. However, their diverse compositions, temperatures, and grain morphologies pose significant challenges for molecular identification and quantification through infrared observations. We investigate the ability of implicit solvation approaches to capture temperature-dependent infrared spectral features of CO2 molecules embedded in astrophysical ice analogues, comparing their performance to that of explicit ice models and experimental data. Using DFT calculations and vibrational frequency scaling, we model CO2 trapped in both amorphous (cold) and crystalline (warm) H2O ice clusters. The implicit model qualitatively identifies certain trends but fails to reliably capture the magnitude of frequency shifts and band strengths. Explicit models correctly reproduce the gas-to-solid redshifts for both the asymmetric stretch and bending modes; however, neither approach successfully replicates the experimentally observed temperature-dependent trend in the bending mode. While continuum-like methods may be useful as first-order approximations, explicit modelling of the molecular environment is essential for accurately simulating the infrared spectral behaviour of CO2 in astrophysical ices and for interpreting observational data on ice composition and evolution. Full article
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13 pages, 2687 KB  
Article
Quantitative Modeling of High-Energy Electron Scattering in Thick Samples Using Monte Carlo Techniques
by Bradyn Quintard, Xi Yang and Liguo Wang
Appl. Sci. 2025, 15(2), 565; https://doi.org/10.3390/app15020565 - 9 Jan 2025
Cited by 1 | Viewed by 1362
Abstract
Cryo-electron microscopy (cryo-EM) is a powerful tool for imaging biological samples but is typically limited by sample thickness, which is restricted to a few hundred nanometers depending on the electron energy. However, there is a growing need for imaging techniques capable of studying [...] Read more.
Cryo-electron microscopy (cryo-EM) is a powerful tool for imaging biological samples but is typically limited by sample thickness, which is restricted to a few hundred nanometers depending on the electron energy. However, there is a growing need for imaging techniques capable of studying biological samples up to 10 µm in thickness while maintaining nanoscale resolution. This need motivates the use of mega-electron-volt scanning transmission electron microscopy (MeV-STEM), which leverages the high penetration power of MeV electrons to generate high-resolution images of thicker samples. In this study, we employ Monte Carlo simulations to model electron–sample interactions and explore the signal decay of imaging electrons through thick specimens. By incorporating material properties, interaction cross-sections for energy loss, and experimental parameters, we investigate the relationship between the incident and transmitted beam intensities. Key factors such as detector collection angle, convergence semi-angle, and the material properties of samples were analyzed. Our results demonstrate that the relationship between incident and transmitted beam intensities follows the Beer–Lambert law over thicknesses ranging from a few microns to several tens of microns, depending on material composition, electron energy, and collection angles. The linear depth of silicon dioxide reaches 3.9 µm at 3 MeV, about 6 times higher than that at 300 keV. Meanwhile, the linear depth of amorphous ice reaches 17.9 µm at 3 MeV, approximately 11.5 times higher than that at 300 keV. These findings are crucial for advancing the study of thick biological and semiconductor samples using MeV-STEM. Full article
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17 pages, 6110 KB  
Article
Simulation Study of High-Precision Characterization of MeV Electron Interactions for Advanced Nano-Imaging of Thick Biological Samples and Microchips
by Xi Yang, Liguo Wang, Victor Smaluk, Timur Shaftan, Tianyi Wang, Nathalie Bouet, Gabriele D’Amen, Weishi Wan and Pietro Musumeci
Nanomaterials 2024, 14(22), 1797; https://doi.org/10.3390/nano14221797 - 8 Nov 2024
Cited by 2 | Viewed by 1348
Abstract
The resolution of a mega-electron-volt scanning transmission electron microscope (MeV-STEM) is primarily governed by the properties of the incident electron beam and angular broadening effects that occur within thick biological samples and microchips. A precise understanding and mitigation of these constraints require detailed [...] Read more.
The resolution of a mega-electron-volt scanning transmission electron microscope (MeV-STEM) is primarily governed by the properties of the incident electron beam and angular broadening effects that occur within thick biological samples and microchips. A precise understanding and mitigation of these constraints require detailed knowledge of beam emittance, aberrations in the STEM column optics, and energy-dependent elastic and inelastic critical angles of the materials being examined. This simulation study proposes a standardized experimental framework for comprehensively assessing beam intensity, divergence, and size at the sample exit. This framework aims to characterize electron-sample interactions, reconcile discrepancies among analytical models, and validate Monte Carlo (MC) simulations for enhanced predictive accuracy. Our numerical findings demonstrate that precise measurements of these parameters, especially angular broadening, are not only feasible but also essential for optimizing imaging resolution in thick biological samples and microchips. By utilizing an electron source with minimal emittance and tailored beam characteristics, along with amorphous ice and silicon samples as biological proxies and microchip materials, this research seeks to optimize electron beam energy by focusing on parameters to improve the resolution in MeV-STEM/TEM. This optimization is particularly crucial for in situ imaging of thick biological samples and for examining microchip defects with nanometer resolutions. Our ultimate goal is to develop a comprehensive mapping of the minimum electron energy required to achieve a nanoscale resolution, taking into account variations in sample thickness, composition, and imaging mode. Full article
(This article belongs to the Special Issue The Interaction of Electron Phenomena on the Mesoscopic Scale)
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18 pages, 42832 KB  
Article
Influence of the Crystal Forms of Calcium Carbonate on the Preparation and Characteristics of Indigo Carmine-Calcium Carbonate Lake
by Le Jing, Yuhan Liu, Jiaqi Cui, Jinghan Ma, Dongdong Yuan and Chengtao Wang
Foods 2024, 13(16), 2607; https://doi.org/10.3390/foods13162607 - 20 Aug 2024
Cited by 3 | Viewed by 1759
Abstract
In this study, indigo carmine (IC)-calcium carbonate lakes with different crystalline forms of calcium carbonate were prepared through co-precipitation methods, and the properties of these lakes and their formation mechanisms were investigated. The results showed that amorphous calcium carbonate (ACC) exhibited the smallest [...] Read more.
In this study, indigo carmine (IC)-calcium carbonate lakes with different crystalline forms of calcium carbonate were prepared through co-precipitation methods, and the properties of these lakes and their formation mechanisms were investigated. The results showed that amorphous calcium carbonate (ACC) exhibited the smallest particle size and the largest specific surface area, resulting in the highest adsorption efficiency. Vaterite, calcite, and aragonite followed after ACC in decreasing order of adsorption efficiency. Kinetic analysis and isothermal analysis revealed the occurrence of chemisorption and multilayer adsorption during formation of the lakes. The FTIR and Raman spectra suggested participation of sulfonic acid groups in chemisorption. Appearance of IC significantly altered TGA curves by changing weight loss rate before decomposition of calcium carbonate. EDS analysis revealed the adsorption of IC predominantly happened on the surface of calcium carbonate particles rather than the interior. Full article
(This article belongs to the Section Food Physics and (Bio)Chemistry)
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22 pages, 4138 KB  
Article
Mechanochemical Approach to Obtaining a Multicomponent Fisetin Delivery System Improving Its Solubility and Biological Activity
by Natalia Rosiak, Ewa Tykarska and Judyta Cielecka-Piontek
Int. J. Mol. Sci. 2024, 25(7), 3648; https://doi.org/10.3390/ijms25073648 - 25 Mar 2024
Cited by 8 | Viewed by 2639
Abstract
In this study, binary amorphous solid dispersions (ASDs, fisetin-Eudragit®) and ternary amorphous solid inclusions (ASIs, fisetin-Eudragit®-HP-β-cyclodextrin) of fisetin (FIS) were prepared by the mechanochemical method without solvent. The amorphous nature of FIS in ASDs and ASIs was confirmed using [...] Read more.
In this study, binary amorphous solid dispersions (ASDs, fisetin-Eudragit®) and ternary amorphous solid inclusions (ASIs, fisetin-Eudragit®-HP-β-cyclodextrin) of fisetin (FIS) were prepared by the mechanochemical method without solvent. The amorphous nature of FIS in ASDs and ASIs was confirmed using XRPD (X-ray powder diffraction). DSC (Differential scanning calorimetry) confirmed full miscibility of multicomponent delivery systems. FT-IR (Fourier-transform infrared analysis) confirmed interactions that stabilize FIS’s amorphous state and identified the functional groups involved. The study culminated in evaluating the impact of amorphization on water solubility and conducting in vitro antioxidant assays: 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)—ABTS, 2,2-diphenyl-1-picrylhydrazyl—DPPH, Cupric Reducing Antioxidant Capacity—CUPRAC, and Ferric Reducing Antioxidant Power—FRAP and in vitro neuroprotective assays: inhibition of acetylcholinesterase—AChE and butyrylcholinesterase—BChE. In addition, molecular docking allowed for the determination of possible bonds and interactions between FIS and the mentioned above enzymes. The best preparation turned out to be ASI_30_EPO (ASD fisetin-Eudragit® containing 30% FIS in combination with HP-β-cyclodextrin), which showed an improvement in apparent solubility (126.5 ± 0.1 µg∙mL−1) and antioxidant properties (ABTS: IC50 = 10.25 µg∙mL−1, DPPH: IC50 = 27.69 µg∙mL−1, CUPRAC: IC0.5 = 9.52 µg∙mL−1, FRAP: IC0.5 = 8.56 µg∙mL−1) and neuroprotective properties (inhibition AChE: 39.91%, and BChE: 42.62%). Full article
(This article belongs to the Special Issue New Insights in Natural Bioactive Compounds: 3rd Edition)
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16 pages, 3917 KB  
Article
3D-Printed Chitosan-Based Scaffolds with Scutellariae baicalensis Extract for Dental Applications
by Magdalena Paczkowska-Walendowska, Ioanna Koumentakou, Maria Lazaridou, Dimitrios Bikiaris, Andrzej Miklaszewski, Tomasz Plech and Judyta Cielecka-Piontek
Pharmaceutics 2024, 16(3), 359; https://doi.org/10.3390/pharmaceutics16030359 - 4 Mar 2024
Cited by 16 | Viewed by 3026
Abstract
The plant material Scutellariae baicalensis radix, which is rich in flavones (baicalin), possesses antibacterial, antifungal, antioxidant, and anti-inflammatory properties. This work aimed to develop a 3D-printed chitosan-based hydrogel rich in Scutellariae baicalensis extract as an innovative approach for the personalized treatment of [...] Read more.
The plant material Scutellariae baicalensis radix, which is rich in flavones (baicalin), possesses antibacterial, antifungal, antioxidant, and anti-inflammatory properties. This work aimed to develop a 3D-printed chitosan-based hydrogel rich in Scutellariae baicalensis extract as an innovative approach for the personalized treatment of periodontal diseases. Chitosan-based hydrogels were prepared, and the printability of the prepared hydrogels was determined. The hydrogel with 2.5% w/v of high molecular-weight chitosan (CS), 2% w/v gelatin (Gel), and 10% w/w of extract (Ex) presented the best printability, producing smooth and uniform scaffolds. It was proved that the CS/Gel/Ex hydrogel was stabilized by hydrogen bonds and remained in amorphous dispersion in the 3D-printed structures (confirmed by ATR-FTIR and XRPD). Due to the amorphization of the active substance, a significant increase in the release of baicalin in vitro was observed. It was demonstrated that there was an initial burst release and a continuous release profile (n = 3). Higuchi kinetic was the most likely baicalin release kinetic. The second fit, the Korsmeyer–Peppas kinetics model, showed coupled diffusion of the active ingredient in the hydrated matrix and polymer relaxation regulated release, with n values ranging from 0.45 to 0.89. The anti-inflammatory properties of 3D-printed scaffolds were assessed as the ability to inhibit the activity of the hyaluronidase enzyme. Activity was assessed as IC50 = 63.57 ± 4.98 mg hydrogel/mL (n = 6). Cytotoxicity tests demonstrated the biocompatibility of the material. After 24 h of exposure to the 2.5CS/2Gel/10Ex scaffold, fibroblasts migrated toward the scratch, closed the “wound” by 97.1%, and significantly accelerated the wound healing process. The results render the 3D-printed CS/Gel/extract scaffolds as potential candidates for treating periodontal diseases. Full article
(This article belongs to the Section Pharmaceutical Technology, Manufacturing and Devices)
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