8,351 results on '"silica nanoparticles"'
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2. Morphological characteristics of silica nanoparticles derived from rice husk for expected agricultural application.
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Trinh, Thong Quang, Mai, Lan Thi, Le, Dang Hai, Bon, Volodymyr, Simon, Frank, Löffler, Markus, Rellinghaus, Bernd, Al Aiti, Muhannad, and Cuniberti, Gianaurelio
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SILICA nanoparticles , *ZETA potential , *RICE hulls , *RENEWABLE natural resources , *SOIL quality - Abstract
The study aimed to apply biosilica nanoparticles from renewable resources for improving soil quality as a type of fertilizer carier. The silica particles having a purity of about 98 % were extracted from rice husk at the calcination temperatures of 550 °C, 600 °C, 650 °C, and 700 °C. The required materials properties were investigated by advanced measurement techniques. All samples showed the amorphous structure with Si–O–Si bond and the particles' agglomeration with the average size of 10–50 nm and principle electronic structures with the typical spectra of Si and O 2. When the synthesized silica was used as the medium to release absorbed nutrients in a controlled manner, surface properties, including the Brunauer–Emmett–Teller area and the average pore diameter were evaluated between 179 m2/g to 570 m2/g, and 4 nm–40 nm, respectively. The measured electrokinetic potential of the synthesized particles was between −20 mV and −36 mV guaranteeing the stability when they are dispersed in the aqueous environment. The experimental results showed that the silica particles calcinated at 650 °C had the best properties. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Quasi-in-situ characterization and laser damage investigation of flaws in silica antireflection coatings.
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Yan, Hongwei, Liu, Taixiang, Huang, Lin, Yang, Ke, Li, Changpeng, Zhang, Zhuo, and Qian, Yujie
- Abstract
Silica sol-gel antireflection coatings are used in high-power lasers due to their excellent laser damage resistance. These coatings are prepared using silica nanoparticles, and flaws generated during the coating preparation process are considered one of the factors that can lead to laser damage. Ring-shape flaws of micrometer-size usually appear on the surface of silica sol-gel antireflection coating. The morphologies of these flaws were investigated through optical microscopy, contact-type surface profilometer and scanning electron microscope. The diameters of the ring-shape flaws are from several micrometers to tens of micrometers. It has been demonstrated that the ring-shape flaws are nodule-like structures containing closely packed silica nanoparticles. The quasi-in-situ laser damage tests of the coated samples show the ring-shape flaws have a low damage probability. The formation of ring-shape flaws on the silica sol-gel coating is related to the polydispersity of the colloidal silica nanoparticles. Through the analysis of the size distribution of silica nanoparticles, a mechanism for flaws formation is proposed. Highlights: Morphologies of the ring-shape flaws on the surface of silica sol-gel antireflection coating. Quasi-in-situ laser damage tests of the ring-shape flaws on the silica coating. Formation mechanism of the ring-shape flaws on the silica sol-gel coating. [ABSTRACT FROM AUTHOR]
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- 2024
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4. The crucial role of hydroxyethyl methacrylate in the sintering of fused silica glass using ultraviolet-cured silica nanoparticle slurries: dispersing nanoparticles.
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Hu, Youwang, Wang, Guilin, Zhang, Qinglong, Sun, Xiaoyan, and Chen, Haikuan
- Abstract
Fused silica glass is prepared by dispersing silica nanoparticles (SiNPs) through the hydroxyethyl methacrylate (HEMA). The dispersion of SiNPs was characterized using transmission electron microscopy and small angle X-ray scattering. The rheological properties and functional groups of SiNP slurries were analyzed utilizing a rotational rheometer and fourier transform infrared spectroscopy. The sintering quality of the fused silica glass was characterized through scanning electron microscopy and X-ray diffraction. The research results show that HEMA adsorbs on the surface of SiNP through hydrogen bonding to form a solvation layer of a certain thickness, thereby hindering the agglomeration of SiNPs. The SiNP slurry system exhibits bi-fractal properties. The viscosity and shear stress of the SiNP slurry initially decrease and then increase with increasing HEMA content. Achieving a homogeneous dispersion of SiNPs in the slurry is essential for sintering high-quality silica glass. The internal voids of agglomerates are the origin of crack formation. Highlights: The mechanism of dispersing silica nanoparticles by hydroxyethyl methacrylate (HEMA) was deeply investigated. The microstructure and rheological properties of silica nanoparticle slurries were analyzed. The effect of HEMA content on the sintering quality of fused silica glass was studied. The formation and origin of cracks during the sintering of fused silica glass were revealed. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Scalable Jet‐Based Fabrication of PEI‐Hydrogel Particles for CO2 Capture.
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Jiang, Jieke, van Daatselaar, Eline, Wijnja, Hylke, de Koning Gans, Tessa, Schellevis, Michel, Venner, Cornelis H., Brilman, Derk W.F., and Visser, Claas Willem
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CARBON sequestration ,NANOGELS ,MASS transfer ,SILICA nanoparticles ,FLUE gases - Abstract
The capture, regeneration, and conversion of CO2 from ambient air and flue gas streams are critical aspects of mitigating global warming. Solid sorbents for CO2 absorption are very promising as they have high mass transfer areas without energy input and reduce emissions and minimize corrosion as compared to liquid sorbents. However, precisely tunable solid CO2 sorbents are difficult to produce. Here, we demonstrate the high‐throughput production of hydrogel‐based CO2‐absorbing particles via liquid jetting. By wrapping a liquid jet consisting of an aqueous solution of cross‐linkable branched polyethylenimine (PEI) with a layer of suspension containing hydrophobic silica nanoparticles, monodisperse droplets with a silica nanoparticle coating layer was formed in the air. A stable Pickering emulsion containing PEI droplets was obtained after these ejected droplets were collected in a heated oil bath. The droplets turn into mm‐sized particles after thermal curing in the bath. The diameter, PEI content, and silica content of the particles were systematically varied, and their CO2 absorption was measured as a function of time. Steam regeneration of the particles enabled cyclic testing, revealing a CO2 absorption capacity of 6.5 ± 0.5 mol kg−1 solid PEI in pure CO2 environments and 0.7 ± 0.3 mol kg−1 solid PEI for direct air capture. Several thousands of particles were produced per second at a rate of around 0.5 kg per hour, with a single nozzle. This process can be further scaled by parallelization. The complete toolbox for the design, fabrication, testing, and regeneration of functional hydrogel particles provides a powerful route toward novel solid sorbents for regenerative CO2 capture. [ABSTRACT FROM AUTHOR]
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- 2024
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6. WRN Nuclease‐Mediated EcDNA Clearance Enhances Antitumor Therapy in Conjunction with Trehalose Dimycolate/Mesoporous Silica Nanoparticles.
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Li, Yinan, Huang, Xiu, Li, Yingying, Qiao, Qingqing, Chen, Caihong, Chen, Yang, Zhong, Weilong, Liu, Huijuan, and Sun, Tao
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EXTRACHROMOSOMAL DNA , *PULMONARY fibrosis , *MESOPOROUS silica , *SILICA nanoparticles , *CELL transformation - Abstract
Current research on tumor fibrosis has focused on cancer‐associated fibroblasts, which may exert dual functions of tumor promotion and inhibition. Little attention has been paid to whether tumor cells themselves can undergo fibrotic transformation and whether they can inhibit parenchymal cells similar to pulmonary fibrosis, thus achieving the goal of inhibiting the malignant progression of tumors. To explore the significance of inducing tumor fibrosis for cancer treatment. This study utilizes mesoporous silica nanoparticles (MSN) loaded with Trehalose dimycolate (TDM) to induce tumor cell fibrosis through the dual effects of TDM‐induced inflammatory granuloma and MSN‐induced foreign body granuloma. The results show that TDM/MSN (TM) can effectively induce tumor fibrosis, manifested specifically by collagen internalization, and suppression of proliferation and invasion capabilities, suggesting the potential role of tumor fibrosis therapy. However, further investigation reveals that extrachromosomal DNA (ecDNA) mediates resistance to fibrosis induction. To comprehensively enhance the efficacy, WRN exonuclease is conjugated to TM to form new nanoparticles (TMW) capable of effectively eliminating ecDNA, globally promoting tumor cell fibroblast‐like transformation, and validated in a PDX model to inhibit cancer progression. Therefore, TMW, through inducing tumor cell fibrosis to inhibit its malignant progression, holds great potential as a clinical treatment strategy. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Stabilizing Bicontinuous Emulsions with Sub‐Micrometer Domains Solely by Nanoparticles.
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Sprockel, Alessio J., Vrijhoeven, Tessa N., Siegel, Henrik, Steenvoorden, Ffion E., and Haase, Martin F.
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CHEMICAL reactors , *SILICA nanoparticles , *MEMBRANE separation , *NUCLEAR reactor materials , *NANOPARTICLES - Abstract
Nanoparticle‐stabilized, bicontinuous interfacially jammed emulsion gels (bijels) find potential applications as battery, separation membrane, and chemical reactor materials. Decreasing the liquid domain sizes of bijels to sub‐micrometer dimensions requires surfactants, complicating bijel synthesis and postprocessing into functional nanomaterials. This work introduces surfactant‐free bijels with sub‐micrometer domains, solely stabilized by nanoparticles. To this end, the covalent surface functionalization of silica nanoparticles is characterized by thermogravimetric analysis, mass spectrometry, Fourier‐transform infrared spectroscopy, and contact angle measurements. Bijels are generated with the functionalized nanoparticles via solvent transfer induced phase separation (STrIPS), enabling the optimization of nanoparticle functionalization and surface ionization. Nanoparticles of intermediate functionalization and controlled negative surface charge stabilize bijels with sub‐micrometer liquid domains. This remarkable control over bijel synthesis provides urgently needed progress to facilitate the widespread implementation of bijels as nanomaterials in research and applications. [ABSTRACT FROM AUTHOR]
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- 2024
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8. An Injectable IPN Nanocomposite Hydrogel Embedding Nano Silica for Tissue Engineering Application.
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Kakapour, Ali, Nouri Khorasani, Saied, Khalili, Shahla, Hafezi, Mahshid, Sattari‐Najafabadi, Mehdi, Najarzadegan, Mahsa, Saleki, Samin, and Bagheri‐Khoulenjani, Shadab
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BIOPRINTING , *POLYMER networks , *RHEOLOGY , *SILICA nanoparticles , *TISSUE engineering - Abstract
Gelatin methacrylate (GM) and sodium alginate (SA) are two biomaterials that have been widely employed in tissue engineering, particularly in 3D bioprinting. However, they have some drawbacks including undesirable physico‐mechanical properties and printability, hindering their application. This work developed an interpenetrating polymeric network (IPN) of GM and SA reinforced with silica nanoparticles (SNPs) to deal with hydrogels’ drawbacks. Besides, for cross‐linking, visible light is used as an alternative to UV light to prevent disruptions in cellular metabolism and immune system reactions. Four GM/SA/SNP hydrogels different in SNPs concentration (0, 0.5, 1, and 2 w/w%) are studied. The performance of the hydrogels is evaluated in terms of physico‐mechanical properties (viscoelasticity, compressive modulus, degradation, and swelling), rheological properties, and biological properties (fibroblast cell growth and adhesion, and MTT assay). The results demonstrated that the GM/SA/SNP hydrogel with 1% SNPs provided desirable physical (645% swelling and 59.3% degradation), mechanical strength (270 kPa), rheological (tan δ of almost 0.14), and biological performances (≈98% viability after 3 days) while maintaining appropriate printability. The findings suggest that the GM/SA/SNP hydrogel holds great potential for applications in soft tissue regeneration. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Highly sensitive multiplexed colorimetric lateral flow immunoassay by plasmon-controlled metal–silica isoform nanocomposites: PINs.
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Shin, Minsup, Kim, Wooyeon, Yoo, Kwanghee, Cho, Hye-Seong, Jang, Sohyeon, Bae, Han-Joo, An, Jaehyun, Lee, Jong-chan, Chang, Hyejin, Kim, Dong-Eun, Kim, Jaehi, Lee, Luke P., and Jun, Bong-Hyun
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METAL nanoparticles ,GOLD nanoparticles ,SILICA nanoparticles ,NANOPARTICLES analysis ,RESONANCE effect - Abstract
Lateral flow assay (LFA) systems use metal nanoparticles for rapid and convenient target detection and are extensively studied for the diagnostics of various diseases. Gold nanoparticles (AuNPs) are often used as probes in LFAs, displaying a single red color. However, there is a high demand for colorimetric LFAs to detect multiple biomarkers, requiring the use of multicolored NPs. Here, we present a highly sensitive multiplexed colorimetric lateral flow immunoassay by multicolored Plasmon-controlled metal–silica Isoform Nanocomposites (PINs). We utilized the localized surface plasmon resonance effect to create multi-colored PINs by precisely adjusting the distance between the NPs on the surface of PINs through the controlled addition of reduced gold and silver precursors. Through simulations, we also confirmed that the distance between nanoparticles on the surface of PINs significantly affects the color and colorimetric signal intensity of the PINs. We achieved multicolored PINs that exhibit stronger colorimetric signals, offering a new solution for LFA detection with high sensitivity and a 33 times reduced limit of detection (LOD) while maintaining consistent size deviations within 5%. We expect that our PINs-based colorimetric LFA will facilitate the sensitive and simultaneous detection of multiple biomarkers in point-of-care testing. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Fumed-Si-Pr-Ald-Barb as a Fluorescent Chemosensor for the Hg 2+ Detection and Cr 2 O 7 2− Ions: A Combined Experimental and Computational Perspective.
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Mohammadi Ziarani, Ghodsi, Rezakhani, Mahtab, Feizi-Dehnayebi, Mehran, and Nikolova, Stoyanka
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SILICA nanoparticles , *MOLECULAR orbitals , *BAND gaps , *X-ray diffraction , *DETECTION limit - Abstract
The surface of fumed silica nanoparticles was modified by pyridine carbaldehyde and barbituric acid to provide fumed-Si-Pr-Ald-Barb. The structure was identified and investigated through diverse techniques, such as FT-IR, EDX, Mapping, BET, XRD, SEM, and TGA. This nanocomposite was used to detect different cations and anions in a mixture of H2O:EtOH. The results showed that fumed-Si-Pr-Ald-Barb can selectively detect Hg2+ and Cr2O72− ions. The detection limits were calculated at about 5.4 × 10−3 M for Hg2+ and 3.3 × 10−3 M for Cr2O72− ions. A computational method (DFT) was applied to determine the active sites on the Pr-Ald-Barb for electrophilic and nucleophilic attacks. The HOMO-LUMO molecular orbital was calculated by B3LYP/6-311G(d,p)/LANL2DZ theoretical methods. The energy gap for the Pr-Ald-Barb and Pr-Ald-Barb+ion complexes was predicted by the EHOMO and ELUMO values. The DFT calculation confirms the suggested experimental mechanism for interacting the Pr-Ald-Barb with ions. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Taurine Protects against Silica Nanoparticle-Induced Apoptosis and Inflammatory Response via Inhibition of Oxidative Stress in Porcine Ovarian Granulosa Cells.
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Chen, Fenglei, Sun, Jiarong, Ye, Rongrong, Virk, Tuba Latif, Liu, Qi, Yuan, Yuguo, and Xu, Xianyu
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GRANULOSA cells , *PYROPTOSIS , *SILICA nanoparticles , *CYTOTOXINS , *GENETIC transcription - Abstract
Simple Summary: Taurine (Tau) is a well-known antioxidant. However, the protective effects of Tau against silica nanoparticle (SNP)-induced reproductive toxicity still remain unexplored. So this study reveals the effect of Tau on SNP-induced porcine ovarian granulosa cell toxicity. SNPs trigger oxidative stress through excessive ROS production, leading to inflammation and cell apoptosis in porcine ovarian granulosa cells. Tau mitigates SNP-induced cytotoxicity by reducing oxidative stress, inflammatory response, and mitochondria-mediated cell apoptosis in porcine ovarian granulosa cells. Therefore, Tau could be an effective strategy to alleviate SNP-induced toxicity and holds promising application prospects in the animal husbandry and veterinary industry. Silica nanoparticles (SNPs) induce reproductive toxicity through ROS production, which significantly limits their application. The protective effects of taurine (Tau) against SNP-induced reproductive toxicity remain unexplored. So this study aims to investigate the impact of Tau on SNP-induced porcine ovarian granulosa cell toxicity. In vitro, granulosa cells were exposed to SNPs combined with Tau. The localization of SNPs was determined by TEM. Cell viability was examined by CCK-8 assay. ROS levels were measured by CLSM and FCM. SOD and CAT levels were evaluated using ELISA and qPCR. Cell apoptosis was detected by FCM, and pro-inflammatory cytokine transcription levels were measured by qPCR. The results showed that SNPs significantly decreased cell viability, while increased cell apoptosis and ROS levels. Moreover, SOD and CAT were decreased, while IFN-α, IFN-β, IL-1β, and IL-6 were increased after SNP exposures. Tau significantly decreased intracellular ROS, while it increased SOD and CAT compared to SNPs alone. Additionally, Tau exhibited anti-inflammatory effects and inhibited cell apoptosis. On the whole, these findings suggest that Tau mitigates SNP-induced cytotoxicity by reducing oxidative stress, inflammatory response, and cell apoptosis. Tau may be an effective strategy to alleviate SNP-induced toxicity and holds promising application prospects in the animal husbandry and veterinary industry. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Effects of Silica Nanoparticles on the Piezoelectro-Elastic Response of PZT-7A–Polyimide Nanocomposites: Micromechanics Modeling Technique.
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Umer, Usama, Abidi, Mustufa Haider, Mian, Syed Hammad, Alasim, Fahad, and Aboudaif, Mohammed K.
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SILICA nanoparticles , *NANOPARTICLES , *ELASTIC constants , *MODULUS of rigidity , *RENEWABLE energy sources , *POLYIMIDES - Abstract
By using piezoelectric materials, it is possible to convert clean and renewable energy sources into electrical energy. In this paper, the effect on the piezoelectro-elastic response of piezoelectric-fiber-reinforced nanocomposites by adding silica nanoparticles into the polyimide matrix is investigated by a micromechanical method. First, the Ji and Mori–Tanaka models are used to calculate the properties of the nanoscale silica-filled polymer. The nanoparticle agglomeration and silica–polymer interphase are considered in the micromechanical modeling. Then, considering the filled polymer as the matrix and the piezoelectric fiber as the reinforcement, the Mori–Tanaka model is used to estimate the elastic and piezoelectric constants of the piezoelectric fibrous nanocomposites. It was found that adding silica nanoparticles into the polymer improves the elastic and piezoelectric properties of the piezoelectric fibrous nanocomposites. When the fiber volume fraction is 60%, the nanocomposite with the 3% silica-filled polyimide exhibits 39%, 31.8%, and 37% improvements in the transverse Young's modulus E T , transverse shear modulus G T L , and piezoelectric coefficient e 31 in comparison with the composite without nanoparticles. Furthermore, the piezoelectro-elastic properties such as E T , G T L , and e 31 can be improved as the nanoparticle diameter decreases. However, the elastic and piezoelectric constants of the piezoelectric fibrous nanocomposites decrease once the nanoparticles are agglomerated in the polymer matrix. A thick interphase with a high stiffness enhances the nanocomposite's piezoelectro-elastic performance. Also, the influence of volume fractions of the silica nanoparticles and piezoelectric fibers on the nanocomposite properties is studied. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Stress-Responsive Gene Expression, Metabolic, Physiological, and Agronomic Responses by Consortium Nano-Silica with Trichoderma against Drought Stress in Bread Wheat.
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Aljeddani, Ghalia S., Hamouda, Ragaa A., Abdelsattar, Amal M., and Heikal, Yasmin M.
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DROUGHT tolerance , *RICE hulls , *PHYTOPATHOGENIC fungi , *SILICA nanoparticles , *TRICHODERMA harzianum - Abstract
The exploitation of drought is a critical worldwide challenge that influences wheat growth and productivity. This study aimed to investigate a synergistic amendment strategy for drought using the single and combined application of plant growth-promoting microorganisms (PGPM) (Trichoderma harzianum) and biogenic silica nanoparticles (SiO2NPs) from rice husk ash (RHA) on Saudi Arabia's Spring wheat Summit cultivar (Triticum aestivum L.) for 102 DAS (days after sowing). The significant improvement was due to the application of 600 ppm SiO2NPs and T. harzianum + 600 ppm SiO2NPs, which enhanced the physiological properties of chlorophyll a, carotenoids, total pigments, osmolytes, and antioxidant contents of drought-stressed wheat plants as adaptive strategies. The results suggest that the expression of the studied genes (TaP5CS1, TaZFP34, TaWRKY1, TaMPK3, TaLEA, and the wheat housekeeping gene TaActin) in wheat remarkably enhanced wheat tolerance to drought stress. We discovered that the genes and metabolites involved significantly contributed to defense responses, making them potential targets for assessing drought tolerance levels. The drought tolerance indices of wheat were revealed by the mean productivity (MP), stress sensitivity index (SSI), yield stability index (YSI), and stress tolerance index (STI). We employed four databases, such as BAR, InterPro, phytozome, and the KEGG pathway, to predict and decipher the putative domains in prior gene sequencing. As a result, we discovered that these genes may be involved in a range of important biological functions in specific tissues at different developmental stages, including response to drought stress, proline accumulation, plant growth and development, and defense response. In conclusion, the sole and/or dual T. harzianum application to the wheat cultivar improved drought tolerance strength. These findings could be insightful data for wheat production in Saudi Arabia under various water regimes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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14. Modulating the conformation of microgels by complexation with inorganic nanoparticles.
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Vialetto, Jacopo, Ramakrishna, Shivaprakash N., Stock, Sebastian, von Klitzing, Regine, and Isa, Lucio
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POLYMER networks , *MICROGELS , *LIQUID-liquid interfaces , *NANOPARTICLES , *ATOMIC force microscopy , *SILICA nanoparticles , *NANOINDENTATION - Abstract
The complexation of microgels with rigid nanoparticles is an effective way to impart novel properties and functions to the resulting hybrid particles for applications such as in optics, catalysis, or for the stabilization of foams/emulsions. The nanoparticles affect the conformation of the polymer network, both in bulk aqueous environments and when the microgels are adsorbed at a fluid interface, in a non-trivial manner by modulating the microgel size, stiffness and apparent contact angle. Here, we provide a detailed investigation, using light scattering, in-situ atomic force microscopy and nano-indentation experiments, of the interaction between poly(N-isopropylacrylamide) microgels and hydrophobized silica nanoparticles after mixing in aqueous suspension to shed light on the network reorganization upon nanoparticle incorporation. The addition of nanoparticles decreases the microgels' bulk swelling and thermal response. When adsorbed at an oil-water interface, a higher ratio of nanoparticles influences the microgel's stiffness as well as their hydrophobic/hydrophilic character by increasing their effective contact angle, consequently modulating the monolayer response upon interfacial compression. Overall, these results provide fundamental understanding on the complex conformation of hybrid microgels in different environments and give inspiration to design new materials where the combination of a soft polymer network and nanoparticles might result in additional functionalities. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Size photometry and fluorescence imaging of immobilized immersed extracellular vesicles.
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Wallucks, Andreas, DeCorwin‐Martin, Philippe, Shen, Molly L., Ng, Andy, and Juncker, David
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EXTRACELLULAR vesicles , *IMAGE registration , *LED lighting , *SILICA nanoparticles , *MEMBRANE proteins - Abstract
Immunofluorescence analysis of individual extracellular vesicles (EVs) in common fluorescence microscopes is gaining popularity due to its accessibility and high fluorescence sensitivity; however, EV number and size are only measurable using fluorescent stains requiring extensive sample manipulations. Here we introduce highly sensitive label‐free EV size photometry (SP) based on interferometric scattering (iSCAT) imaging of immersed EVs immobilized on a glass coverslip. We implement SP on a common inverted epifluorescence microscope with LED illumination and a simple 50:50 beamsplitter, permitting seamless integration of SP with fluorescence imaging (SPFI). We present a high‐throughput SPFI workflow recording >10,000 EVs in 7 min over ten 88 × 88 µm2 fields of view, pre‐ and post‐incubation imaging to suppress background, along with automated image alignment, aberration correction, spot detection and EV sizing. We achieve an EV sizing range from 37 to ∼220 nm in diameter with a dual 440 and 740 nm SP illumination scheme, and suggest that this range can be extended by more advanced image analysis or additional hardware customization. We benchmark SP to flow cytometry using calibrated silica nanoparticles and demonstrate superior, label‐free sensitivity. We showcase SPFI's potential for EV analysis by experimentally distinguishing surface and volumetric EV dyes, observing the deformation of EVs adsorbed to a surface, and by uncovering distinct subpopulations in <100 nm‐in‐diameter EVs with fluorescently tagged membrane proteins. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Coprecipitation of amorphous silica and gold nanoparticles contributes to gold hyperenrichment.
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McNab, Rory R., Brugger, Joël, Voisey, Christopher R., and Tomkins, Andrew G.
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SILICA , *SILICA nanoparticles , *GOLD nanoparticles , *GOLD ores , *QUARTZ , *EARTHQUAKE aftershocks , *VEINS (Geology) - Abstract
Hyperenrichment of Au in orogenic ores occurs overwhelmingly within quartz veins, but the formation pathway of quartz veins in orogenic systems remains enigmatic. We conducted hydrothermal experiments simulating coprecipitation of Au and amorphous silica and subsequent recrystallization to test whether this is a viable mechanism to generate Au nuggets within quartz veins. Within minutes, coprecipitation of amorphous silica and Au nanoparticles occurred, representing an effective Au deposition mechanism. Within one week, amorphous silica had recrystallized to quartz, causing the coarsening of Au particles and their relocation to quartz grain boundaries and fractures. The experimental textures are similar to those observed in high-grade zones of orogenic gold deposits. In addition to trapping Au, amorphous silica may increase competency contrasts that facilitate short-term fracture reactivation during earthquake aftershock periods or swarms, allowing further Au input from fresh fluids. These findings demonstrate that amorphous silica precipitation may be an important transient stage in orogenic gold deposit formation, with significant implications for metal accumulation in quartz veins. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Adhesin Antibody-Grafted Mesoporous Silica Nanoparticles Suppress Immune Escape for Treatment of Fungal Systemic Infection.
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Cheng, Mengjuan, Liu, Suke, Zhu, Mengsen, Li, Mingchun, and Yu, Qilin
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SILICA nanoparticles , *MYCOSES , *CANDIDA albicans , *PHAGOCYTOSIS , *NANOPARTICLES - Abstract
Life-threatening systemic fungal infections caused by Candida albicans are significant contributors to clinical mortality, particularly among cancer patients and immunosuppressed individuals. The evasion of the immune response facilitated by fungal surface components enables fungal pathogens to evade macrophage attacks and to establish successful infections. This study developed a mesoporous silica nanoplatform, i.e., MSNP-EAP1Ab, which is composed of mesoporous silica nanoparticles grafted with the antibody of C. albicans surface adhesin Eap1. The activity of MSNP-EAP1Ab against C. albicans immune escape and infection was then evaluated by using the cell interaction model and the mouse systemic infection model. During interaction between C. albicans cells and macrophages, MSNP-EAP1Ab significantly inhibited fungal immune escape, leading to the enhanced phagocytosis of fungal cells by macrophages, with phagocytosis rates increasing from less than 8% to 14%. Furthermore, after treatment of the C. albicans-infected mice, MSNP-EAP1Ab drastically prolonged the mouse survival time and decreased the kidney fungal burden from >30,0000 CFU/g kidney to <100 CFU/g kidney, indicating the rapid recognition and killing of the pathogens by immune cells. Moreover, MSNP-EAP1Ab attenuated kidney tissue inflammation, with remarkable attenuation of renal immune cell accumulation. This study presents an innovative nanoplatform that targets the C. albicans adhesin, offering a promising approach for combatting systemic fungal infections. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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18. Mixed Systems of Quaternary Ammonium Foam Drainage Agent with Carbon Quantum Dots and Silica Nanoparticles for Improved Gas Field Performance.
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Sun, Yongqiang, Zhang, Yongping, Wei, Anqi, Shan, Xin, Liu, Qingwang, Fan, Zhenzhong, Sun, Ao, Zhu, Lin, and Kong, Lingjin
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SURFACE active agents , *SILICA nanoparticles , *GAS fields , *QUANTUM dots , *SURFACE tension , *FOAM - Abstract
Foam drainage agents enhance gas production by removing wellbore liquids. However, due to the ultra-high salinity environments of the Hechuan gas field (salinity up to 32.5 × 104 mg/L), no foam drainage agent is suitable for this gas field. To address this challenge, we developed a novel nanocomposite foam drainage system composed of quaternary ammonium and two types of nanoparticles. This work describes the design and synthesis of a quaternary ammonium foam drainage agent and nano-engineered stabilizers. Nonylphenol polyoxyethylene ether sulfosuccinate quaternary ammonium foam drainage agent was synthesized using maleic anhydride, sodium chloroacetate, N,N-dimethylpropylenediamine, etc., as precursors. We employed the Stöber method to create hydrophobic silica nanoparticles. Carbon quantum dots were then prepared and functionalized with dodecylamine. Finally, carbon quantum dots were incorporated into the mesopores of silica nanoparticles to enhance stability. Through optimization, the best performance was achieved with a (quaternary ammonium foam drainage agents)–(carbon quantum dots/silica nanoparticles) ratio of 5:1 and a total dosage of 1.1%. Under harsh conditions (salinity 35 × 104 mg/L, condensate oil 250 cm3/m3, temperature 80 °C), the system exhibited excellent stability with an initial foam height of 160 mm, remaining at 110 mm after 5 min. Additionally, it displayed good liquid-carrying capacity (160 mL), low surface tension (27.91 mN/m), and a long half-life (659 s). These results suggest the effectiveness of nanoparticle-enhanced foam drainage systems in overcoming high-salinity challenges. Previous foam drainage agents typically exhibited a salinity resistance of no more than 25 × 104 mg/L. In contrast, this innovative system demonstrates a superior salinity tolerance of up to 35 × 104 mg/L, addressing a significant gap in available agents for high-salinity gas fields. This paves the way for future development of advanced foam systems for gas well applications with high salinity. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Systematic Study of Reaction Conditions for Size-Controlled Synthesis of Silica Nanoparticles.
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Vörös-Horváth, Barbara, Salem, Ala', Kovács, Barna, Széchenyi, Aleksandar, and Pál, Szilárd
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SILICA nanoparticles , *NANOPARTICLE synthesis , *AMMONIUM hydroxide , *TEMPERATURE effect , *WATER temperature - Abstract
This study presents a reproducible and scalable method for synthesizing silica nanoparticles (SNPs) with controlled sizes below 200 nm, achieved by systematically varying three key reaction parameters: ammonium hydroxide concentration, water concentration, and temperature. SNPs with high monodispersity and controlled dimensions were produced by optimizing these factors. The results indicated a direct correlation between ammonium hydroxide concentration and particle size, while higher temperatures resulted in smaller particles with increased polydispersity. Water concentration also influenced particle size, with a quadratic relationship observed. This method provides a robust approach for tailoring SNP sizes, with significant implications for biomedical applications, particularly in drug delivery and diagnostics. Using eco-friendly solvents such as ethanol further enhances the sustainability and cost-effectiveness of the process. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Ethylene-Propylene-Methylene/Isoprene Rubber/SiO 2 Nanocomposites with Enhanced Mechanical Performances and Deformation Recovery Ability by a Combination of Synchronously Vulcanizing and Nanoparticle Reinforcement.
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Hu, Rongyan, Xiao, Ran, Xia, Xinxin, Shangguan, Yonggang, and Zheng, Qiang
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STRAIN hardening , *DICUMYL peroxide , *DEFORMATIONS (Mechanics) , *NANOPARTICLES , *SILICA nanoparticles - Abstract
It is highly desired yet challenging to develop advanced elastomers with excellent mechanical properties, including high strength and toughness. In this work, strong and tough rubber/rubber compound vulcanizates were facilely prepared by blending ethylene-propylene-methylene (EPM) and isoprene rubber (IR) together with dicumyl peroxide (DCP) and subsequent vulcanization, since both EPM and IR can be vulcanized synchronously by DCP and the well-crosslinked structure of EPM/IR vulcanizate presented a stable phase separation state. By tuning their composition, EPM/IR vulcanizates could present remarkably improved mechanical strength and toughness, as well as excellent energy dissipation and deformation recovery abilities. Furthermore, EPM/IR/SiO2 nanocomposites with better properties were prepared by introducing silica nanoparticles into EPM/IR vulcanizates. It was found that the high toughness and strength of EPM/IR vulcanizates and EPM/IR/SiO2 nanocomposites mainly resulted from the combination of stretchability of EPM and strain hardening of IR. Their excellent energy dissipation and deformation recovery abilities were related to the macromolecular characteristics of EPM and IR, compatibility between EPM and IR, and their crosslinking dynamics. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Preparation and Utilization of a Highly Discriminative Absorbent Imprinted with Fetal Hemoglobin.
- Author
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Zhang, Ka, Zhou, Tongchang, Dicko, Cedric, Ye, Lei, and Bülow, Leif
- Subjects
- *
OXYGEN carriers , *MOLECULAR imprinting , *EMULSION polymerization , *SILICA nanoparticles , *MOLECULAR recognition , *IMPRINTED polymers - Abstract
Development in hemoglobin-based oxygen carriers (HBOCs) that may be used as alternatives to donated blood requires an extensive supply of highly pure hemoglobin (Hb) preparations. Therefore, it is essential to fabricate inexpensive, stable and highly selective absorbents for Hb purification. Molecular imprinting is an attractive technology for preparing such materials for targeted molecular recognition and rapid separations. In this case study, we developed human fetal hemoglobin (HbF)-imprinted polymer beads through the fusion of surface imprinting and Pickering emulsion polymerization. HbF was firstly covalently coupled to silica nanoparticles through its surface-exposed amino groups. The particle-supported HbF molecules were subsequently employed as templates for the synthesis of molecularly imprinted polymers (MIPs) with high selectivity for Hb. After removing the silica support and HbF, the resulting MIPs underwent equilibrium and kinetic binding experiments with both adult Hb (HbA) and HbF. These surface-imprinted MIPs exhibited excellent selectivity for both HbA and HbF, facilitating the one-step isolation of recombinant Hb from crude biological samples. The saturation capacities of HbA and HbF were found to be 15.4 and 17.1 mg/g polymer, respectively. The present study opens new possibilities for designed resins for tailored protein purification, separation and analysis. [ABSTRACT FROM AUTHOR]
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- 2024
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22. Dual Fractions Proteomic Analysis of Silica Nanoparticle Interactions with Protein Extracts.
- Author
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Schvartz, Marion, Saudrais, Florent, Boulard, Yves, Renault, Jean-Philippe, Henry, Céline, Chédin, Stéphane, Pin, Serge, and Aude, Jean-Christophe
- Subjects
- *
SILICA nanoparticles , *SILICA analysis , *NANOPARTICLES , *SACCHAROMYCES cerevisiae , *MASS spectrometry - Abstract
Dual-fraction proteomics reveals a novel class of proteins impacted by nanoparticle exposure. Background: Nanoparticles (NPs) interact with cellular proteomes, altering biological processes. Understanding these interactions requires comprehensive analyses beyond solely characterizing the NP corona. Methods: We utilized a dual-fraction mass spectrometry (MS) approach to analyze both NP-bound and unbound proteins in Saccharomyces cerevisiae sp. protein extracts exposed to silica nanoparticles (SiNPs). We identified unique protein signatures for each fraction and quantified protein abundance changes using spectral counts. Results: Strong correlations were observed between protein profiles in each fraction and non-exposed controls, while minimal correlation existed between the fractions themselves. Linear models demonstrated equal contributions from both fractions in predicting control sample abundance. Combining both fractions revealed a larger proteomic response to SiNP exposure compared to single-fraction analysis. We identified 302/56 proteins bound/unbound to SiNPs and an additional 196 "impacted" proteins demonstrably affected by SiNPs. Conclusion: This dual-fraction MS approach provides a more comprehensive understanding of nanoparticle interactions with cellular proteomes. It reveals a novel class of "impacted" proteins, potentially undergoing conformational changes or aggregation due to NP exposure. Further research is needed to elucidate their biological functions and the mechanisms underlying their impact. [ABSTRACT FROM AUTHOR]
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- 2024
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23. Self-propelled enzyme-controlled IR-mesoporous silica Janus nanomotor for smart delivery.
- Author
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Mayol, Beatriz, Pradana-López, Sandra, García, Alba, de la Torre, Cristina, Díez, Paula, Villalonga, Anabel, Anillo, Carlos, Vilela, Diana, Sánchez, Alfredo, Martínez-Ruiz, Paloma, Martínez-Máñez, Ramón, and Villalonga, Reynaldo
- Subjects
- *
SILICA nanoparticles , *NANOPARTICLES , *GLUCONIC acid , *GLUCOSE oxidase , *BORONIC esters , *MESOPOROUS silica - Abstract
[Display omitted] Here, we report the preparation of a novel Janus nanoparticle with opposite Ir and mesoporous silica nanoparticles through a partial surface masking with toposelective modification method. This nanomaterial was employed to construct an enzyme-powered nanomachine with self-propulsion properties for on-command delivery. The cargo-loaded nanoparticle was provided with a pH-sensitive gate and unit control at the mesoporous face by first attaching boronic acid residues and further immobilization of glucose oxidase through reversible boronic acid esters with the carbohydrate residues of the glycoenzyme. Addition of glucose leads to the enzymatic production of H 2 O 2 and gluconic acid, being the first compound catalytically decomposed at the Ir nanoparticle face producing O 2 and causing the nanomachine propulsion. Gluconic acid leads to a pH reduction at the nanomachine microenvironment causing the disruption of the gating mechanism with the subsequent cargo release. This work demonstrates that enzyme-mediated self-propulsion improved release efficiency being this nanomotor successfully employed for the smart release of Doxorubicin in HeLa cancer cells. [ABSTRACT FROM AUTHOR]
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- 2024
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24. Structure and Potential Application of Surfactant-Free Microemulsion Consisting of Heptanol, Ethanol and Water.
- Author
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Gudelj, Martina, Kranjac, Marina, Jurko, Lucija, Tomšič, Matija, Cerar, Janez, Prkić, Ante, and Bošković, Perica
- Subjects
ELECTRICAL conductivity measurement ,FOURIER transform infrared spectroscopy ,SURFACE tension ,TRANSMISSION electron microscopy ,SILICA nanoparticles - Abstract
Microemulsions, which are thermodynamically stable and isotropic mixtures of water, oil, and surfactants, attract significant research interest due to their unique physicochemical properties and diverse industrial applications. Traditional surfactant-based microemulsions (SBMEs) stabilize the interface between two typically immiscible liquids, forming various microstructures such as oil-in-water (O/W) droplets, water-in-oil (W/O) droplets, and bicontinuous phases. However, the use of surfactants poses environmental concerns, cost implications, and potential toxicity. Consequently, there is increasing interest in developing surfactant-free microemulsions (SFMEs) that offer similar benefits without the drawbacks associated with surfactants. In this study, we explore the formation and characteristics of a new surfactant-free microemulsion in a ternary system comprising water, ethanol, and heptanol. Advanced techniques are employed to characterize the microstructures and stability of surfactant-free microemulsions. These include electrical conductivity measurements, surface tension analysis, dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FTIR). These methods have been extensively used in previous research on surfactant-free microemulsions (SFMEs) to reveal the properties and interactions within microemulsion systems. The area of interest is identified using these techniques, where silica nanoparticles are subsequently synthesized and then visualized using transmission electron microscopy (TEM). [ABSTRACT FROM AUTHOR]
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- 2024
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25. Supramolecular self‐assembled nanoparticles for targeted therapy of myocardial infarction by enhancing cardiomyocyte mitophagy.
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Jiao, Yang, Wang, Haimang, Weng, Xiechuan, Wang, Jihang, Li, Ying, Shen, Jian, Zhao, Weiwei, Xi, Qing, Zhang, Hongyu, and Fu, Zhenhong
- Subjects
MYOCARDIAL infarction ,SILICA nanoparticles ,CORONARY disease ,MESOPOROUS silica ,INTRAVENOUS injections - Abstract
Myocardial infarction accompanied by diabetes mellitus is accepted as the most serious type of coronary heart disease, and among the current treatment strategies, the precise delivery of protective drugs for inhibiting cardiomyocyte apoptosis is still a challenge. In this study, we developed a biodegradable nanoparticles‐based delivery system with excellent macrophage escape, cardiac targeting, and drug release properties to achieve targeted therapy of myocardial infarction. Specifically, a copolymer of p(DMA–MPC–CD) combining self‐adhesion, hydration lubrication, and targeting peptide binding site was successfully prepared by free radical copolymerization, and it was self‐assembled on the surface of melatonin‐loaded dendritic mesoporous silica nanoparticles (bMSNs) following the integration of adamantane‐modified cardiac homing peptide (CHP) based on supramolecular host–guest interaction. Importantly, a hydration layer formed around the zwitterionic phosphorylcholine groups of the multifunctional nanoparticles, which was confirmed by the enhancement in hydration lubrication and reduction in coefficient of friction, prevented the nanoparticles from phagocytosis by the macrophages. The in vivo bioluminescence imaging test indicated that the nanoparticles were endowed with satisfied cardiac targeting capability, and the in vivo mice study demonstrated that the intravenous injection of drug‐loaded nanoparticles (namely bMSNs–Mel@PDMC–CHP) effectively reduced cardiomyocyte apoptosis, alleviated myocardial interstitial fibrosis, and enhanced cardiac function. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
- View/download PDF
26. Synthesis of acrylate copolymer‐based super oil adsorption resins and their performances.
- Author
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Zhou, Feng, Song, Yu, Li, Yu, and Ren, Xianyan
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ADSORPTION kinetics ,ADSORPTION capacity ,DIESEL fuels ,SILICA nanoparticles ,OIL spills - Abstract
In this paper, an acrylate copolymer‐based oil adsorption resin was designed and synthesized by a suspension polymerization with octadecyl acrylate (SA) and butyl acrylate (BA) as monomers, divinylbenzene (DVB) as a cross‐linking agent, and toluene as a pore‐forming agent. By studying the synthesis conditions, the copolymer "SA‐BA‐DVB" (PSBA) with the best adsorption capacity was obtained, when the molar ratio between SA and BA was about 0.9, the content of the DVB and PVA 1788 was about 0.107 wt% and 1.0 wt%, respectively, accounting for the total mass amount of the monomers. Furthermore, by introducing 2% reactive silica nanoparticles (R‐SiO2), the performances of the PSBA were improved due to its increased hydrophobicity and activity space. The equilibrium adsorption capacity of the resulted R‐SiO2/PSBA to kerosene, diesel oil, benzene, and p‐xylene was 31.90, 34.13, 39.44, and 41.81 mL/g, respectively, which is about 1.12 to 1.21 times higher than that of the PSBA. Also, the R‐SiO2/PSBA show brilliant oil retention rate of about 99% after centrifugation at 3000 rpm for 5 min and recycling ability which can be reusable for at least 10 absorption‐desorption cycles without capacity change, demonstrating that the obtained R‐SiO2/PSBA resin can be used as oil removing agents in the field of oil spill applications. Highlights: R‐SiO2 modified acrylate copolymer as an oil adsorption resin was designed and synthesized.The influence of the monomers, cross‐linking agent, and others on the adsorption resin was systematically studied.The adsorption kinetics and performances of the adsorption resin were studied. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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27. Reactivity of a plagioclase concentrate from the South African Bushveld Igneous Complex via extractive acid leaching vs. extractive roasting-leaching processes.
- Author
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Mohamed, Sameera, van der Merwe, Elizabet M., Nkosi, Zakhele H., Altermann, Wladyslaw, Grote, Wiebke, and Doucet, Frédéric J.
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AMMONIUM sulfate ,CALCIUM aluminate ,SILICA nanoparticles ,PLAGIOCLASE ,ORTHOPYROXENE - Abstract
This study compared the reactivity of a plagioclase concentrate subjected to two processes: (1) direct acid leaching and (2) thermochemical treatment with ammonium sulfate followed by leaching. The sample was prepared from coarse-grained pyroxenite rock retrieved from the Bushveld Igneous Complex, South Africa. It contained 78% plagioclase (labradorite), 9% orthopyroxene (enstatite) and 13% quartz. The elements contained in the concentrate were categorized into three groups based on their susceptibility to direct acid extraction after 6 h of leaching. Group 1 consisted of the highly reactive main elements of plagioclase (Al, Ca and Na, with extraction efficiencies of 95%, 89% and 81%, respectively). Group 2 included elements predominantly present in enstatite (Mg and Fe with extraction efficiencies of 41% and 55%, respectively). Group 3 was composed of slowly extractable Si (25%) from mostly plagioclase. Increasing the duration of direct acid leaching to 24 h had no effect on the extraction of Group 1 elements, whereas the extraction of Mg and Fe (Group 2) increased to >60%, and that of Si (Group 3) increased from 25 to 80%. The latter correlated with the nearly complete disappearance of the plagioclase blueprint in the XRD pattern of the residues generated after 24 h of leaching. In contrast, plagioclase had limited reactivity with ammonium sulfate during thermochemical treatment. Direct acid leaching of plagioclase-rich tailings can therefore generate leachates to be used as precursors for the preparation of value-added products, such as silica nanoparticles via a sol–gel route and calcium aluminate nanoparticles via solution combustion. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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28. Rod-shaped mesoporous silica nanoparticles reduce bufalin cardiotoxicity and inhibit colon cancer by blocking lipophagy.
- Author
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Fan, Yibao, Zhang, Wei, Iqbal, Zoya, Li, Xinxin, Lin, Zhiyin, Wu, Zhuolin, Li, Qianyou, Dong, Hongxia, Zhang, Xianbin, Gong, Peng, and Liu, Peng
- Subjects
- *
STAINS & staining (Microscopy) , *TARGETED drug delivery , *COLON cancer , *SILICA nanoparticles , *CANCER cell growth - Abstract
Background: Bufalin (BA) is a potent traditional Chinese medicine derived from toad venom. It has shown significant antitumor activity, but its use is limited by cardiotoxicity, which necessitates innovative delivery methods, such as rod-shaped mesoporous silica nanoparticles (rMSNs). rMSNs have been extensively employed for reducing drug toxicity and for controlled or targeted drug delivery in tumor therapy. However, their potential in delivering BA has not been completely elucidated. Therefore, in this study, BA-loaded rMSNs (BA-rMSNs) were developed to investigate their potential and mechanism in impairing colon cancer cells. Methods: rMSNs were developed via the sol‒gel method. Drug encapsulation efficiency and loading capacity were determined to investigate the advantages of the rMSN in loading BA. The antiproliferative activities of the BA-rMSNs were investigated via 5-ethynyl-2'-deoxyuridine and CCK-8. To evaluate cell death, Annexin V-APC/PI apoptotic and calcein-AM/PI double staining were performed. Western blotting, oil red O staining, and Nile red solution were employed to determine the ability of BA-rMSNs to regulate lipophagy. Results: The diameter of the BA-rMSNs was approximately 60 nm. In vitro studies demonstrated that BA-rMSNs markedly inhibited HCT 116 and HT-29 cell proliferation and induced cell death. In vivo studies revealed that BA-rMSNs reduced BA-mediated cardiotoxicity and enhanced BA tumor targeting. Mechanistic studies revealed that BA-rMSNs blocked lipophagy. Conclusions: rMSNs reduced BA-mediated cardiotoxicity and impaired the growth of colon cancer cells. Mechanistically, antitumor activity depends on lipophagy. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
- View/download PDF
29. Highly stable double-emission long afterglow phosphor for dynamic anti-counterfeiting.
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Li, Weiwei, Yuan, Xiang, Feng, Lijuan, and Jiang, Guiquan
- Subjects
- *
LIGHT sources , *TECHNOLOGICAL innovations , *SILICA nanoparticles , *MESOPOROUS silica , *SILICA - Abstract
A highly stable single-excitation double-emission long afterglow phosphor is reported for use in dynamic anti-counterfeiting. The red phosphor ZnCaGa2O4:Cr3+ was introduced into the pores of mesoporous silica nanoparticles (MSNs) by in situ polymerization, and the green phosphor SrAl2O4:Eu2+,Dy3+, when embedded in silicon dioxide, provided a long-lasting waterproof afterglow. The anti-counterfeiting material emits red light under UV excitation at 254 nm and, on stopping the excitation, produces a long-lasting green afterglow. Traditional anti-counterfeiting methods often require the use of a variety of different excitation light sources to achieve different luminous effects, while this innovative material requires only one excitation light source to achieve red light and green afterglow, and greatly simplifies the preparation process of anti-counterfeiting materials. In addition, this material is highly stable and can maintain its luminescent properties for a long time under various environmental conditions and is not prone to fading or degradation. Single-excitation dual-emission long afterglow anti-counterfeiting materials can effectively prevent products from being counterfeited, and this study provides new ideas and methods for technological innovation in the field of anti-counterfeiting. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. A Single‐Dose mRNA Vaccine Employing Porous Silica Nanoparticles Induces Robust Immune Responses Against the Zika Virus.
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Shin, Hojeong, Kang, Seounghun, Won, Cheolhee, and Min, Dal‐Hee
- Subjects
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POROUS silica , *SILICA nanoparticles , *ZIKA virus , *VIRAL vaccines , *GENETIC translation - Abstract
Recently, lipid nanoparticles (LNPs)‐based mRNA delivery has been approved by the FDA for SARS‐CoV‐2 vaccines. However, there are still considerable points for improvement in LNPs. Especially, local administration of LNPs‐formulated mRNA can cause off‐target translation of mRNA in distal organs which can induce unintended adverse effects. With the hypothesis that large and rigid nanoparticles can be applied to enhance retention of nanoparticles at the injection site, a polyethyleneimine (PEI)‐coated porous silica nanoparticles (PPSNs)‐based mRNA delivery platform is designed. PPSNs not only facilitate localized translation of mRNA at the site of injection but also prolonged protein expression. It is further demonstrated that the development of a highly efficacious Zika virus (ZIKV) vaccine using mRNA encoding full‐length ZIKV pre‐membrane (prM) and envelope (E) protein delivered by PPSNs. The ZIKV prME mRNA‐loaded PPSNs vaccine elicits robust immune responses, including high levels of neutralizing antibodies and ZIKV E‐specific T cell responses in C57BL/6 mice. Moreover, a single injection of prME‐PPSNs vaccine provided complete protection against the ZIKV challenge in mice. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Development of Ce/Cu co-doped dendritic mesoporous silica nanoparticles (DMSNs) as novel abrasive systems toward high-performance chemical mechanical polishing.
- Author
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Zhou, Wenjin, Chen, Yang, Wang, Chao, Wang, Menghan, and Chen, Ailian
- Subjects
- *
MESOPOROUS silica , *COPPER , *SILICA nanoparticles , *GRINDING & polishing , *DOPING agents (Chemistry) , *PHOTOCATALYSIS , *ABRASIVES , *X-ray emission spectroscopy , *CHEMILUMINESCENCE assay - Abstract
Development of novel abrasive systems with functional activities and physicochemical properties are of great significance in the reactive oxygen species (ROS)-enhanced chemical mechanical polishing. In this work, Ce single-doped and Ce/Cu co-doped dendritic mesoporous silica nanoparticles (DMSNs), namely Ce−DMSNs and Ce/Cu−DMSNs, were produced via a simple impregnation and thermolysis procedure. The Ce and/or Cu species involved in DMSNs frameworks were characterized through X-ray diffractometry, infrared spectroscopy, scanning electron microscopy, energy dispersive spectrometry, transmission electron microscopy, X-ray photoelectron spectroscopy, and nitrogen adsorption/desorption techniques. We report the evolution of surface morphology and roughness, defects, peak-to-valley data, image surface area difference, and material removal efficiency during ROS-enhanced polishing experiments toward silica materials. All the pure, Ce single-doped, and Ce/Cu co-doped DMSNs abrasive systems offered nearly defect-free surfaces with close-to-atom scale roughness. It might be attributed to the "springlike effect" and "soft polishing/abrasion", possibly originating from the low-modulus DMSNs carriers. Among these abrasives, the Ce/Cu co-doped DMSNs systems achieved an evident improvement in removal efficiency, especially under ultraviolet irradiation-assisted polishing conditions. The coexisted Ce(Ⅲ)/Ce(Ⅳ) and Cu(Ⅰ)/Cu(Ⅱ) couples might be responsible for the effective production of ROS in photocatalysis and Fenton-like processes, thereby contributing to the Si–OH and Ce(Ⅲ)−O–Si bonding formations. The role of the developed Ce/Cu co-doped DMSNs abrasive systems in ROS-enhanced polishing processes was discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. Preparation of hyperbranched hydrophobic nano-silica and its superior needling-effect in PDMS defoam agent.
- Author
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Wang, Linan, Wang, Huanmin, Rong, Mingming, Li, Wei, Li, Ning, Liu, Peisong, Li, Xiaohong, and Zhang, Zhijun
- Subjects
- *
STERIC hindrance , *SILICON surfaces , *HYDROXYL group , *SURFACE properties , *SILICA , *SILICA nanoparticles - Abstract
[Display omitted] • Silica with hydrophobic hyperbranched structure was obtained. • Excellent defoaming and antifoaming effects were obtained in PDMS. • Hyperbranched microstructure exhibit superior "needle effect". • The "interface − coordination" defoaming mechanism is proposed. Hydrophobic nano silica powder is a kind of important synergist to silicone defoaming agents. The large pore volume and branched chain conformation of silica nanoparticles present superior effects on defoaming properties. However, silica nanoparticles synthesized by liquid phase easily aggregate and pore collapse because of their high surface activity and polarity, leading to poorer dispersity and limited practicability. In this paper, a novel hydrophobic silica with a hyperbranched structure was designed through in-situ modifying method with hexamethyldisilazane (HMDS) and polydimethylsiloxane (PDMS) in the liquid phase. The trimethylsilanol generated by HMDS hydrolysis reacts quickly with the highly active hydroxyl groups on the silica, causing the surface properties of the nanoparticles to transform from polar to non-polar properties. The steric hindrance of the trimethyl silicon and the reduction of the surface polarity effectively prevent silica pores from collapsing and maintain the macropore structures to realize the hyperbranched silica. At the same time, the −Si (CH 3) 2 − from PDMS endowed the hyperbranched silica with excellent hydrophobicity. When applied in the defoaming agent, the hydrophobicity of silica contributes to dewetting the foams, and the hyperbranched spatial structures play an enhanced needling effect. Therefore, this hydrophobic hyperbranched silica exhibited a surprising defoaming effect, which significantly reduced the defoaming time from 464.4 s to less than 2 s, superior to commercial defoaming silica (155.3 s). The defoaming efficiency reached 100 % within 2 s of the end of the shaking, and the defoamer antifoaming ability was improved to reach 27.5 min, which was 77 % higher than that of commercial defoamer. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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33. Polycarbosilane-grafted silicon carbide nanoparticles as a high-yielding non-oxide ceramic precursor.
- Author
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Posey, Nicholas D., Pruyn, Timothy L., Delcamp, Jared H., and Dickerson, Matthew B.
- Subjects
- *
SILICON carbide , *SURFACE grafting (Polymer chemistry) , *NANOPARTICLES , *SILICA nanoparticles , *CERAMICS , *GRAFT copolymers , *CERAMIC coating , *SLURRY - Abstract
Silicon carbide (SiC) is a multifunctional material with a myriad of potential applications, from high-power electronics to friction applications to power generation. Grafting preceramic polymers (PCPs) from SiC nanoparticles would create a platform for forming SiC via a polymer derived route that would have advantages over simple particle-PCP slurries and may enable new additive manufacturing inks or spreadable coatings with controlled rheology. Grafting PCPs directly on SiC powders would greatly improve dispersion of these particles and yield a single component system. Moreover, PCP-grafted-SiC would be a new addition to the burgeoning field of polymer grafted nanoparticles (PGNPs). Herein, SiC nanoparticles were surface-modified in a grafting-from polymerization reaction to create polycarbosilane (PCS) grafted SiC. Surface grafting was verified through a number of analytical techniques and the synthesized materials were pyrolyzed at 1600 °C. The PCS-grafted SiC retained 66 % of its pre-pyrolysis mass, representing a significant improvement over PCS-grafted silica nanoparticles from our previous work (20 wt% yield). In addition to an increased ceramic yield, the grafting of PCS to SiC also resulted in the formation of a SiC phase not present in the simple physical mixture of SiC nanopowder in PCS. This study demonstrated that PCP-grafted nanoparticles (GNPs) can be synthesized utilizing non-oxide nanoparticle cores with desirable rheology, opening possibilities for future ceramic inks and coatings. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
- View/download PDF
34. Advances in Immunomodulatory Mesoporous Silica Nanoparticles for Inflammatory and Cancer Therapies.
- Author
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Gu, Bin, Zhao, Qin, and Ao, Yiran
- Subjects
- *
SILICA nanoparticles , *ANTIGEN presentation , *DRUG delivery systems , *CLINICAL medicine , *IMMUNE response , *MESOPOROUS silica - Abstract
In recent decades, immunotherapy has been considered a promising treatment approach. The modulatable enhancement or attenuation of the body's immune response can effectively suppress tumors. However, challenges persist in clinical applications due to the lack of precision in antigen presentation to immune cells, immune escape mechanisms, and immunotherapy-mediated side effects. As a potential delivery system for drugs and immunomodulators, mesoporous silica has attracted extensive attention recently. Mesoporous silica nanoparticles (MSNs) possess high porosity, a large specific surface area, excellent biocompatibility, and facile surface modifiability, making them suitable as multifunctional carriers in immunotherapy. This article summarizes the latest advancements in the application of MSNs as carriers in cancer immunotherapy, aiming to stimulate further exploration of the immunomodulatory mechanisms and the development of immunotherapeutics based on MSNs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. PBAT/PLA-Based Electrospun Nanofibrous Protective Clothes with Superhydrophobicity, Permeability, and Thermal Insulation Characteristics for Individuals with Disabilities.
- Author
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Aijaz, Muhammad Omer, Abdus Samad, Ubair, Alnaser, Ibrahim A., Siddiqui, Md Irfanul Haque, Assaifan, Abdulaziz K., and Karim, Mohammad Rezaul
- Subjects
- *
PROTECTIVE clothing , *OUTDOOR clothing , *INFRARED photography , *SILICA nanoparticles , *PADS & protectors (Textiles) - Abstract
This study presents the development of multifunctional protective clothing for disabled individuals using PBAT/PLA biopolymeric-based electrospun nanofibrous membranes. The fabric consists of a superhydrophobic electrospun nanofibrous cloth reinforced with silica nanoparticles. The resulting nanofiber membranes were characterized using FE-SEM, a CA goniometer, breathability and hydrostatic pressure resistance tests, UV–vis spectroscopy, thermal infrared photography, tensile tests, and nanoindentation. The results demonstrated the integration of superhydrophobicity, breathability, and mechanical improvements in the protective clothing. The nanofibrous porous structure of the fabric allowed breathability, while the silica nanoparticles acted as an effective infrared reflector to keep the wearer cool on hot days. The fabric's multifunctional properties make it suitable for various products, such as outdoor clothing and accessories for individuals with disabilities. This study highlights the importance of selecting appropriate textiles for protective clothing and the challenges faced by disabled individuals in terms of mobility, eating, and dressing. The innovative and purposeful design of this multifunctional protective clothing aimed to enrich the lives of individuals with disabilities. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Improvement the physicochemical properties of cation exchange membranes by incorporation SiO2-co-Ag nanoparticles.
- Author
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Ghazanfarpour, Somayeh, Ghazanfarpour, Samaneh, Azarnik, Maryam, Zendehnam, Akbar, and Hosseini, Seyyed Mohsen
- Subjects
- *
ION-permeable membranes , *ESCHERICHIA coli , *SILICA nanoparticles , *ATOMIC force microscopy , *SCANNING electron microscopy - Abstract
Ion exchange membranes were fabricated using a phase inversion technique based on polyvinyl chloride nanocomposites. Subsequently, electrodialysis membranes were modified by the addition of [SiO2-co-Ag] nanoparticles using magnetron sputtering. The impact of varying concentrations of [SiO2-co-Ag] nanoparticles on the performance of mixed-matrix poly (vinyl chloride)-based nanoparticle cation exchange membranes was studied. Various techniques, including scanning electron microscopy (SEM), atomic force microscopy (AFM), and scanning optical microscopy (SOM) confirmed the presence of nanoparticles in the structure of membranes. The SEM images showed that the addition of SiO2-co-Ag nanoparticles resulted in a more compact structure for the modified membranes. The SOM images show that the fabricated membranes had a uniform surface and uniform distribution of SiO2-Ag in the membrane matrix. The AFM images revealed that the modified membranes had a rough surface at high additive concentrations (4.0% wt.) and cross-sectional SEM images confirmed that the addition of nanoparticles created cracks and cavities in the membrane structure. The hydrophilicity of silica and silver nanoparticles increased the surface hydrophilicity of the modified membranes. The membrane potential, permselectivity, and transport number showed fluctuations, decreasing initially with the use of SiO2-co-Ag nanoparticles up to a concentration of 1.0% wt and then increasing with an increase in the concentration of nanoparticles to 2.0% wt before declining again for a concentration of 4.0% wt. The flux and ionic permeability were promoted by the addition of SiO2-co-Ag up to 1.0% wt, but after that, they showed a decreasing trend with an increase in the concentration of nanoparticles. The areal electrical resistance of the prepared membrane dramatically declined with an increase in the concentration of SiO2-Ag. Importantly, the application of these membranes was in electrodialysis, and the use of also enhanced the mechanical resistance of the membranes. Furthermore, the fabricated membranes exhibited a good ability to remove E. coli from water. Notably, the modified membrane with a 1.0% wt concentration of SiO2-co-Ag nanoparticles demonstrated greater performance in removing E. coli. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
37. Induction of antigen-specific immunity by mesoporous silica nanoparticles incorporating antigen peptides.
- Author
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Goto, Koichi, Ueno, Tomoya, and Sakaue, Saki
- Subjects
- *
CYTOTOXIC T cells , *MESOPOROUS silica , *DRUG delivery systems , *SILICA nanoparticles , *IMMUNOGLOBULIN G , *T cells - Abstract
Mesoporous silica nanoparticles (MSNs) are physically and chemically stable inorganic nanomaterials that have been attracting much attention as carriers for drug delivery systems in the field of nanomedicine. In the present study, we investigated the potential of MSN vaccines that incorporate antigen peptides for use in cancer immunotherapy. In vitro experiments demonstrated that fluorescently labeled MSNs accumulated in a line of mouse dendritic cells (DC2.4 cells), where the particles localized to the cytosol. These observations could suggest that MSNs have potential for use in delivering the loaded molecules into antigen-presenting cells, thereby stimulating the host acquired immune system. In vivo experiments demonstrated prolonged survival in mice implanted with ovalbumin (OVA)-expressing lymphoma cells (E.G7-OVA cells) following subcutaneous inoculation with MSNs incorporating OVA antigen peptides. Furthermore, OVA-specific immunoglobulin G antibodies and cytotoxic T lymphocytes were detected in the serum and the spleen cells, respectively, of mice inoculated with an MSN-OVA vaccine, indicating the induction of antigen-specific responses in both the humoral and cellular immune systems. These results suggested that the MSN therapies incorporating antigen peptides may serve as novel vaccines for cancer immunotherapy. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. Ciprofloxacin Metal Complexes–Silica Nanoparticles: Characterization, Spectroscopic Study, DNA Interaction and Biological Activity.
- Author
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Abd El-Zahir, Mustafa S., Saleh, Sayed M., ElKady, Hamdy A., and Orabi, Adel S.
- Subjects
- *
DRUG delivery systems , *SILICA nanoparticles , *ELECTRONIC spectra , *METAL nanoparticles , *COPPER , *CIPROFLOXACIN - Abstract
Ciprofloxacin (CIPH) was classified as one of the most effective quinolone antibiotics, which is commonly used to cure a wide range of infections resulting from Gram-negative and Gram-positive microorganisms. The complexes which formed due to the interaction of Ni(II), Zn(II), Cu(II), Gd(III) and Sm(III) with ciprofloxacin were characterized by CHN% analysis, conductivity, FTIR, electronic spectra, fluorescence measurements, and magnetic susceptibility, besides studying the complex–DNA interaction. Meanwhile, the molar conductance values (0.001 mol·L−1 in DMSO) revealed the electrolytic behavior of the complexes and could be designated with the A−B+ formula. In addition, the geometry of the compounds was confirmed from the electronic transitions as well as the μeff values as octahedral for all complexes. The postulated formula could be generally assigned as [M(CIP)a(CIPH)b(H2O)c](NO3)(H2O)n(C2H5OH)m. Moreover, the interaction between metal complexes and DNA revealed that the Cu complex had the highest binding constant. Nanotechnology was applied to synthesized compounds using silica nanoparticles (SiNPs), which were prepared using a sol–gel process. The silica nanoparticles were chemically functionalized for binding the ligand and its metal complexes; this enables the as-prepared compounds to enhance their features as a drug delivery platform. Meanwhile, the antimicrobial activity was tested for the free complexes and SiNPs composites. Collectively, Sm complex gave the largest zone of inhibition, while the Cu(II)–SiNPs composite showed the strongest potential to reduce the bacterial activity. Furthermore, the fluorescence data of CIPH, ligand–metal mixture and the effect of silica nanoparticles on them were studied. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. Effect of Silica Nanoparticle Treatment on Adhesion between Tissue-like Substrates and In Vivo Skin Wound Sealing.
- Author
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Jeon, Yeji, Kim, Tae Ryeol, Park, Eun Seo, Park, Jae Hyun, Youn, Han Sung, Hwang, Dae Youn, and Seo, Sungbaek
- Subjects
CONNECTIVE tissue growth factor ,SILICA nanoparticles ,TISSUE adhesions ,VASCULAR endothelial growth factors ,CHEMICAL reactions - Abstract
Silica nanoparticles are innovative solutions of surgical glue that can readily adhere to various tissue-like substrates without the need for time-consuming chemical reactions or ultraviolet irradiation. Herein, 10 nm-sized silica nanoparticle (SiNP
10 ) treatment exhibited maximum adhesion strength in the porcine heart tissue model, which was approximately 7.15 times higher than that of the control group of non-treatment. We assessed the effects of silica nanoparticle treatment on in vivo skin wounds by scoring tissue adhesion and inflammation using histological images. Compared to the commercial cyanoacrylate skin adhesive (Dermabond), suppression of inflammatory cytokine levels in the incision wound skin was observed. We further quantified the expression of angiogenic growth factors and connective tissue formation-related proteins. On day 5 after wound closing treatment, the expression levels of PDGF-BB growth factor were significantly higher in SiNP10 treatment (0.64 ± 0.03) compared to Dermabond (0.07 ± 0.05). This stimulated angiogenesis and connective tissue formation in the skin of the incision wound may be associated with the promoting effects of SiNP10 treatment on wound closure and tissue adhesion. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
40. Application of Silica Nanoparticles Improved the Growth, Yield, and Grain Quality of Two Salt-Tolerant Rice Varieties under Saline Irrigation.
- Author
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Jin, Wenyu, Li, Lin, He, Wenli, and Wei, Zhongwei
- Subjects
LEAF area index ,SALINE irrigation ,SILICA nanoparticles ,SOLUTION (Chemistry) ,RICE quality - Abstract
Salt stress significantly reduces rice yield and quality and is a global challenge, especially in arid and semi-arid regions with limited freshwater resources. The present study was therefore conducted to examine the potential of silica nanoparticles (SiO
2 NPs) in mitigating the adverse effects of saline irrigation water in salt-tolerant rice. Two salt-tolerant rice varieties, i.e., Y liangyou 957 (YLY957) and Jingliangyou 534 (JLY534), were irrigated with 0.6% salt solution to simulate high-salt stress and two SiO2 NPs were applied, i.e., control (CK) and SiO2 NPs (15 kg hm−2 ). The results demonstrated that the application of SiO2 NPs increased, by 33.3% and 23.3%, the yield of YLY957 and JLY534, respectively, compared with CK, which was primarily attributed to an increase in the number of grains per panicle and the grain-filling rate. Furthermore, the application of SiO2 NPs resulted in a notable enhancement in the chlorophyll content, leaf area index, and dry matter accumulation, accompanied by a pronounced stimulation of root system growth and development. Additionally, the SiO2 NPs also improved the antioxidant enzyme activities, i.e., superoxide dismutase, peroxidase, and catalase activity and reduced the malondialdehyde content. The SiO2 NPs treatment effectively improved the processing quality, appearance quality, and taste quality of the rice. Furthermore, the SiO2 NPs resulted in improvements to the rapid viscosity analyzer (RVA) pasting profile, including an increase in peak viscosity and breakdown values and a reduction in setback viscosity. The application of SiO2 NPs also resulted in a reduction in crystallinity and pasting temperature owing to a reduction in the proportion of B2 + B3 amylopectin chains. Overall, the application of silica nanoparticles improved the quality of rice yield under high-salt stress. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
41. The Effects of Different Blending Methods on the Thermal, Mechanical, and Optical Properties of PMMA/SiO 2 Composites.
- Author
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Lin, Chi-Kai, Xie, Jia-Wei, Tsai, Ping-Jui, Wang, Hao-Yu, Lu, Zhi-Wei, Lin, Tung-Yi, and Kuo, Chih-Yu
- Subjects
GLASS transition temperature ,SILICA nanoparticles ,DOUBLE bonds ,INSULATING materials ,SCANNING electron microscopy - Abstract
In this study, PMMA/SiO
2 composites were fabricated with monodispersed SiO2 and PMMA using four distinct methods—physical blending, in situ polymerization, random copolymerization, and block copolymerization—to investigate the composites' thermal, mechanical, and optical properties. In the physical blending approach, SiO2 nanoparticles were dispersed in a PMMA solution, while during in situ polymerization, silica nanoparticles were incorporated during the synthesis of PMMA/SiO2 composites. 3-methacryloxypropyltrimethoxysilane (MPS) was modified on the SiO2 surface to introduce the reactive double bonds. The MPS@SiO2 was either random- or block-copolymerized with PMMA through RAFT polymerization. The PMMA/SiO2 composites prepared via these different methods were characterized using FTIR, TGA, and DSC to determine their chemical structures, thermal degradation temperatures, and glass transition temperatures, respectively. Scanning electron microscopy (SEM) was employed to observe the microstructures and dispersion of the composites. This comprehensive analysis revealed that the PMMA/SiO2 composites prepared via block copolymerization exhibited thermal stability at temperatures between 200 and 300 °C. Additionally, they demonstrated excellent transparency (86%) and scratch resistance (≥6H) while maintaining mechanical strength, suggesting their potential application in thermal insulation materials. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
42. Investigation of Sodium Hydroxide on the Electrolysis and Silica based Nano Fluid on the Performance of Proton Exchange Membrane Fuel Cell.
- Author
-
Satyanarayana, Addala and Naidu, I. E. S.
- Subjects
PROTON exchange membrane fuel cells ,RENEWABLE energy sources ,NANOFLUIDS ,SILICA nanoparticles ,SPECIFIC gravity - Abstract
Energy efficiency is a global need to decrease net emissions and optimise the use of renewable energy sources. Ongoing research focuses on optimizing the use of renewable energy resources to maximize their consumption. Fuel cells, which utilise water to generate electricity, are among these renewable energy resources. Nevertheless, as previously said, there is ongoing research focused on optimising the synthesis of hydrogen and the extraction of voltage and current. In this study, we present the utilisation of sodium hydroxide (NaOH) in the extraction of hydrogen and silica nanoparticles for the enhancement of power values. The experiment clearly demonstrates that using a 50% NaOH solution resulted in the production of about 5.602 litres of hydrogen gas. Furthermore, the molar percentage of hydrogen in the final product was determined to be 85.74%. The gas chromatography analysis findings indicate that the product contains 81.58% hydrogen, 11.62% nitrogen, and 0.04% carbon dioxide. The electrical efficiency achieved is 86% with a heat loss of 13.96%. In addition, the research included the introduction of silica nanoparticles into the water. It was noted that this led to an increase in power density when the relative humidity was about 70%. The study also revealed that these nanoparticles had the potential to boost fuel cell performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. Antibacterial Activity of Superhydrophobic-SiO 2 Coatings to Inhibit the Growth of Escherichia coli and Staphylococcus aureus.
- Author
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Sánchez-Santamaria, Betania, Cornejo-Monroy, Delfino, Olivas-Armendáriz, Imelda, Arias-Cerón, José Saúl, Villanueva-Montellano, Alfredo, Ordoñez-Casanova, Elsa, Dávalos-Ramírez, José Omar, Martínez-Gómez, Erwin Adán, and Jaquez-Muñoz, Jesús Manuel
- Subjects
SUBSTRATES (Materials science) ,CONTACT angle ,BACTERIAL adhesion ,TRANSMISSION electron microscopy ,SILICA nanoparticles - Abstract
The emergence of superhydrophobic antibacterial materials represents a promising approach to maintaining surface cleanliness and hygiene by effectively preventing bacterial adhesion. This research outlines the synthesis of a superhydrophobic coating with anti-adhesion and bacteriostatic properties, utilizing silica nanoparticles (SiO
2 NPs) modified with 1H,1H,2H,2H-Perfluorodecyltriethoxysilane (PFDTES). Transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy were conducted to analyze the coating's morphology and surface characteristics. The coating was applied to glass substrates using the spray coating method, and the number of layers was varied to evaluate its antibacterial and bacteriostatic properties. These properties were measured using turbidimetry and inhibition halo techniques. Additionally, the durability of the coatings was assessed by exposing them to outdoor conditions for 35 days. This study aimed to evaluate the antibacterial and bacteriostatic capacities of the superhydrophobic coating, along with its resistance to outdoor weathering. The results indicate that a superhydrophobic coating with a contact angle ≥ 150° and a sliding angle ≤ 10° was successfully synthesized using SiO2 NPs smaller than 10 nm, modified with PFDTES. The coating demonstrated an ability to inhibit bacterial growth by preventing the adhesion of bacteria such as Escherichia coli and Staphylococcus aureus. Furthermore, the number of coating layers significantly influenced its bacteriostatic efficacy. The coating also exhibited strong durability under outdoor conditions. These findings highlight the potential application of superhydrophobic coatings for the prevention of bacterial adhesion and growth in environments where such contamination poses risks. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
44. Highly sensitive multiplexed colorimetric lateral flow immunoassay by plasmon-controlled metal–silica isoform nanocomposites: PINs
- Author
-
Minsup Shin, Wooyeon Kim, Kwanghee Yoo, Hye-Seong Cho, Sohyeon Jang, Han-Joo Bae, Jaehyun An, Jong-chan Lee, Hyejin Chang, Dong-Eun Kim, Jaehi Kim, Luke P. Lee, and Bong-Hyun Jun
- Subjects
Colorimetric lateral flow immunoassays ,Multicolored metal nanoparticles ,Silica nanoparticles ,Seed mediated growth method ,Multiplex analysis ,Technology ,Chemical technology ,TP1-1185 ,Biotechnology ,TP248.13-248.65 ,Science ,Physics ,QC1-999 - Abstract
Abstract Lateral flow assay (LFA) systems use metal nanoparticles for rapid and convenient target detection and are extensively studied for the diagnostics of various diseases. Gold nanoparticles (AuNPs) are often used as probes in LFAs, displaying a single red color. However, there is a high demand for colorimetric LFAs to detect multiple biomarkers, requiring the use of multicolored NPs. Here, we present a highly sensitive multiplexed colorimetric lateral flow immunoassay by multicolored Plasmon-controlled metal–silica Isoform Nanocomposites (PINs). We utilized the localized surface plasmon resonance effect to create multi-colored PINs by precisely adjusting the distance between the NPs on the surface of PINs through the controlled addition of reduced gold and silver precursors. Through simulations, we also confirmed that the distance between nanoparticles on the surface of PINs significantly affects the color and colorimetric signal intensity of the PINs. We achieved multicolored PINs that exhibit stronger colorimetric signals, offering a new solution for LFA detection with high sensitivity and a 33 times reduced limit of detection (LOD) while maintaining consistent size deviations within 5%. We expect that our PINs-based colorimetric LFA will facilitate the sensitive and simultaneous detection of multiple biomarkers in point-of-care testing. Graphical Abstract
- Published
- 2024
- Full Text
- View/download PDF
45. Investigation of Sodium Hydroxide on the Electrolysis and Silica based Nano fluid on the Performance of Proton Exchange Membrane Fuel Cell
- Author
-
Addala Satyanarayana and I.E.S. Naidu
- Subjects
fuel cell ,sodium hydroxide ,electrolysis ,silica nanoparticles ,relative humidity ,power density ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Energy efficiency is a global need to decrease net emissions and optimise the use of renewable energy sources. Ongoing research focuses on optimizing the use of renewable energy resources to maximize their consumption. Fuel cells, which utilise water to generate electricity, are among these renewable energy resources. Nevertheless, as previously said, there is ongoing research focused on optimising the synthesis of hydrogen and the extraction of voltage and current. In this study, we present the utilisation of sodium hydroxide (NaOH) in the extraction of hydrogen and silica nanoparticles for the enhancement of power values. The experiment clearly demonstrates that using a 50% NaOH solution resulted in the production of about 5.602 litres of hydrogen gas. Furthermore, the molar percentage of hydrogen in the final product was determined to be 85.74%. The gas chromatography analysis findings indicate that the product contains 81.58% hydrogen, 11.62% nitrogen, and 0.04% carbon dioxide. The electrical efficiency achieved is 86% with a heat loss of 13.96%. In addition, the research included the introduction of silica nanoparticles into the water. It was noted that this led to an increase in power density when the relative humidity was about 70%. The study also revealed that these nanoparticles had the potential to boost fuel cell performance.
- Published
- 2024
- Full Text
- View/download PDF
46. Natural agents derived Pickering emulsion enabled by silica nanoparticles with enhanced antibacterial activity against drug-resistant bacteria.
- Author
-
Yao, Yining, Feng, Jiayou, Ao, Niqi, Zhang, Ye, Zhang, Jun, Wang, Yue, Liu, Chao, Wang, Meiyan, and Yu, Chengzhong
- Subjects
- *
TEA tree oil , *BACTERIAL cell walls , *METHICILLIN-resistant staphylococcus aureus , *SILICA nanoparticles , *DRUG resistance in bacteria , *LYSOZYMES - Abstract
[Display omitted] • A novel natural antibacterial agents derived Pickering emulsion (FLTPE) has been designed for the first time. • FLTPE shows enhanced antibacterial performance due to synergistic bacterial cell wall and cell membrane dual destruction function. • FLTPE provides superior efficacy in healing drug-resistant bacteria-infected wounds in mice compared to ampicillin. The emergence of antibiotic-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) has become a global health challenge due to the overuse of antibiotics. Natural substances including enzymes and essential oils have shown great potential as alternative treatment options. However, the combinational use of these natural agents remains challenging due to the denaturation of enzymes upon direct contact with oil. In this study, we report the design of a Pickering emulsion containing two natural antibacterial agents, lysozyme and tea tree oil, stabilized by fractal silica nanoparticles. In this design, the enzyme activity is kept and the volatility problem of tea tree oil is mitigated. Due to synergistic bacterial cell wall digestion and membrane disruption functions, potent bactericidal efficacy in vitro against drug-resistant bacteria is achieved. The therapeutic potential is further demonstrated in a wound healing model with drug-resistant bacteria infection, better than a synthetic antibiotic, Ampicillin. This study opens new avenues for the development of natural product-based antimicrobial treatments with promising application potential. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
47. Fe-doped biodegradable dendritic mesoporous silica nanoparticles for starvation therapy and photothermal-enhanced cascade catalysis in tumor therapy.
- Author
-
Ye, Mengwei, Zhang, Weikang, Xu, Hongwei, Xie, Peiyu, Song, Luming, Sun, Xiaohan, Li, Yian, Wang, Siling, and Zhao, Qinfu
- Subjects
- *
GLUCOSE oxidase , *SILICA nanoparticles , *BEHAVIOR therapy , *TREATMENT effectiveness , *PHOTOTHERMAL conversion - Abstract
Scheme 1 (A) Scheme of the preparation process of GFDP. (B) The photothermal-enhanced cascade catalysis on tumor. [Display omitted] Combination therapies have attracted significant attention because they address the limitations of monotherapy while improving overall efficacy. In this study, we designed a novel nanoplatform, named GOx@Fe-DMSN@PDA (GFDP), by integrating Fe2+ into dendritic mesoporous silica nanoparticles (DMSN) and selecting glucose oxidase (GOx) as the model drug loaded into the DMSN pores. Additionally, we coated the surface of the DMSN with polydopamine (PDA) to confer pH/near infrared (NIR) light-responsive controlled-release behavior and photothermal therapy (PTT). The introduction of Fe2+ into the DMSN framework greatly improved biodegradability and enhanced the peroxidase (POD)-like activity of GFDP. In addition, GOx could consume glucose and generate hydrogen peroxide (H 2 O 2) within tumor cells to facilitate starvation therapy and enhance cascade catalysis. The PDA coating provided the DMSN with an intelligent response release ability, promoting efficient photothermal conversion and achieving the PTT effect. Cellular tests showed that under NIR light irradiation, GFDP exhibited a synergistic effect of PTT-enhanced starvation therapy and cascade catalysis, with a half-maximal inhibitory concentration (IC 50) of 2.89 μg/mL, which was significantly lower than that of GFDP without NIR light irradiation (18.29 μg/mL). The in vivo anti-tumor effect indicated that GFDP could effectively accumulate at the tumor site for thermal imaging and showed remarkable synergistic therapeutic effects. In summary, GFDP is a promising nanoplatform for multi-modal combination therapy that integrates starvation therapy, PTT, and cascade catalysis. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
48. Magnetically actuated cisplatin-loaded nanoparticle collectives enhance drug penetration for potentiated ovarian cancer chemotherapy.
- Author
-
Chen, Ying, Zhang, Qiang, Shen, Jian, Liu, Zhiran, Cui, Xiaoyu, Ma, Li, Zheng, Yuanyi, Wang, Longchen, and Ying, Tao
- Subjects
- *
CANCER chemotherapy , *IRON oxides , *TARGETED drug delivery , *SILICA nanoparticles , *MAGNETIC nanoparticles , *MESOPOROUS silica - Abstract
We propose a strategy utilizing magnetic nanoparticle collectives to enhance drug targeted delivery and penetration for potentiated ovarian cancer chemotherapy. The designed magnetic pH-responsive nanoparticle collectives could active deliver chemotherapeutics to the tumor site, and enhance drug penetration into deep tumors by the torque-force hybrid magnetic field, offering potentially clinically feasible strategy for enhancing tumor chemotherapy. [Display omitted] Chemotherapy is the main clinical treatment for ovarian cancer, but still faces challenges of low drug targeting efficiency and insufficient drug permeability. Drug-loaded nanoparticle collectives, which are actuated by magnetic field, could be targeted to a designated location and achieve targeted drug delivery. In this work, we report a strategy that utilizes magnetic mesoporous silica nanoparticles loaded with cis -diaminodichloroplatinum (Fe 3 O 4 @SiO 2 -CDDP) for targeted delivery of chemotherapeutic drugs and enhances penetration into deep tumors. The Fe 3 O 4 @SiO 2 -CDDP collectives actively moved to the target tumor site, and this movement was regulated by a magnetic actuation system. Under the action of a torque-force hybrid magnetic field (TFMF), Fe 3 O 4 @SiO 2 -CDDP could further penetrate into the interior of tumors and achieve pH-responsive drug release in the tumor environment. The feasibility of this strategy was verified in three-dimensional cell spheres in vitro and in a tumor-bearing mouse model in vivo. This magnetically actuated nanoparticle collectives enhanced drug penetration strategy provides a new paradigm for targeted drug delivery and potentiated tumor therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
49. The effect of charge screening for cationic surfactants on the rigidity of interfacial nanoparticle assemblies.
- Author
-
Siegel, Henrik, de Ruiter, Mariska, Niepa, Tagbo H.R., and Haase, Martin F.
- Subjects
- *
CONTACT angle , *SILICA nanoparticles , *INTERFACIAL tension , *MEMBRANE separation , *NANOPARTICLES , *PHASE separation - Abstract
This article examines the effect of CTAB on the interfacial rigidity of silica nanoparticle films at the oil/water interface. The authors demonstrate that increasing CTAB concentrations reduce the rigidity of the nanoparticle layer, which in turn influences the structural integrity of bicontinuous interfacially jammed emulsion gels (bijels). [Display omitted] • CTAB charge screening lowers interfacial rigidity of nanoparticle assemblies. • Modulation of charge screening via ionic strength. • Charge screening also promotes CTAB adsorption on silica nanoparticles. • Interfacial rigidity control enhances bijel uniformity and structure. Functionalizing colloidal particles with oppositely charged surfactants is crucial for stabilizing emulsions, foams, all-liquid structures, and bijels. However, surfactants can reduce the attachment energy, the driving force for colloidal self-assembly at interfaces. An open question remains on how the inherent interfacial activity of cationic surfactants influences the interfacial rigidity of particle-laden interfaces. We hypothesize that charge screening among cationic surfactants regulates the rigidity of oil/water interfaces by reducing the attachment energy of nanoparticles. We investigate the interfacial rigidity of cetyltrimethylammonium bromide (CTAB) functionalized silica nanoparticles (Ludox® TMA) by analyzing the shape deformation of 1,4-butanediol diacrylate (BDA) droplets under varying salt and alcohol concentrations. The nanoparticle packing density is assessed using scanning electron microscopy. Attachment energy is characterized through interfacial tension measurements, three-phase contact angle analysis, and CTAB adsorption studies. We also examine the effects of interfacial rigidities on the structure of bijel films formed via roll-to-roll solvent transfer-induced phase separation (R2R-STrIPS) using confocal laser scanning microscopy. Increasing salt and alcohol concentrations decrease the interfacial rigidity of CTAB-functionalized nanoparticle films by reducing the interfacial tension. The contact angle has a minor influence on the rigidity. These results indicate that CTAB charge screening weakens the nanoparticle attachment energy to the interface. Controlling the rigidity enables the mass production of bijel sheets with consistent flatness, which is crucial for their potential applications in catalysis, energy storage, tissue engineering, and filtration membranes. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
50. Specific buffer effects on the formation of BSA protein corona around amino-functionalized mesoporous silica nanoparticles.
- Author
-
Mura, Monica, Carucci, Cristina, Caddeo, Elena, Sovová, Šárka, Piludu, Marco, Pekař, Miloslav, Jachimska, Barbara, Parsons, Drew F., and Salis, Andrea
- Subjects
- *
ELECTRIC double layer , *SILICA nanoparticles , *INTERMOLECULAR forces , *ZETA potential , *ELECTROSTATICS - Abstract
[Display omitted] The effect of buffer species on biomolecules and biomolecule-nanoparticle interactions is a phenomenon that has been either neglected, or not understood. Here, we study the formation of a BSA protein corona (PC) around amino-functionalized mesoporous silica nanoparticles (MSN-NH 2) in the presence of different buffers (Tris, BES, cacodylate, phosphate, and citrate) at the same pH (7.15) and different concentrations (10, 50, and 100 mM). We find that BSA adsorption is buffer specific, with the adsorbed amount of BSA being 4.4 times higher in the presence of 100 mM Tris (184 ± 3 mg/g) than for 100 mM citrate (42 ± 2 mg/g). That is a considerable difference that cannot be explained by conventional theories. The results become clearer if the interaction energies between BSA and MSN-NH 2 , considering the electric double layer (E EDL) and the van der Waals (E vdW) terms, are evaluated. The buffer specific PC derives from buffer specific zeta potentials that, for MSN-NH 2 , are positive with Tris and negative with citrate buffers. A reversed sign of zeta potentials can be obtained by considering polarizability-dependent dispersion forces acting together with electrostatics to give the buffer specific outcome. These results are relevant not only to our understanding of the formation of the PC but may also apply to other bio- and nanosystems in biological media. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
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