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BACKGROUND: The determination of (nano)particulate content from food additives has been a long-standing concern for authorities since it is of vital importance for ensuring food safety, regulatory adherence, and transparent consumer information. Nonetheless, a critical step in these determinations is the refinement of a careful and quantitative extraction process for particles that may be found within complex matrices such as confectionery products. The development of new technologies and analysis methods for nanoparticles is ongoing. Whereas new technologies and analysis methods for nanoparticles are being developed, the extraction of (nano)particles of different nature has not been adequately addressed in the literature. RESULTS: A simple aqueous extraction procedure was found to be suitable for the simultaneous extraction of TiO2 and SiO2 (nano)particles from five confectionery products. Neither the extraction agents (water, lipase, pancreatin and Tris-HCl solutions) nor the methods (manual shaking, ultrasonic bath, ultrasonic probe and ultrafiltration) altered the size, morphology, or aggregation state of either type of particle, as revealed by the micrographs obtained by Transmission Electron Microscopy (TEM). Single-particle ICP-MS (spICP-MS) determined that the optimal conditions for extracting both types of particles involve manual shaking using water as the solvent. Furthermore, the use of enzymes seemed to hinder the determination of both types of particles by spICP-MS. (Nano)particles of TiO2 and SiO2 were detected in all the confectionaries, even though the E171 additive was only labeled in one of them. The average percentage of nanoparticulate TiO2 material in the evaluated products was 30 %, while no nanometer-sized particles of SiO2 were detected. SIGNIFICANCE: Ensuring food safety, regulatory compliance and transparent consumer information relies on getting reliable results that connect with the application of sample treatment procedures for detecting unaltered nanoparticles in food products. The presented research introduces an economical, swift, user-friendly, environmentally responsible, and harmonious extraction method for the concurrent analysis of TiO2 and SiO2 particles in confectionery samples. Furthermore, particles from additives not included in the labeling have been detected, characterized, and quantified in the confectionary products.
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Nanopartículas , Dióxido de Silicio , Titanio , Titanio/química , Dióxido de Silicio/química , Nanopartículas/química , Agua/química , Tamaño de la PartículaRESUMEN
Background: Breast cancer presents significant challenges due to the limited effectiveness of available treatments and the high likelihood of recurrence. iRGD possesses both RGD sequence and C-terminal sequence and has dual functions of targeting and membrane penetration. iRGD-modified nanocarriers can enhance drug targeting of tumor vascular endothelial cells and penetration of new microvessels, increasing drug concentration in tumor tissues. Methods: The amidation reaction was carried out between SiO2/AuNCs and iRGD/PTX, yielding a conjugated drug delivery system (SiO2/AuNCs-iRGD/PTX, SAIP@NPs). The assessment encompassed the characterization of the morphology, particle size distribution, physicochemical properties, in vitro release profile, cytotoxicity, and cellular uptake of SAIP@NPs. The tumor targeting and anti-tumor efficacy of SAIP@NPs were assessed using a small animal in vivo imaging system and a tumor-bearing nude mice model, respectively. The tumor targeting and anti-tumor efficacy of SAIP@NPs were assessed utilizing a small animal in vivo imaging system and an in situ nude mice breast cancer xenograft model, respectively. Results: The prepared SAIP@NPs exhibited decent stability and a certain slow-release effect in phosphate buffer (PBS, pH 7.4). In vitro studies had shown that, due to the dual functions of transmembrane and targeting of iRGD peptide, SAIP@NPs exhibited strong binding to integrin αvß3, which was highly expressed on the membrane of MDA-MB-231 cells, improving the uptake capacity of tumor cells, inhibiting the rapid growth of tumor cells, and promoting tumor cell apoptosis. The results of animal experiments further proved that SAIP@NPs had longer residence time in tumor sites, stronger anti-tumor effect, and no obvious toxicity to major organs of experimental animals. Conclusion: The engineered SAIP@NPs exhibited superior functionalities including efficient membrane permeability, precise tumor targeting, and imaging, thereby significantly augmenting the therapeutic efficacy against breast cancer with a favorable safety profile.
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Neoplasias de la Mama , Oro , Nanopartículas del Metal , Ratones Desnudos , Oligopéptidos , Dióxido de Silicio , Animales , Dióxido de Silicio/química , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Humanos , Oligopéptidos/química , Oligopéptidos/farmacocinética , Oligopéptidos/farmacología , Oro/química , Oro/farmacocinética , Oro/farmacología , Ratones , Línea Celular Tumoral , Nanopartículas del Metal/química , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones Endogámicos BALB C , Paclitaxel/química , Paclitaxel/farmacología , Paclitaxel/farmacocinética , Paclitaxel/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/farmacocinética , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Tamaño de la Partícula , Células MCF-7RESUMEN
Water pollution with heavy metals owing to industrial and agricultural activities have become a critical dilemma to humans, plants as well as the marine environment. Therefore, it is of great importance that the carcinogenic heavy metals present in wastewater to be eliminated through designing treatment technologies that can remove multiple pollutants. A novel green magnetic nano-composite called (Carbonized Chitosan-Fe3O4-SiO2) was synthesized using Co-precipitation method to adsorb a mixture of heavy metal ions included; cobalt (Co2+), nickel (Ni2+) and copper (Cu2+) ions from aqueous solutions. The novelty of this study was the synthesis of a new nano-composite which was green with magnetic properties to be more sustainable and environmentally friendly. Its magnetic properties made it separated easily from solutions after accomplishment of the adsorption process using a magnet. Extended Freundlich isotherm was the best fitted model with maximum adsorption capacity of the metal ions mixture 2908.92 mg/g. Different experimental parameters have been studied included the initial concentration for a mixture of nickel, cobalt and copper metal ions (0.05-0.1 molar), dosage of adsorbent (0.5-3.5 g/L) and contact time (6-90 min) to investigate their changing effect on the removal percents of the heavy metal ions mixture from aqueous solutions. The experimental adsorption percent of cobalt ion ranged from 1.58 to 64.28%, nickel ion adsorption percent ranged from 10.68 to 94.12% and copper ion adsorption percent ranged from 4.41 to 76.23% at pH = 9 were based on the combination of the adsorption process parameters.
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A method of sequential spraying of polyvinyl alcohol with carbon quantum dots (PVA@CDs) aqueous suspension and SiO2 aqueous suspension is proposed to rapidly prepare multicolor dual-mode anti-counterfeiting labels. With the optimization of the concentration (15%) of colloidal microspheres in the SiO2 aqueous suspension as well as the spraying process parameters (spray distance of 10 cm, spray duration of 3 s, and assembly temperature of 20 °C), different-sized SiO2 microspheres (168 nm, 228 nm, and 263 nm) were utilized to rapidly assemble red, green, and blue photonic crystals. Furthermore, the tunable fluorescence emission of carbon quantum dots endows the labels with yellow, green, and blue fluorescence. The constructed dual-mode labeling was used to develop an anti-counterfeiting code with dual-channel information storage capabilities and also to create dual-mode multicolor anti-counterfeiting labels on various packaging substrates. This work provides a novel solution for anti-counterfeiting packaging and information storage.
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Aim: Agar-based phantoms are popular in high intensity focused ultrasound (HIFU) studies, with magnetic resonance imaging (MRI) preferred for guidance since it provides temperature monitoring by proton resonance frequency (PRF) shift magnetic resonance (MR) thermometry. MR thermometry monitoring depends on several factors, thus, herein, the PRF coefficient of agar phantoms was estimated. Materials and Methods: Seven phantoms were developed with varied agar (2, 4, or 6% w/v) or constant agar (6% w/v) and varied silica concentrations (2, 4, 6, or 8% w/v) to assess the effect of the concentration on the PRF coefficient. Each phantom was sonicated using varied acoustical power for a 30 s duration in both a laboratory setting and inside a 3T MRI scanner. PRF coefficients were estimated through linear trends between phase shift acquired using gradient sequences and thermocouple-based temperatures changes. Results: Linear regression (R 2 = 0.9707-0.9991) demonstrated a proportional dependency of phase shift with temperature change, resulting in PRF coefficients between -0.00336 ± 0.00029 and -0.00934 ± 0.00050 ppm/°C for the various phantom recipes. Weak negative linear correlations of the PRF coefficient were observed with increased agar. With silica concentrations, the negative linear correlation was strong. For all phantoms, calibrated PRF coefficients resulted in 1.01-3.01-fold higher temperature changes compared to the values calculated using a literature PRF coefficient. Conclusions: Phantoms developed with a 6% w/v agar concentration and doped with 0%-8% w/v silica best resemble tissue PRF coefficients and should be preferred in HIFU studies. The estimated PRF coefficients can result in enhanced MR thermometry monitoring and evaluation of HIFU protocols.
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Materials with a soft tissue regenerative capacity can be produced using biopolymer scaffolds and nanomaterials, which allow injured tissue to recover without any side effects or limitations. Four formulations were prepared using polyvinyl alcohol (PVA) and chitosan (CS), with silicon dioxide nanoparticles (NPs-SiO2) incorporated using the freeze-drying method at a temperature of -50 °C. TGA and DSC showed no change in thermal degradation, with glass transition temperatures around 74 °C and 77 °C. The interactions between the hydroxyl groups of PVA and CS remained stable. Scanning electron microscopy (SEM) indicated that the incorporation of NPs-SiO2 complemented the freeze-drying process, enabling the dispersion of the components on the polymeric matrix and obtaining structures with a small pore size (between 30 and 60 µm) and large pores (between 100 and 160 µm). The antimicrobial capacity analysis of Gram-positive and Gram-negative bacteria revealed that the scaffolds inhibited around 99% of K. pneumoniae, E. cloacae, and S. aureus ATCC 55804. The subdermal implantation analysis demonstrated tissue growth and proliferation, with good biocompatibility, promoting the healing process for tissue restoration through the simultaneous degradation and formation of type I collagen fibers. All the results presented expand the boundaries in tissue engineering and regenerative medicine by highlighting the crucial role of nanoparticles in optimizing scaffold properties.
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Quitosano , Liofilización , Nanopartículas , Alcohol Polivinílico , Dióxido de Silicio , Ingeniería de Tejidos , Andamios del Tejido , Quitosano/química , Alcohol Polivinílico/química , Dióxido de Silicio/química , Andamios del Tejido/química , Nanopartículas/química , Ingeniería de Tejidos/métodos , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Medicina Regenerativa/métodos , Regeneración/efectos de los fármacosRESUMEN
Liquid-filled hard gelatin capsules may have pertinent advantages both for therapeutic effect and extemporaneous preparations of medicines. Alpha lipoic acid is a substance used in medicines and dietary supplements and there is a need for creating an appropriate formulation which would be suitable for each individual patient or consumer. Based on its biopharmaceutical and physical chemical characteristics, eight different capsule formulations were designed and characterized. Silicon dioxide was added to form a semisolid content and prevent leakage. The formulation filled with alpha lipoic acid solution in polyethylene glycol 400 showed the best performance. Although the addition of silicon dioxide to the formulation with polyethylene glycol 400 led to a change in both flow character and viscosity, the release rate did not show a statistically significant decrease (more than 85% of content was released after 5 min testing). Applied technique is a simple and an appropriate approach for compounding and could be used for other substances with similar properties.
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Bed bugs are considered a major public health problem in industrialized countries. Usually, bed bug infestations are managed using a combination of physical and chemical methods. In recent years, new strategies for bed bug control have emerged, particularly the use of dusts like diatomaceous earth and silicon dioxide. However, in Europe, the use of silicon dioxide is restricted to professional, while diatomaceous earth can be harmful to the lungs. This study aimed to assess bed bug mortality rates associated with Sommières earth, green clay, talc, and sodium bicarbonate compared to silicon dioxide and diatomaceous earth from a pest management company, diatomaceous earth for litter conditioner, and diatomaceous earth from a supermarket. We tested permanent exposure, short exposure, horizontal transfer and repellent effect on two bed bug colonies. Sommières earth demonstrated efficacy ranging from 75% to 100% in permanent and short exposures, similar to the efficacy of diatomaceous earth from the pest management company. On the contrary, diatomaceous earth for litter conditioner and diatomaceous earth from a supermarket, green clay, talc, and sodium bicarbonate were found to be ineffective. This study demonstrates, for the first time, the efficacy of Sommières earth against bed bugs, but also highlights the variability in efficacy of diatomaceous earths on bed bugs depending on their quality.
Title: Lutte contre les punaises de lit avec des poudres : comparaison de l'efficacité du dioxyde de silicium, de la terre de diatomée et de la terre de Sommières. Abstract: Les punaises de lit sont considérées comme un problème de santé publique majeur dans les pays industrialisés. Habituellement, les infestations de punaises de lit sont gérées en utilisant une combinaison de méthodes physiques et chimiques. Ces dernières années, de nouvelles stratégies de lutte contre les punaises de lit ont vu le jour, notamment l'utilisation de poudres comme la terre de diatomées et le dioxyde de silicium. Cependant, en Europe, l'usage du dioxyde de silicium est réservé aux professionnels tandis que la terre de diatomées peut être nocive pour les poumons. Cette étude visait à évaluer les taux de mortalité des punaises de lit associés à la terre de Sommières, à l'argile verte, au talc et au bicarbonate de sodium par rapport au dioxyde de silicium, à la terre de diatomées d'une entreprise de lutte antiparasitaire, à la terre de diatomées pour conditionneur de litière et à la terre de diatomées d'un supermarché. Nous avons testé l'exposition permanente, l'exposition courte, le transfert horizontal et l'effet répulsif sur deux colonies de punaises de lit. La terre de Sommières a démontré une efficacité allant de 75% à 100% en exposition permanente et courte, similaire à l'efficacité de la terre de diatomées d'une entreprise de lutte antiparasitaire. Au contraire, la terre de diatomées pour conditionneur de litière et la terre de diatomées d'un supermarché, l'argile verte, le talc et le bicarbonate de sodium se sont révélés inefficaces. Cette étude démontre, pour la première fois, l'efficacité de la terre de Sommières contre les punaises de lit mais met également en évidence la variabilité de l'efficacité des terres de diatomées sur les punaises de lit en fonction de leur qualité.
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Chinches , Tierra de Diatomeas , Control de Insectos , Dióxido de Silicio , Talco , Animales , Chinches/efectos de los fármacos , Control de Insectos/métodos , Polvo/análisis , Arcilla/química , Bicarbonato de Sodio/farmacologíaRESUMEN
Recycled soda-lime glass powder is a sustainable material that is also often considered a filler in cement-based composites. The changes in the surface properties of the glass particles due to the treatments were analyzed by X-ray photoelectron spectroscopy (XPS) and optical spectroscopy. We have found that there is a relatively high level of carbon contamination on the surface of the glass particles (around 30 at.%), so plasma technology and thermal annealing were tested for surface cleaning. Room temperature plasma treatment was not sufficient to remove the carbon contamination from the surface of the recycled glass particles. Instead, the room temperature plasma treatment of recycled soda-lime glass particles leads to a significant enhancement in their room temperature photoluminescence (PL) by increasing the intensity and accelerating the decay of the photoluminescence. The enhanced blue PL after room-temperature plasma treatment was attributed to the presence of carbon contamination on the glass surface and associated charge surface and interfacial defects and interfacial states. Therefore, we propose blue photoluminescence under UV LED as a fast and inexpensive method to indicate carbon contamination on the surface of glass particles.
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Infectious coryza (IC) is an acute upper respiratory disease of chicken caused by Avibacterium (A.) paragallinarum. This disease results in an increased culling rate in meat chicken and a marked decrease in egg production (10% to more than 40%) in laying and breeding hens. Vaccines were first used against IC and effectively controlled the disease. Nanotechnology provides an excellent way to develop a new generation of vaccines. NPs have been widely used in vaccine design as adjuvants and antigen delivery vehicles and as antibacterial agents; thus, they can be used as inactivators for bacterial culture. In this research, the antibacterial effects of several nanoparticles (NPs), such as silicon dioxide with chitosan (SiO2-CS), oleoyl-chitosan (O.CS), silicon dioxide (SiO2), and iron oxide (Fe3O4), on A. paragallinarum were studied. Additionally, different A. paragallinarum vaccines were made using the same nanomaterials at a concentration of 400 µg/ml to help control infectious coryza disease in chicken. A concentration of 400 µg/ml of all the NPs tested was the best concentration for the inactivation of A. paragallinarum. Additionally, this study showed that the infectious coryza vaccine adjuvanted with SiO2 NPs had the highest immune response, followed by the infectious coryza vaccine adjuvanted with Fe3O4 NPs, the infectious coryza vaccine adjuvanted with SiO2-CS NPs, and the infectious coryza vaccine adjuvanted with O.CS NPs in comparison with the infectious coryza vaccine adjuvanted with liquid paraffin (a commercial vaccine).
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Adyuvantes Inmunológicos , Pollos , Quitosano , Nanopartículas , Enfermedades de las Aves de Corral , Animales , Pollos/inmunología , Enfermedades de las Aves de Corral/prevención & control , Enfermedades de las Aves de Corral/inmunología , Nanopartículas/química , Quitosano/química , Adyuvantes Inmunológicos/farmacología , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Dióxido de Silicio/química , Adyuvantes de Vacunas , Polímeros/química , Portadores de Fármacos/química , Pasteurellaceae/inmunologíaRESUMEN
The evolution of a multilayer sample surface during focused ion beam processing was simulated using the level set method and experimentally studied by milling a silicon dioxide layer covering a crystalline silicon substrate. The simulation took into account the redeposition of atoms simultaneously sputtered from both layers of the sample as well as the influence of backscattered ions on the milling process. Monte Carlo simulations were applied to produce tabulated data on the angular distributions of sputtered atoms and backscattered ions. Two sets of test structures including narrow trenches and rectangular boxes with different aspect ratios were experimentally prepared, and their cross sections were visualized in scanning transmission electron microscopy images. The superimposition of the calculated structure profiles onto the images showed a satisfactory agreement between simulation and experimental results. In the case of boxes that were prepared with an asymmetric cross section, the simulation can accurately predict the depth and shape of the structures, but there is some inaccuracy in reproducing the form of the left sidewall of the structure with a large amount of the redeposited material. To further validate the developed simulation approach and gain a better understanding of the sputtering process, the distribution of oxygen atoms in the redeposited layer derived from the numerical data was compared with the corresponding elemental map acquired by energy-dispersive X-ray microanalysis.
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Silicon dioxide nanoparticles (SiO2-NPs) can be found in many products, such as composites, paints, ceramics, consumer products, and food additives. We recently demonstrated that via breastfeeding, SiO2-NPs transfer to the offspring's brain, interfering negatively with hippocampus development. In this work, we evaluated the protective effect of grape seed extract (GSE) against the adverse effects of SiO2-NPs. After delivery, animals were administered 25 mg/kg SiO2-NPs with/without GSE (300 mg/kg) for 20 days (from 2nd to 21st days post-delivery) by gavage. SiO2-NPs increased malondialdehyde concentration and decreased antioxidant activity in the offspring's hippocampi. The mean number of dark neurons (DNs) was significantly higher in the hippocampi of the SiO2-NPs group, whereas the mean number of DCX + cells was significantly lower than in the control group. The offspring in the SiO2-NPs groups had a weak cognitive performance in adulthood. Interestingly, these adverse effects of SiO2-NPs were alleviated in the GSE-treated groups. Therefore, GSE can attenuate the damaging effects of maternal exposure to SiO2-NPs during lactation.
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Extracto de Semillas de Uva , Hipocampo , Nanopartículas , Dióxido de Silicio , Animales , Extracto de Semillas de Uva/farmacología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Dióxido de Silicio/toxicidad , Femenino , Ratas , Masculino , Embarazo , Ratas Wistar , Efectos Tardíos de la Exposición Prenatal/prevención & control , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Síndromes de Neurotoxicidad/prevención & control , Antioxidantes/farmacología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Fármacos Neuroprotectores/farmacologíaRESUMEN
Electrospun nanofibers have been used as wound dressings to protect skin from infection and promote wound healing. In this study, we developed polyvinylpyrrolidone (PVP)/silicon dioxide (SD) composite nanofibers for the delivery of probiotic Saccharomyces cerevisiae (SC), which potentially aids in wound healing. PVP/SD composite nanofibers were optimized through electrospinning, and bead-free nanofibers with an average diameter of 624.7 ± 99.6 nm were fabricated. Next, SC, a wound-healing material, was loaded onto the PVP/SD composite nanofibers. SC was encapsulated in nanofibers, and nanofibers were prepared using SC, PVP, SD, water, and ethanol in a ratio of 3:4:0.1:4.8:1.2. The formation of smooth nanofibers with protrusions around SC was confirmed using SEM. Nanofiber dressing properties were physicochemically and mechanically characterized by evaluating SEM, DSC, XRD, and FTIR images, tensile strength, and elongation at break. Additionally, a release test of active substances was performed. The absence of interactions between SC, PVP, and SD was confirmed through physicochemical evaluation, and SEM images showed that the nanofiber dressing contained SC and had a porous structure. It also showed a 100% release of SC within 30 min. Overall, our study showed that SC-loaded PVP/SD composite nanofibers prepared using the electrospinning method are promising wound dressings.
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Silicon nanoparticles (Si NPs) have an eminent role in improving plant yield through improving yield. The present study was conducted to find the effect of Si NPs on plant yield, biochemical attributes, and minerals of different cucumber cultivars. The greenhouse experiment with foliar application of Si NPs (100, 200, and 300 mg L-1) was carried out on cucumber cultivars (Emilie, Mirsoltan, Mitio, and Viola). The application of Si NPs at 300 mg L-1 led to the highest fruit yield, with a 17% increase in fruit production compared to the control. Fruit firmness differed by 31% between Emilie and Si NPs at 100 mg L-1 and Mito at 300 mg L-1. Plants experiencing Si NPs at 300 mg L-1 had the greatest chlorophyll (Chl) a+b. Compared to the other cultivars, Mito had a greater fruit yield and Chl content. The Si NPs increased TSS by 11% while lowering TA by 24% when compared to the control at 300 mg L-1. Foliar application of Si NPs reduced the value of TSS/TA. The largest value of K was reached in the Mito cultivar with Si NPs at 200 mg L-1, with a 22% increase in comparison to the control, indicating that Si NPs considerably boosted the K content. The Si NPs at 200 mg L-1 significantly increased leaf N and P in the Mito cultivar by 16 and 50%, respectively. By using agglomerative hierarchy clustering (AHC), Emilie and Mito were located in two separate clusters, whilst Viola and Mirsoltan were grouped in one cluster. In conclusion, Si NPs at 200-300 mg L-1 enhanced fruit yield, and Mito showed the highest yield when compared to other cultivars.
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Cucumis sativus , Frutas , Hojas de la Planta , Silicio , Cucumis sativus/efectos de los fármacos , Silicio/farmacología , Nanopartículas , Minerales , ClorofilaRESUMEN
Several organisms are able to polycondensate tetraoxosilicic(IV) acid to form silicon(IV) dioxide using polycationic molecules. According to an earlier mechanistic proposal, these molecules undergo a phase separation and recent experimental evidence appears to confirm this model. At the same time, polycationic proteins like lysozyme can also promote polycondensation of silicon(IV) dioxide, and they do so under conditions that are not compatible with liquid-liquid phase separation. In this manuscript we investigate this conundrum by molecular simulations.
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Muramidasa , Dióxido de Silicio , Muramidasa/química , Muramidasa/metabolismo , Dióxido de Silicio/química , Simulación de Dinámica Molecular , Polielectrolitos/químicaRESUMEN
The structure and handling properties of a P407 hydrogel-based bone substitute material (BSM) might be affected by different poloxamer P407 and silicon dioxide (SiO2) concentrations. The study aimed to compare the mechanical properties and biological parameters (bone remodeling, BSM degradation) of a hydroxyapatite: silica (HA)-based BSM with various P407 hydrogels in vitro and in an in vivo rat model. Rheological analyses for mechanical properties were performed on one BSM with an SiO2-enriched hydrogel (SPH25) as well on two BSMs with unaltered hydrogels in different gel concentrations (PH25 and PH30). Furthermore, the solubility of all BSMs were tested. In addition, 30 male Wistar rats underwent surgical creation of a well-defined bone defect in the tibia. Defects were filled randomly with PH30 (n = 15) or SPH25 (n = 15). Animals were sacrificed after 12 (n = 5 each), 21 (n = 5 each), and 63 days (n = 5 each). Histological evaluation and histomorphometrical quantification of new bone formation (NB;%), residual BSM (rBSM;%), and soft tissue (ST;%) was conducted. Rheological tests showed an increased viscosity and lower solubility of SPH when compared with the other hydrogels. Histomorphometric analyses in cancellous bone showed a decrease of ST in PH30 (p = .003) and an increase of NB (PH30: p = .001; SPH: p = .014) over time. A comparison of both BSMs revealed no significant differences. The addition of SiO2 to a P407 hydrogel-based hydroxyapatite BSM improves its mechanical stability (viscosity, solubility) while showing similar in vivo healing properties compared to PH30. Additionally, the SiO2-enrichment allows a reduction of poloxamer ratio in the hydrogel without impairing the material properties.
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Sustitutos de Huesos , Durapatita , Hidrogeles , Poloxámero , Ratas Wistar , Dióxido de Silicio , Animales , Masculino , Poloxámero/química , Poloxámero/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Durapatita/química , Durapatita/farmacología , Dióxido de Silicio/química , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Ratas , Ensayo de Materiales , Reología , Tibia/metabolismoRESUMEN
The present work develops an effective bioadsorbent of cross-linked chitosan-genipin/SiO2 adsorbent (CHI-GNP/SiO2). The developed CHI-GNP/SiO2 was employed for the removal of organic dye (reactive orange 16, RO16) from simulated wastewater. The optimization of the fundamental adsorption variables (CHI-GNP/SiO2 dose, time, and pH) via the Box-Behnken design (BBD) was attained for achieving maximal adsorption capacity and high removal efficiency. The good agreement between the Freundlich isotherms and empirical data of RO16 adsorption by CHI-GNP/SiO2 indicates that the adsorption process follows a multilayer adsorption mechanism. The reasonable agreement between the pseudo-second-order model and the kinetic data of RO16 adsorption by CHI-GNP/SiO2 was obtained. The maximum RO16 adsorption capacity (qmax) of CHI-GNP/SiO2 was identified to be 57.1 mg/g. The adsorption capacity of CHI-GNP/SiO2 is attributed to its unique surface properties, including its highly porous structure and the presence of functional groups such as amino and hydroxyl groups. According to the results of this investigation, CHI-GNP/SiO2 has the potential to be an adsorbent for the removal of acidic dyes from wastewater.
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Compuestos Azo , Quitosano , Dióxido de Silicio , Contaminantes Químicos del Agua , Purificación del Agua , Quitosano/química , Dióxido de Silicio/química , Adsorción , Compuestos Azo/química , Compuestos Azo/aislamiento & purificación , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Cinética , Purificación del Agua/métodos , Concentración de Iones de Hidrógeno , Modelos Estadísticos , Aguas Residuales/química , Colorantes/química , Colorantes/aislamiento & purificación , IridoidesRESUMEN
Although nanoparticles have gained attention as efficient alternatives to conventional agricultural chemicals, there is limited knowledge regarding their effects on herbivorous insect behavior and plant physicochemistry. Here, we investigated the effects of foliar applications of nano-silica (SiO2NPs) and nano-selenium (SeNPs), and bulk-size silica (SiO2) on the choice behavior of the arrowhead scale insect on mandarin orange plants. One leaf of a bifoliate pair was treated with one of the three chemicals, while the other was treated with water (control). The respective SiO2, SeO2, calcium (Ca), and carbon (C) content levels in the leaf epidermis and mesophyll were quantified using SEM-EDX (or SEM-EDS); leaf toughness and the arrowhead scale density and body size were measured. First-instar nymphs preferred silica-treated leaves and avoided SeNP-treated leaves. SiO2 content did not differ between control and SiO2NP-treated leaves, but was higher in bulk-size SiO2-treated leaves. The SiO2 level in the control leaves was higher in the SiO2NP treatment compared with that in the control leaves in the bulk-size SiO2 treatment. Silica-treated leaves increased in toughness, but SeNP-treated leaves did not; leaf toughness increased with mesophyllic SiO2 content. The insect density per leaf increased with leaf toughness, SiO2 content and, in the SiO2NP treatment, with epidermal C content. There was no correlation between SeO2 content and insect density. This study highlights the potential uses of SeNPs as an insect deterrent and of silica for enhancing leaf toughness and attracting scale insects.
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An inorganic/organic nanocomposite was used to develop an afterglow and color-tunable smart window. A combination of polylactic acid (PLA) plastic waste as an environmentally-friendly hosting agent, and lanthanide-activated strontium aluminum oxide nanoparticles (SAON) encapsulated with silica nanoparticles (SAON@Silica) as a photoluminescent efficient agent resulted in a smart organic/inorganic nanocomposite. In order to prepare SAON-encapsulated silica nanoparticles (SAON@Silica), the SAON nanoparticles were coated with silica using the heterogeneous precipitation method. By using transmission electron microscopy (TEM), SAON showed a diameter range of 5-12 nm, while the SAON@Silica nanoparticles showed a diameter range of 50-100 nm. In order to ensure the development of a colorless plastic film, a homogeneous dispersion of the phosphorescent Phosphor@Silica nanoparticles throughout the plastic bulk was confirmed. CIE Lab coordinates and luminescence spectra were used to study the color shift characteristics. Under visible light conditions, the plastic films were transparent. The photoluminescent films emitted green light at 525 nm when excited at 375 nm. The hydrophobicity and ultraviolet protection were enhanced without altering the fundamental physico-mechanical performance of the plastic sheet. The current color-tunable plastic can be used in many potential applications, such as warning signs, anti-counterfeiting barcodes, smart windows, and protective apparel.
Asunto(s)
Metales de Tierras Raras , Nanopartículas , Dióxido de Silicio , Poliésteres , Óxido de Aluminio , AluminioRESUMEN
Long-term exposure to inhalable silica particles may lead to severe systemic pulmonary disease, such as silicosis. Exosomes have been demonstrated to dominate the pathogenesis of silicosis, but the underlying mechanisms remain unclear. Therefore, this study aimed to explore the roles of exosomes by transmitting miR-107, which has been linked to the toxic pulmonary effects of silica particles. We found that miR-107, miR-122-5p, miR-125a-5p, miR-126-5p, and miR-335-5p were elevated in exosomes extracted from the serum of patients with silicosis. Notably, an increase in miR-107 in serum exosomes and lung tissue was observed in the experimental silicosis mouse model, while the inhibition of miR-107 reduced pulmonary fibrosis. Moreover, exosomes helped the migration of miR-107 from macrophages to lung fibroblasts, triggering the transdifferentiation of cell phenotypes. Further experiments demonstrated that miR-107 targets CDK6 and suppresses the expression of retinoblastoma protein phosphorylation and E2F1, resulting in cell-cycle arrest. Overall, micron-grade silica particles induced lung fibrosis through exosomal miR-107 negatively regulating the cell cycle signaling pathway. These findings may open a new avenue for understanding how silicosis is regulated by exosome-mediated cell-to-cell communication and suggest the prospect of exosomes as therapeutic targets.