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Mesoporous silica nanoparticles (MSNs) have displayed high‐potential prospects in biomedical use, especially for drug delivery due to large surface area, tunable pore size and simple surface functionalization. The objective behind the present research is to synthesize and profile piperine‐modified MSNs for their preparation due to antioxidative anticarcinogenic, anti‐inflammatory properties of the alkaloid chosen as a modifier. In the study, silica piperine nanoparticles (SPN) were fabricated based on a modified Stöber method. Characterization techniques including SEM, TEM, AFM, FTIR, XRD, and DSC showed significant differences of incorporated piperine in the production process to plain MSN properties. Piperine was observed to inhibit nanoparticles’ growth so that they became smaller, heterogeneous, with a changed morphology and surface chemistry. As a strong confirmation of covalent incorporation, spectroscopic data showed the presence of electrons in the piperine's functional group that were exchanged into some silanol groups and removed excessive surface energy. The antioxidant activity of SPNs revealed that the silica matrix, and moreover bioactive piperine combination resulted to significant increase in enhanced antioxidant potential. In general, the results of this study offer meaningful lessons about the utilization and manipulation of piperine to suit MSN in a bid to optimize them for biomedical uses such as drug delivery applications where its antioxidant characteristics may bring therapeutic benefits. This holistic characterization and standardization of piperine‐modified MSNs sets the solid stage for further project practice and advance adjustment in aluminosilicate nanostructures designed for biomedical application. [ABSTRACT FROM AUTHOR]

Highlights Incorporating inorganic particles is a common approach to preparing polymeric materials with desirable physical properties and processability. However, this often results in increased brittleness, necessitating methods to improve melt strength and toughness. In this study, in situ polymerization was employed to functionalize silica nanoparticles with the silane coupling agent (3‐aminopropyl) triethoxysilane (APTES) as a core. A flexible chain segment, poly(butylene itaconate) (PBI), was then introduced as a “rubbery” intermediate layer, resulting in a core‐shell structure of poly(L‐lactic‐co‐butanediol itaconate) nano‐silica copolymer films (PLBISiO2) with both branched and “rubbery” structures. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) confirmed the formation of macromolecular chains, with the molecular weight (Mn) of PLBI increasing from 59,638 to 74,306 g/mol. This significant increase supports the “rubbery” core‐shell structure. When 0.5% SiO2 was added, the T5% of the film increased by 40°C, significantly improving thermal stability. Additionally, the elongation at break increased to 265.7%, while retaining the original tensile strength. Dynamic rheology experiments further confirmed the generation of branched or “rubbery” core‐shell structures, and a doubling of gas barrier properties was observed with increased silica nanoparticles, suggesting potential applications in food packaging or biopharmaceuticals. Nanocomposites with core‐shell structure and improved mechanical properties. Dynamic rheology experiments confirmed the formation of the core‐shell structure. Significantly improved gas barrier properties due to core‐shell structure. [ABSTRACT FROM AUTHOR]

In this research, magnetic mesoporous silica nanoparticles decorated with SnO2 quantum dots (M‐MSNs/SnO2[QDs]) were successfully synthesized and characterized using several advanced techniques including FT‐IR, XRD, FE‐SEM, EDS, elemental mapping, VSM, and BET. This study demonstrates the synthesis of benzo[a]pyrano[3,2‐c]phenazine derivatives via a four‐component reaction between 2‐hydroxy‐1,4‐naphthoquinone, ortho‐phenylenediamine, malononitrile, and benzaldehyde derivatives in the presence of M‐MSNs/SnO2(QDs) in ethanol as a green solvent. The proposed catalyst efficiently catalyzed the synthesis of these compounds with yields of 87–96% in 70–100 minutes. The presented method offers a cost‐effective and environmentally friendly approach with numerous advantages, including high product yields, simple operation, short reaction times, low‐cost purification, and facile catalyst recovery. [ABSTRACT FROM AUTHOR]

The incorporation of natural products into a suitable delivery system has the potential to augment their therapeutic effectiveness significantly. In this study, we demonstrate how silicasomes, a lipid‐coated mesoporous silica nanorods, influence the anticancer potency and release behaviour of the natural product. Piperlongumine (Pip), a natural product isolated from long pepper, is loaded into mesoporous silica nanorods (MSNRs) followed by a bilayer coating made of 1,2‐Dimyristoyl‐sn‐glycero‐3‐phosphocholine (DMPC). The size and morphology of Pip‐loaded MSNRs (Pip@MSNRs) and phospholipid‐coated Pip@MSNRs (PL‐Pip@MSNRs) are characterized well using suitable analytical techniques. The release of Pip from Pip@MSNRs attained saturation at 48 h while PL‐Pip@MSNRs exhibited the same only after 100 h in both simulated physiological and endolysosomal acidic environments. Moreover, PL‐Pip@MSNRs displayed a higher percentage of Pip release in an acidic medium than in a physiological medium after 24 h. These results confirm that the DMPC coating could assist the pH‐responsive and sustained release of loaded drug from silica nanorods. Most importantly, PL‐Pip@MSNRs demonstrate a higher potency of cytotoxicity and apoptosis against MCF‐7 (Human Breast Carcinoma) cells than the Pip@MSNRs, emphasizing the significance of DMPC‐coated MSNRs as a suitable nanocarrier for natural product delivery. [ABSTRACT FROM AUTHOR]

Converting carbon dioxide into formic acid with formate dehydrogenase (FDH) as a catalyst is a gentle and eco‐friendly process that not only conserves energy and reduces emissions but transforms waste into valuable resource. Enzyme immobilization is a common strategy for improving the stability and recyclability of enzyme, however, the procedures are usually complicated that include surface modification and binding reactions in order to form reliable linkages. Co‐deposition of polydopamine (PDA) with polyethyleneimine (PEI) is a popular surface modification approach in versatile fields, but their co‐deposition with enzymes is rarely reported. Herein, one‐pot immobilization of FDH on SiO2 nanoparticles based on catechol chemistry was attempted for the first time with or without PEI, and the resultant immobilized enzymes, FDH/PDA/PEI‐SiO2 and FDH/PDA‐SiO2, were characterized, and the effects of the composition and deposition conditions on the catalytic performance were investigated. FDH/PDA‐SiO2 exhibited a higher apparent specific activity than FDH/PDA/PEI‐SiO2, which was separately 0.167 and 0.136 mM/h/mg. The activity recovery rate was 464% and 378% of that of free enzyme. After 5 cycles, their relative activity was 82.3% and 87.4%. This research is significant in presenting a simple and high‐efficient one‐pot immobilization method that can be extended to other kinds of enzymes. [ABSTRACT FROM AUTHOR]

Partially hydrolyzed polyacrylamide is extensively utilized in enhanced oil recovery operations. However, its efficacy is compromised by mechanical degradation during transport through injection lines, valves, and reservoir, which leads to a reduction in the average molecular weight, diminishing the solution's viscosity and viscoelastic properties, critical for efficient oil displacement. In this investigation, we characterized the degree of mechanical degradation in HPAM solutions by evaluating shear and extensional rheological parameters preand post‐degradation. Mechanical degradation was induced by subjecting them to controlled flow through a valve featuring varying degrees of constriction and flow rates. Our results demonstrate a significant reduction in zero‐shear viscosity and high‐strain extensional viscosity of mechanically degraded solutions, with reductions of up to 64%. To mitigate this issue, we explored the incorporation of silica nanoparticles as a potential remedy for mechanical degradation. These nanoparticles strengthen the network structure of HPAM, thereby reducing its susceptibility to mechanical degradation. Our findings reveal that shear and extensional viscosities of mechanically degraded NPs‐HPAM solutions experienced only minimal reductions, dropping to 12% and 0%, respectively. This underscores the effectiveness of the nanoparticle‐enhanced HPAM solutions in preserving viscosity and viscoelasticity under mechanical stress, presenting a promising avenue for improving the robustness of EOR processes. [ABSTRACT FROM AUTHOR]

A robust method for enhancing the dispersion and stabilization of small metal nanoparticles in heterogeneous catalysts is developed. It involves in situ complexation of palladium(II) by histidine, in water, prior to impregnation in fumed silica. TEM images show that the histidine facilitates dispersion of the Pd(II) into finer nanoscale particles (≈2 nm) uniformly distributed on the support, rather than the large clusters (≈5 nm) seen in the absence of histidine. After hydrogen reduction, assessments using CO chemisorption and propylene hydrogenation indicate that the coordinated histidine might obscure the active sites on the Pd particles. However, as histidine decomposes between 220 and 300 °C in air, these materials are treated at 225 °C in air for 48 h. Afterwards the Pd(II) particles remain the same size, but after hydrogen reduction, there is a 2.4‐fold increase in CO gas adsorption, indicative of an expanded Pd surface area. Furthermore, superior catalyst stability (activity >200 h) is observed during propylene hydrogenation at 250 °C. This is consistent with histidine use having generated widely spaced, uniformly small, Pd nanoparticles on the silica support which is expected to help prevent agglomeration (sintering) during catalysis. This is a convenient low‐cost strategy for reducing metal content, preventing sintering and optimizing catalyst performance. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusion This research investigates how particle parameters, such as zeta potential, size, functional group, material composition, and hydrophobicity affect their affinity and deposition of particles onto hair.Streaming potential was used as the technique for analysis. The streaming potential data obtained was then converted to surface coverage data. Scanning electron microscopy (SEM) was also done to visualize particle localization on the hair surface.This study found stronger particle affinity on healthy than on damaged (oxidatively bleached) hair, due to diminished interaction sites from the removal of the hair shaft's external lipid layer. SEM imaging supported these findings and offered insights into particle localization. Hydrophilic silica particles accumulated along the exposed hydrophilic cuticle edges of healthy hair, due to hydrogen bonding with the exposed endocuticle. This localization is hypothesized to be due to the limited hydrophilic binding sites on the hydrophobic healthy hair cuticle surface. In damaged hair, an abundance of hydrophilic sites across the cuticle surface results in more dispersed binding. Hydrogen bonding and electrostatic attraction were shown to be the predominant forces influencing deposition, with hydrophobic interactions playing a less influential role. The affinity studies also proved that electrostatic attractions work over a longer range and are more effective at lower particle conditions compared with hydrogen bonding which only start to play a bigger role at higher particle concentrations. Steric hindrance of bulky side groups acted as a significant repulsive force. Results also revealed that larger particles deposit poorly on both healthy and damaged hair compared with smaller ones. Compared with neutrally charged silica nanoparticles (SN‐2), positively charged PMMA particles (PN+16) have a stronger affinity to healthy hair, with highly charged particles (PN+49) depositing most rapidly.This study provides a fundamental understanding of how particle–surface parameters influence their affinity to hair and how damaging hair affects deposition. [ABSTRACT FROM AUTHOR]

Singlet oxygen is a powerful oxidant used in various applications, such as organic synthesis, medicine, and environmental remediation. Organic and inorganic photosensitizers are commonly used to generate this reactive species through energy transfer with the triplet ground state of oxygen. We describe here a series of novel benzophenazine derivatives as a promising class of photosensitizers for singlet oxygen photosensitization. In this study, we investigated the structure‐activity relationship of these benzophenazine derivatives. Akin to a molecular compass, the southern fragment was first functionalized with either aromatic tertiary amines, alkyl tertiary amines, aromatic sulfur groups, alkyl sulfur groups, or cyclic ethers. Enhanced photophysical properties (in terms of triplet excited‐state lifetime, absorption wavelength, triplet state energy, and O2 quenching capabilities) were obtained with cyclic ether and sulfur groups. Conversely, the presence of an amine moiety was detrimental to the photocatalysts. The western and northern fragments were also investigated and slightly undesirable to negligible changes in photophysical properties were observed. The most promising candidate was then immobilized on silica nanoparticles and its photoactivity was evaluated in the citronellol photooxidation reaction. A high NMR yield of 97 % in desired product was obtained, with only a slight decrease over several recycling runs (85 % in the fourth run). These results provide insights into the design of efficient photosensitizers for singlet oxygen generation and the development of heterogeneous systems. [ABSTRACT FROM AUTHOR]

The authors, actively engaged in the development of mesoporous silica‐based solutions, initially for modified drug release, later for the smart administration of conventional chemotherapeutic cytotoxic drugs, present the evolution of the concept of targeted therapy across different disciplines. They also discuss the diverse therapeutic needs and related challenges (adverse drug effects) that have unfolded over the last 30 years. Nanomedicine potentialities, mainly against cancers, that have emerged globally during the intense research activity of the last few decades, are critically discussed. The authors glimpse the growing potential of immune‐based therapeutic solutions, including those assisted by nanotechnology, as well as molecular targeted therapies (MTT) on which they focus. The advantages offered by targeted molecular therapies, despite the limits of monotargeted therapies, suggest the engineering of multi‐targeted therapies. Nanomedicine solutions such as ligand‐specific internalization and pH‐sensitive drug release that they have extensively tested and recently presented in open literature, still remain available instruments. According to the authors, MTT can offer shining perspectives in the near future that will depend on a thorough comprehension of nanostructures synthesis and tumor physiology. This article gives an interdisciplinary point of view tailored for non‐specialist readers imagining possible future scenarios in the field. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Biological cells exhibit diverse phenomena induced through linking of chemical reactions of molecules and solid surface contact. It is then a significant topic in the field of chemistry to study phenomena induced through this linking using synthetic systems, which can promote our understanding of biological phenomena and can be applied to the development of novel functions. Silica nanoparticles (SNPs), which are synthetic inorganic materials, are attractive for such purposes, because of their following characteristics: they can adsorb large amounts of molecules on their surfaces, they can aggregate through contact between SNPs as well as contact between molecules and SNPs, and the molecules can be easily removed from solutions by precipitation. The contact of SNP surfaces with molecules then affects chemical reactions of molecules and also behaviors of SNPs. This article describes systems derived from synthetic helical molecules and SNPs, which exhibit notable phenomena including selective adsorption and molecular recognition, equilibrium shift, step kinetics with induction period, precipitation with flow and sweeping, and disaggregation and desorption by sonication, in which the high affinity of helical molecules with SNP surfaces plays important roles. Mechanistic models that explain the phenomena are provided. Possible applications are also discussed, including the separation of molecules, capture of intermediates, the storage and release of molecules, equilibrium shift, clocking, and the translation of mechanical stimulations into chemical reactions. Key Scientists: [ABSTRACT FROM AUTHOR]

Superhydrophilic coatings are prominent in various industries, including automotive, and consumer electronics. However, challenges persist in terms of mechanical performance and durability. This study focuses on the development of organic–inorganic hybrid nanoparticles for superhydrophilic coatings that exhibit exceptional thermomechanical stability and long‐term durability. Employing green chemistry, polyethylene glycols (PEGs) are grafted onto silica nanoparticles, controlling the PEG molecular weight from 200 to 1000 to systematically investigate its impact on coating characteristics. Additionally, the intriguing phenomenon of phase separation facilitated by a polyurethane binder and its effects on both morphology and hydrophilicity is investigated. All hybrid coatings consistently exhibit remarkable superhydrophilicity, with contact angles consistently below 10°, the lowest being 1.4°. Longer PEG chains played a pivotal role in enhancing the thermal stability of the grafted PEG shell within the hybrid nanoparticles, achieving a maximum enhancement in decomposition temperature of 150 °C. Furthermore, the PEG shell substantially improves strain durability, with SiO2‐PEG 1000–50% exhibiting outstanding transmittance retention of 100% without any cracks even under a 100% tensile strain. SiO2‐PEG 200 emerged as the champion in maintaining superhydrophilicity throughout a 20‐day long‐term durability assessment. Moreover, the research has unveiled the intricate degradation mechanism responsible for the decline in hydrophilicity in these hybrid coatings. [ABSTRACT FROM AUTHOR]

Nanotechnological applications involving the fabrication of potential nanomaterials and novel strategies for mitigation of contaminants have helped a lot in environmental cleanup. The chemical route for silica nanoparticle (NPs) synthesis using tetra ethyl oxy silicone and tetramethyl oxy silicone is expensive and energy intensive. Silica NPs synthesis from coal fly ash waste could prove to be economical. In this study, the investigators have used coal fly ash for silica NPs synthesis via a noble and economical approach. This biosynthetic approach involved two steps: (1) extraction of crude sodium silicate by using alkali treatment of fly ash and (2) the addition of crude sodium silicate to the supernatant of Fusarium oxysporum for fabrication of silica NPs. The developed silica NPs are analyzed by the analytical instruments where the microscopic techniques revealed 10–50 nm‐sized floral‐shaped mycogenic silica NPs. The X‐ray diffraction revealed the amorphous nature of the silica NPs with a broad spectrum starting from 8º and ending at 23º having centered at 13.1°. Fourier transform infrared spectroscopy, in region 400–1200 cm−1, exhibited three distinguishing bands for silica NPs. The current study reports a novel and effective method for the development of silica NPs with a high yield and purity of about 95%. [ABSTRACT FROM AUTHOR]

Silica is a frequently used material for removing organic contaminants, dyes, and metal ions from wastewater due to its large specific surface area and ease of preparation at various porosities. In a wide range of pH values, a negative charge is created on its surface as a result of the deprotonation of silanols, which causes its strong adsorption properties in alkaline media. It is found that a composite material consisting of mesoporous silica with iron oxide nanoparticles, which have a point of zero charge (PZC) much larger than silica, can exhibit strong adsorption properties in acidic media as well. This is confirmed by the analysis of the Zeta potential and a significant increase in the adsorption of methylene blue by modified silica at pH values of 4 and above. It is also showed that the microscopic mechanism underlying this behavior relies on the coexistence of two length scales: the Debye shielding range for Coulombic interactions and the average pore size where the iron oxide nanoparticles are synthesized. [ABSTRACT FROM AUTHOR]

Vanadium redox flow battery (VRFB) is a very promising solution for large‐scale energy storage, but some technical issues need to be addressed. Crossover, i.e., the undesired permeation of vanadium ions through the cell separator, causes capacity loss and self‐discharge. Low‐cost and highly selective separators are thus required to improve the competitiveness of this technology. This work investigates the use of silica nanoparticles in an innovative selective layer to improve membrane selectivity and reduce its thickness. 1.5 μm thick barrier layers composed of 1100EW Nafion ionomer with silica (≈3–13 nm diameter) and Vulcan XC‐72R (≈40 nm) nanoparticles in different proportions are directly deposited on 50 μm thick Nafion membranes. The barrier layer composed only of silica nanoparticles reduces the self‐discharge due to crossover by 5 times and increases the average efficiency of the battery. Finally, during more than 1000 h of operation, the barrier layer on a 25 μm Nafion membrane demonstrates excellent stability, working with a constant coulombic efficiency higher than 99% and a capacity decay rate comparable with a thicker Nafion membrane, thus enabling the use of thinner membranes in VRFB, allowing an estimated 8% stack costs reduction with respect to NR212. [ABSTRACT FROM AUTHOR]

Microcapsules have attracted significant attention in academia and industry due to their unique properties for protecting and controlling the release of active substances. However, based on water‐insoluble biopolymers, developing a straightforward approach to prepare microcapsules with improved biocompatibility and functional shells remains a great challenge. In this study, zein, a water‐insoluble protein, is employed to prepare robust microcapsules facilely using oil‐in‐aqueous ethanol Pickering emulsions as templates. First, the emulsion template is stabilized by hydrophobic silica nanoparticles with in situ surface modification of tannic acid. The zein is then precipitated at the interface in a controlled manner using antisolvent approach to obtain silica/tannic acid/zein (STZ) microcapsules. It is found that the concentration of zein and the presence of tannic acid played a significant role in the formation of STZ microcapsules with well‐defined morphology and a robust shell. The uniform deposition of zein on the surface of template droplets is facilitated by the interactions between tannic acid and zein via hydrogen bond and electrostatic force. Finally, the resulting STZ microcapsules showed super resistance to ultraviolet (UV) radiation and high temperature for the unstable, lipophilic, and active substance of β‐carotene. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is the most aggressive and common adult brain tumor. Current therapies primarily involve surgical resection, followed by chemotherapy and radiotherapy. However, the low survival rate due to high toxicity, side effects, and poor targeting necessitates novel treatments. Post‐transcriptional regulation pathways, particularly the regulation of alternative polyadenylation based on the mRNA 3′UTR, play a critical role in cell growth and development and the progression of tumors. Targeting tumor cells and reprogramming the 3′UTR of tumor suppressor genes to achieve post‐transcriptional regulation is expected to be a new channel for GBM therapy. Herein, a novel siRNA delivery system is developed based on mesoporous silica nanoparticles: siRNA composite nanoparticles (siRNA CNP). Encapsulation in MSNs overcomes siRNA degradation and cellular entry issues, while lipid bilayer coating improves biocompatibility and stability. Surface‐modified nucleic acid aptamer SL1 (Apt‐SL1) significantly enhances GBM targeting, offering therapeutic potential. The findings show that siRNA CNP effectively silences the promoter CFIm25 of distal poly(A) in tumor cells, inducing gene reprogramming, inhibiting tumor growth, and promoting apoptosis in nude mice. The siRNA CNP demonstrates a significant effect in reprogramming tumor suppressor genes and treating GBM. It offers a novel and promising therapeutic avenue for GBM. [ABSTRACT FROM AUTHOR]

This study investigates the temperature‐dependent micellization behaviors of saponin and sodium dodecyl sulfate (SDS) surfactants, which are both important for chemical enhanced oil recovery (CEOR). It also evaluates the effect of silica nanoparticles (SiO2) on these behaviors, given the growing interest in nanoparticle‐enhanced surfactants. The research focuses on the tunable properties of nanoparticle‐surfactant combinations. The structural differences between saponin and SDS were identified using FT‐IR and H‐NMR. The Du Noüy ring method was used to measure surface tension at various concentrations and temperatures (25–75 °C). FTIR analysis showed distinct differences between SDS and Saponin, associated with head group where there is hydroxyl groups in SDS solution. H‐NMR showed higher complexity of Saponin's structure, evidenced by its diverse sugar‐related proton peaks. Both SDS and Saponin reduce surface tension with temperature; SDS is more effective, lowering it to 42.1 mN/m versus 48.5 mN/m for Saponin. With SiO2, tensions drop to 39.2 mN/m for SDS and 45.5 mN/m for Saponin. Both surfactants maintain CMCs under reservoir temperature in the 0.05–0.1 wt % range. Saponin exhibited a more negative ΔG° and consistently negative ΔH°, indicating a thermodynamically favorable exothermic reaction. The novelty of this study lies in its focus on both anionic and nonionic surfactants under simulated reservoir conditions. The study focuses on the role of nanoparticles in enhancing surfactant stability and efficiency by addressing thermodynamic parameters. [ABSTRACT FROM AUTHOR]

Phosphor‐in‐silica glass (PiSG) composite is an excellent candidate for highly stable and efficient color converter in high power white light emitting diodes (wLEDs). However, the high‐throughput fabrication of PiSG with different shapes is still challenging for current techniques. Here this study reports the manufacture of transparent PiSG based on YAG:Ce (Y3Al5O12:Ce3+) using injection molding (IM) technique. In this approach, different shapes of centimeter‐sized YAG:Ce‐PiSG pieces are fabricated by using IM of a YAG:Ce/amorphous silica nanoparticles/thermoplastic polymer composite at low temperatures (@ 150 °C) which afterward are debound (@ 600 °C) and densified (@ 1150 °C). Interestingly, the molding time to produce YAG:Ce/silica/polymer green parts is 5 s per piece, implying the capability for high‐throughput production of YAG:Ce‐PiSG. Furthermore, the as‐fabricated YAG:Ce‐PiSG exhibits high luminescence efficiency (>91%) and high chemical/thermal stabilities. Accordingly, high power wLEDs (10 W) are fabricated using the YAG:Ce‐PiSG which demonstrates high luminous efficiency of 144 lm W−1 at 50 mA, closing to that of the wLEDs fabricated by expensive YAG:Ce ceramic plate (i.e., 149 lm W−1 @ 50 mA). The work provides a facile and universal approach for industry‐scale production of PiSG that can be promising for various photonic applications. [ABSTRACT FROM AUTHOR]

The current study used the melt mixing approach to create a variety of agar/SiO2 nanoparticle (AG/Si) nanocomposites films. Silica nanoparticles were included as a filler in different proportions, varying from 0% to 5% (w/w). The study examined how the composition impacted the chemical properties, mechanical characteristics, thermal properties, water vapor barrier, surface color, and antimicrobial capabilities. After the addition of SiO2, the tensile strength increased significantly from 30.77 to 40.97 MPa at 4% SiO2. Moreover, the presence of SiO2 was improved the contact angle from 53.81° to 63.24°, brightness of the film (L*) from 70.63 ± 3.34 up to 84.80 ± 2.26, maximum degradation temperature (Tdmax) from 315 to 317°C and melting temperature (Tm) from 109 to 125°C. In the meantime, following the integration of SiO2 content, the density of agar film dropped from 1.27 to 1.16 kg/m³. The AG/Si film effectively prevented bacterial growth and extended the shelf life of fresh beef, suggesting a novel biobased option for antimicrobial packaging film. [ABSTRACT FROM AUTHOR]

The reuse of waste and the use of renewable materials are of great environmental and economic interest. With that in mind, the synthesis of mesoporous silica can be performed using rice husk ash, which is an industrial waste generated in large quantities. This mesoporous material can be functionalized with photoactive molecules, enabling application in photocatalysis. In this work, we used mesoporous silica nanoparticles functionalized with rose bengal dye (RB) for photooxidation reactions of organic molecules, such as the antibiotic cefuroxime 1‐acetoxyethyl ester (cefuroxime axetil). The characterization results showed the formation of one‐dimensional channels with uniform size and two‐dimensional hexagonal arrangement, with surface area and pore diameter of 230 m2 g−1 and 5 nm, respectively. The infrared and UV‐Vis spectroscopy indicated the functionalization of silica with photoactive molecules. Finally, SBA‐15/RB was applied for the photooxidation of ascorbic acid and antibiotic cefuroxime axetil under irradiation with green light, proving to be efficient for the degradation of cefuroxime axetil. Investigation of the reactive oxygen species involved in photodegradation showed that the photooxidation mechanism mainly involves singlet oxygen. [ABSTRACT FROM AUTHOR]

Modulation of Si–O bonds under mild conditions has been a challenging issue in the field of material science, which is critical to manufacture high‐performance silica‐based optical and photonic devices. Herein, we introduce a nondestructive technique to achieve Si–O bond rearrangement, leading to plastic deformation and photoluminescence enhancement of amorphous silica nanoparticles using supercritical carbon dioxides in EtOH/H2O solution under mild temperature. Specifically, plastic deformation is achieved by treating hollow mesoporous silica nanospheres using supercritical CO2 at 40 °C under 20 MPa. Experimental and theoretical studies revealed the critical role of supercritical CO2 in the plastic deformation process, which can be intercalated into the hollow mesoporous silica nanospheres with anisotropic stresses and induces the rearrangement of Si–O bonds and transformation of ring structures. This work suggests a novel approach to engineer high‐performance nano‐silica glass components for numerous optical and photonic devices under mild condition. [ABSTRACT FROM AUTHOR]

BACKGROUND: Owing to their surface modifiability, smart mesoporous silica nanoparticles (MSNs) can be designed to respond to plant disease‐microenvironmental stimuli, thereby achieving on‐demand release of active ingredients to control disease by effectively improving citral (CT) stability. RESULTS: A pH/chitinase dual stimuli‐responsive essential oil‐delivery system (CT@HMS@CH/TA) was successfully fabricated by encapsulating CT in hollow mesoporous silica (HMS), and coating with tannic acid (TA) and chitosan (CH) within HMS by using the layer‐by‐layer assembly technique (LbL). CT@HMS@CH/TA with an average particle size of 125.12 ± 0.12 nm and a hollow mesoporous nanostructure showed high CT‐loading efficiency (16.58% ± 0.17%). The photodegradation rate of CT@HMS@CH/TA under UV irradiation (48 h) was only 15.31%, indicating a 3.34‐fold UV stability improvement. CT@HMS@CH/TA exhibited a higher CT release rate in response to acidic pH and the presence of chitinase, simulating the prevailing conditions as Magnaporthe oryzae infection. Furthermore, CT@HMS@CH/TA exhibited better adhesion without affecting normal rice growth, significantly upregulating chitinase gene expression and enhancing chitinase activity on M. oryzae, thus enhancing CT antifungal activity. CONCLUSION: CT@HMS@CH/TA improved CT stability and showed intelligent, controlled release‐performance and higher antifungal efficacy, thus providing a new strategy for efficient application of essential oils for green control of rice blast disease. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) has gained significant attention as a commercially available biodegradable and biocompatible polymer. However, the brittleness of PLA greatly limits its application. Blending PLA with another rubbery polymer such as thermoplastic polyurethane (TPU) is a simple strategy to toughen PLA. In this study, a largely toughened PLA has been successfully prepared by melt blending with TPU through interfacial compatibilization induced by the simultaneous addition of hydrophobic silica nanoparticles (NPs) and in situ cross‐linking reaction. The torque evolution during melt mixing and rheological analysis confirm a successful dynamic vulcanization process. Scanning electron microscopy images indicate that, dynamic vulcanization and adding NPs synergistically compatibilize the TPU and PLA phases leading to a considerable interfacial adhesion between the phases. Simultaneous addition of NPs at an optimum amount of 5 wt% and in situ cross‐linking reaction significantly improve the elongation at break, and tensile toughness of the PLA/TPU blend as they are achieved 311%, and 91 MJ/m3, respectively. Both dynamic vulcanization and NPs play their role independently in the compatibilization of PLA and TPU phases inducing substantial shear yielding of the matrix phase under stress resulting in a highly toughened blend. The microstructural properties of the blends are studied by rheological analysis. [ABSTRACT FROM AUTHOR]

Smart afterglow paints can function as energy‐saving products that are able to persist lighting in the dark. Additionally, polyurethane paints (PURPs) have shown some limitations, including weak adhesion, poor mechanical performance, poor corrosion, and low water resistance as compared with solvent‐based paints. Herein, nanoparticles of lanthanide aluminate (NLA; 16–24 nm) were mixed with polyurethane and silica to develop novel photoluminescent nanocomposite paints. A precursor of NLA‐encapsulated silica nanoparticles (NLA@Silica; 200–225 nm) can be described as a SiO2‐coated NLA pigment prepared by the heterogeneous precipitation method. Steel was coated with nanocomposite paints made of PURP, silica, and NLA. Using emission spectra and Commission Internationale de l'Eclairage (CIE) Lab coordinates, the coloring and transparency of painted films were investigated. Upon excitation at 365 nm, the UV‐irradiation of transparent painted films showed green emission at 518 nm. The hydrophobic activity and hardness properties were examined. Using electrochemical impedance spectroscopy (EIS), the anticorrosion of coatings applied to mild steel was studied. Improved anticorrosion characteristics were observed due to the fluorescence of NLA@Silica in the applied coatings. The optimal long‐lasting luminous characteristics were observed for nanocomposite films containing 12.5% of NLA@Silica. [ABSTRACT FROM AUTHOR]

Shear thickening fluid (STF), a highly concentrated mixture of nanosized silica particles in polyethylene glycol (PEG) is characterized by its quick transition to a stiff, solid‐like form under high shear rates. In this study, the modified Stöber synthesis approach was used for synthesizing the monodispersed spherical 300 nm silica nanoparticles. The rheological properties of the STF formulated using different silica loading were characterized. The Takshak model was tested to assess the rheological properties. The effect of the STFs on the impact resistance and yarn pull‐out force of the Kevlar® 802 fabric was determined. The uniformity in size of the silica nanoparticles facilitated more efficient packing within the fluid matrix, resulting in the formation of networks or structures that enhance shear thickening behavior. The STF with 70% silica exhibited the best peak viscosity of 45.8 Pa.s. Upon impregnation of this STF onto the Kevlar, a significantly high energy absorption (478.4%) compared to neat Kevlar, was observed. Moreover, the yarn pull‐out force for this system was found to be very high (435.8%). The reasons for the enhancement of the properties are explained. The novelty of this work lies in the synthesis of silica particles, analysis of the rheological properties, and interrelating the rheological properties with the characteristic parameters to define the impact characteristics. The improved properties underscore the suitability of synthesized STF for impact resistance applications. [ABSTRACT FROM AUTHOR]

Inspired by the strong adhesion of mussels, basalt fibers (BFs) were modified with polydopamine and then composited with nylon 6. The effect of polydopamine content on the interfacial interactions and mechanical properties of the composites was investigated. In addition, silica nanoparticles were grown on the surface of polydopamine‐modified BFs to investigate the synergistic effect. The study revealed that the mechanical properties of the composites based on polydopamine‐modified BF were gradually enhanced with the increase of the dopamine coverage concentration, and gradually decreased after reaching the peak. 0.5 g/L concentration of dopamine solution modified BFs showed the best enhancement effect on nylon 6, and its tensile strength could reach 133.1 MPa, which was 28.5% higher than that of the unmodified composites. The tensile strength of the composites modified with both dopamine and silica nanoparticles reached 157 MPa, which was 51.7% higher than that of the unmodified composites. In addition, scanning electron microscope images of fracture sections confirmed the strong interfacial interaction between BF and PA6. Highlights: The surface roughness of BF was increased by nano‐SiO2.Hydrogen bonding was formed between PDA and PA6.Physical interlock was formed between nano‐SiO2 and PA6.Tensile strength increased by 51.7% with both nano‐SiO2 and PDA.Stronger interfacial interaction leads to higher thermal stability. [ABSTRACT FROM AUTHOR]

Recently, mesoporous silica nanoparticles (MSNs) have emerged as promising candidates in the field of hemorrhage control owing to their extended pore size, high surface area, and excellent biocompatibility. These characteristics directly influence the toxicity of cells, the loading of therapeutic agents, and the release of active ions during the hemostasis process. Therefore, understanding the fundamentals of tuning these characteristics is important to design these types of carriers. While several literature reviews have explored the role of MSNs in hemorrhage control, comprehensive studies focusing on their general characteristics and specific applications remain scarce. This review concentrates on the principles of synthesizing mesoporous silica, the general types of MSNs, techniques for loading drugs methods onto the site of injury, release kinetics models, biocompatibility, toxicity, and the unique properties of MSNs. Furthermore, the article examines the mechanism of action of MSNs as nanomaterial hemostatic agents. [ABSTRACT FROM AUTHOR]

The development of thin‐film nanocomposite (TFN) membranes with high performance is conducive to efficient desalination and wastewater treatment. In this work, dendritic mesoporous silica nanoparticles (DLSiO2) were synthesized by a dual‐templating strategy. Afterward, they were introduced into the aqueous phase to fabricate TFN membranes via in situ interfacial polymerization (IP) reaction. Powerful techniques as scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, Nano zetasizer‐DLS, x‐ray photoelectron microscopy, electrokinetic analyzer, and contact angle were used in the characterization of dendritic structures and nanocomposite membranes. Results revealed that DLSiO2 with special structural characteristics can effectively regulate the IP process, promoting the enhancement of the crosslinking degree, surface hydrophilicity, and surface negative charge of polyaimde (PA) selective layers. It is also beneficial for constructing extra water channels within the PA selective layer to boost the transport of water molecules. As a consequence, the prepared TFN membrane with 0.3 mg/mL DLSiO2 exhibits optimal separation performance and good pressure resistance, acid–base resistance, and anti‐fouling properties. It also exhibited a water permeability of 4.17 L m−2 h−1 bar−1 (increased by 61.7% compared with thin film composites (TFC) membrane) and a NaCl rejection of 99.0%, which were better than those of TFN membranes prepared by introducing other types of silica in other studies. [ABSTRACT FROM AUTHOR]

Nanostructured materials possess promising potential for cancer therapy through precise adjustment of their functionalization and physicochemical attributes. This study primarily focuses on the synthesis and characterization of mesoporous silica nanoparticles (MSN) that are functionalized with titanocene dichloride (a therapeutic agent) and one of several amino acids—cysteine, captopril, penicillamine, or methionine—utilizing 3‐aminopropyltriethoxysilane (AP) as a linker. This synthesis yielded four innovative metallodrug‐functionalized nanostructured materials (MSN‐AP‐Cys‐Ti, MSN‐AP‐Cap‐Ti, MSN‐AP‐Pen‐Ti, and MSN‐AP‐Met‐Ti), meticulously characterized using diverse analytical techniques such as X‐ray diffraction (XRD), X‐ray fluorescence (XRF), diffuse reflectance ultraviolet–visible (DR UV–Vis), Fourier transform infrared (FTIR), solid‐state nuclear magnetic resonance (NMR) spectroscopy, and transmission electron microscopy (TEM). The textural properties of the nanomaterials post‐functionalization displayed slight modifications, confirming the successful integration of the therapeutic agents. Evaluation of cytotoxicity in the breast cancer cell line MDA‐MB‐231, with the healthy cell line Hek‐293T as control via MTT assays, revealed the active nature of the functionalized silica‐based materials. The viability of both cell lines indicated a concentration‐dependent response to the materials. Among the tested systems, cysteine and captopril exhibited the highest activity concerning IC50 relative to material concentration. The enhanced biological activity of higher functionalized nanosystems suggests a favorable cell internalization facilitated by the amino acid fragment. Additionally, qualitative DNA binding studies hinted at potential DNA adsorption on the surface of the metallodrug‐functionalized nanomaterials, forming DNA adducts where a strand of DNA covalently bonds to the metallodrug moiety. This was deduced from the hypsochromic shift in absorbance of the characteristic π–π* and n–π* transitions in DNA, which occurred from 1.01 to 0.76 and 1.26–0.19 following drug (MSN‐AP‐Cap‐Ti) interaction. [ABSTRACT FROM AUTHOR]

At present, Ag nanoparticles have been widely used as Raman substrates, but their easy oxidation and aggregation have limited practical applications. In order to address the above problems, firstly, tetraethyl orthosilicate as a precursor was applied to synthesis silver coated with silica dioxide nanoparticles (Ag@SiO2). As a result, the surface of Ag nanoparticles is uniformly coated with a thin layer of SiO2 in order to solve the easy oxidation problem without adversely affecting their surface‐enhanced Raman scattering (SERS) performance. Furthermore, Ag@SiO2 nanoparticles were electrostatically deposited onto polyamide (PA) films to form a two‐dimensional PA‐Ag@SiO2 film substrate, thus resolving nanoparticle agglomeration issues and further improving the repeatability of the entire system. As can been from the SERS detection results obtained from the probe molecules and pollutants, the Raman signal on the PA‐Ag@SiO2 thin film substrate has a good degree of sensitivity, stability, and repeatability. [ABSTRACT FROM AUTHOR]

This study investigates the mechanical properties and fracture behavior of polypropylene (PP)‐based blend‐nanocomposites comprising 30 wt.% ethylene–propylene–diene monomer (EPDM) and 5 wt.% SiO2 nanoparticles. Different mixing sequences were employed to prepare the nanocomposites, and the resulting morphology development and dispersion states of modifiers were analyzed. Mechanical performance of the nanocomposites was evaluated through quasi‐static and high‐speed dynamic fracture tests. The dispersion and distribution of SiO2 nanoparticles within the nanocomposites were significantly influenced by the mixing protocol. In impact fracture tests, the presence of nanoparticles exhibited a beneficial efffect on fracture energy, demonstrating a synergistic toughening effect of the soft EPDM and rigid SiO2 particles. Conversely, adverse effects were observed in quasi‐static tests. Essential work of fracture (EWF) parameters indicated an increase in the yielding component and a decrease in the necking‐to‐tearing component with SiO2 incorporation into the PP/EPDM blends. During impact loadings, the highest improvement in crack propagation resistance was observed in nanocomposites with nanoparticles localized around the rubbery domains forming a network‐like structure of EPDM/SiO2‐nanoparticles. Morphologies where rubber domains and nanoparticles were separately distributed in the PP matrix resulted in the lowest fracture parameters. Energy dissipation mechanisms were elucidated, revealing multiple void formation followed by matrix shear yielding as the primary source under both quasi‐static and impact fracture conditions. In the latter case, stress‐concentrating percolated structures in the PP matrix facilitated the nucleation of dilatational bands evolving into highly stretched void‐fibrillar structures upon further loading. These findings contribute valuable insights into tailoring nanocomposite morphologies for enhanced mechanical performance in different loading scenarios. Highlights: Fracture behavior of PP/EPDM/SiO2 ternary systems was evaluated by EWF methodology and Izod impact test.Rubber particles surrounded by silica nanoparticles led to a percolated morphology and as a result to superior impact resistance.EWF parameters were mostly controlled by the tearing‐related parts regardless of phase morphology.The impact toughness was mainly controlled by the dispersion and distribution characteristics of the SiO2 nanoparticles. [ABSTRACT FROM AUTHOR]

The aviation sector is continually seeking ways to reduce the weight of aircraft structures without compromising their mechanical integrity. Lightweight materials, such as advanced epoxy sandwich composites with hybrid nanostructures, have the potential to significantly contribute to fuel efficiency, thereby addressing environmental concerns and operational costs. This research investigates the mechanical properties of hybrid sandwich polymer composites filled with silica nanoparticles (SNiPs). Epoxy isocyanate (PU) foam sandwich composites were fabricated with kevlar fiber, carbon fiber, and glass fiber, constructed by alternating inclined interply bidirectional fiber and foam layers. SNiPs were introduced into the composite system at varying percentages, such as 0, 2, 4, and 6 wt%. The study employs a systematic approach, incorporating experimental testing, to assess key mechanical parameters, including tensile strength, flexural strength, and shear strength. The test results indicate that the incorporation of SNiPs improved the mechanical properties of the composites, leading to enhanced strength, toughness, and modulus of elasticity. Incorporation of composite laminates with 4 wt% SiNPs resulted in improved three‐point bending, tensile, shear, and torsional strengths, with maximum values of ca. 64, ca. 5, ca. 2 MPa, and ca. 22 Nm, respectively. The findings contribute to the ongoing pursuit of materials that can meet the stringent demands of modern aviation, ultimately paving the way for advancements in aircraft construction and design. [ABSTRACT FROM AUTHOR]

The preparation of four types of epoxidized iron‐based comb butadiene‐isoprene rubber (EBIR) with different epoxidation degrees (4.7%, 6.4%, 10.2%, and 12.3%) was investigated for the first time in this study. The modification involved the use of hydrogen peroxide and formic acid as raw materials for the epoxidation process. Following this, silica/EBIR composites were prepared by mixing EBIR with silica nanoparticles, without the use of a silane coupling agent (SCA). The objective was to investigate the influence of the epoxidation degree on the structure and properties of the resulting silica/EBIR nanocomposites. The results indicated that the introduction of epoxy groups had a positive effect on the interfacial interaction between the rubber and filler, leading to improved dispersion of the silica nanoparticles in the rubber matrix. Consequently, the tensile properties, wet skid resistance, and abrasion resistance of the silica/EBIR composites were found to be superior to those of the un‐epoxidized silica/BIR composites. Furthermore, comparing the silica/EBIR‐12.3 nanocomposites with silica/BIR‐Si69 nanocomposites, it was revealed that silica/EBIR‐12.3 showed a 69.4% enhancement in wet skid resistance and an 8.0% reduction in rolling resistance. These findings demonstrate the potential of silica/EBIR composites for high‐performance tire tread rubber applications, offering environmental benefits and improved properties. [ABSTRACT FROM AUTHOR]

Nanosized zeolitic imidazolate frameworks (nZIFs) are being researched as 5‐fluorouracil (5‐FU) carriers for the treatment of cancer. The surface functionalization of ZIFs with periodic mesoporous organosilicas (PMOs) is expected to enhance stability and prevent the flocculation of nZIFs. In this study, ZIF‐7 nanomaterials and fluorescent organosilicas (FITC−APTES) were effectively introduced into PMO nanoparticles, and the resulting product was named ZIF‐7@PMO. The surface functionalization with the PMO nanoparticles enhanced the chemical stability of ZIF‐7 nanoparticles in ethanol. The study examined the impact of temperature on the synthesis of ZIF‐7@PMO and found that low temperatures were more conducive to the encapsulation of ZIF‐7 nanoparticles and fluorescent organosilica, as well as pore size retention. Moreover, the drug storage capacity of the ZIF‐7@PMO nanoparticles was evaluated via their loading and release of 5‐FU. The results revealed that the ZIF‐7@PMO nanoparticles could adsorb 5‐FU with a loading capacity of 100–140 mg g−1 for 24 h. ZIF‐7@PMO released half of 5‐FU amount within 8 h before releasing a maximum of 75 % within 3 days. Therefore, the fluorescent ZIF‐7@PMO nanoparticles could be a potential drug carrier in the field of controlled drug delivery. [ABSTRACT FROM AUTHOR]

A new strategy for a catalytic C−C bond forming cascade reaction comprising acetal hydrolysis and Knoevenagel condensation is presented here. The heterogeneous nanocatalyst is prepared by immobilizing an ionic liquid on the surface of highly monodisperse silica nanoparticles. This work is the first example of showing that there is no need to use bifunctional acid‐base catalysts for a cascade reaction including the hydrolysis of benzaldehyde dimethyl acetal to benzaldehyde and the subsequent Knoevenagel condensation of the resulting benzaldehyde with malononitrile. It is shown here that these reactions can proceed smoothly with a mono‐functional heterogeneous catalyst that contains a neutral ionic liquid. It has been proposed that such a neutral ionic liquid can "switch on" to an acidic catalyst in conjunction with water. The selected ionic liquid has potentially biodegradability characteristics, which is an important issue to achieve a sustainable catalyst. The simple procedure for preparing both the ionic liquid and the monodisperse silica nanoparticles provides opportunities for a large‐scale synthesis of the catalyst. This work introduces a breakthrough in the design and synthesis of heterogeneous catalysts for acid/base catalyzed cascade organic reactions. [ABSTRACT FROM AUTHOR]

The vulcanization process is widely used in industry for tire manufacturing. Therefore, zinc oxide is commonly utilized as an activator material, but unreacted zinc oxide remains in the final products and can be released into the environment with a significant impact. To reduce the amount of required zinc and to prevent leaching from tire material, zinc single site‐containing silica fillers are interesting candidates. In these materials, zinc sites are anchored on the surface of silica nanoparticles through their complexation with functionalized aminosilanes. Based on these, a novel powder sample is prepared via spray‐drying. The obtained supraparticles allow for a homogeneous distribution of the filler nanoparticles in the rubber matrix via their disintegration during the incorporation process. All synthesis steps are carried out in ethanol and water, respectively, at very mild temperatures to account for sustainability demands. As core of this study, the role of zinc ions and their amino‐complexation in nanoparticle dispersion stability and in supraparticle formation during spray‐drying is elucidated. Additionally, the superior performance of supraparticles as activator in rubber vulcanization is demonstrated. These show a higher curing efficiency, leading to lower curing time (−70%), higher torque values (+15%), and improved dynamic mechanical properties compared to the conventional ZnO activator. [ABSTRACT FROM AUTHOR]

This paper reports the results of polyethylene (PE) and polypropylene (PP) composites containing 5 and 10 wt.% dendritic fibrous nanosilica (DFNS) synthesized by a hydrothermal process. The objective of this investigation is to provide a better understanding of the relationship between the structure, composition, matrix‐nanofiller interfaces, and the properties of these nanocomposites. These materials have been prepared by twin‐screw extrusion and injection molding. Their structural, thermal, mechanical, rheological, and electrical properties were evaluated, both alone and when combined with an organic compatibilizing agent. Findings have shown that the unique morphology of fibrous silica nanoparticles was preserved and not altered by melt processing, indicating the high thermal and mechanical stability of these fibrous materials. The nanocomposites containing DFNS alone exhibited higher mechanical performances compared to those containing the surface modifier, with no observable effect on their thermal properties. Findings also showed that the interactions between the nanoparticles and polymer may influence the functional properties of the final nanocomposites, and that they are dependent on both the nature of the host polymer along with the presence of the surface modifier agent. Highlights: Well‐defined DFNS were successfully prepared.PE and PP based nanocomposites were successfully designed by twin‐screw extrusion.Good interfacial interactions were obtained with PP.Functional properties of the nanocomposites were influenced by the interfacial adhesion. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles (MSN) are emerging as one of the most appealing candidates for gene carriers. Nevertheless, one major obstacle for their clinical application is the lack of efficient controlled release and gene delivery. In this study, a mesoporous silica‐modified gold nanorods (Au NRs) controlled release platform was synthesized. Then a thermosensitive copolymer was grafted to the surface of release platform, to impart the switching response of carrier under the photothermal of Au NRs. Fluorination were modified on the surface of MSN through a disulfide bond to achieve glutathione (GSH) response release and improve serum‐resistant ability. This gene carrier, with notable DNA condensation ability and negligible cytotoxicity, could be easily internalized into cells, enhanced green fluorescent protein expression in the presence of serum under laser irradiation. This work inspired us to solve the problem of traditional controllable sustained release and realize the performance of intracellular switch response to gene sustained release. [ABSTRACT FROM AUTHOR]

The study conducted an extraction of pure amorphous nano‐silica (SiO2 NP) from waste product at the ZrC factory. Various techniques such as TEM, SEM‐EDX, ICP, XRD, FTIR, BET, and DLS were utilized to synthesize and characterize the silica nanoparticle. The results showed successful production of pure amorphous silica, with no discernible difference in purity percentage between samples prepared with or without acidic pre‐treatment. It was found that the leaching temperature, process time, and reactant ratio all played a role in the production of nano‐silica. The ideal leaching temperature was determined to be 368 K, with an optimal process time of 2 h. The weight ratio of WPZF/NaOH that yielded the highest percentage of silica extraction was 9 : 10. Additionally, at pH 7, the nano‐silica exhibited the best specific surface area (BET) of 472.51 m2/g. The average size of the spherical nano‐silica, as determined by DLS, was approximately 38 nm. Furthermore, the produced nano‐silica was found to be an effective catalyst for the treatment of methylene blue (MB). MB could be degraded by more than 99 % of the initial concertation (10 mg/L) in the presence of NaBH4 within 16 min and rate constant of the catalytic reduction achieved as 0.134 min−1. These findings demonstrate the potential of amorphous nano‐silica as a valuable resource in various applications. [ABSTRACT FROM AUTHOR]

In order to enhance the oil–water separation properties of polyurethane foam (PFU), hydrophobic silica nanoparticles (H‐SiO2 NPs) were firstly prepared by incorporating long alkyl chains into silica nanoparticles, and then, it was combined with PFU by in situ loading to fabricate a hydrophobic PFU (H‐SiO2 NPs/PUF). When the loading amount of H‐SiO2 NPs was 10%, the water contact angle of the modified foam H‐SiO2 NPs/PUF‐10 reached 147 ± 1°, which proved it was highly hydrophobic. The elongation at break of the foam was increased by 202%, which indicated that it had better resilience and recyclability. In addition, the total pore area and porosity were increased to 16.24 m2/g and 88.43% from 5.46 m2/g and 2.11%, which provided more storage space for adsorption. The oil–water separation experiment showed that the adsorption capacity for most light oils was 11–13 g/g, and that for dichloromethane was as high as 40.5 g/g. After 10 adsorption–desorption cycles, the adsorption capacity only decreased from 15.6 to 14.5 g/g, which was still 93% of the initial adsorption capacity. H‐SiO2 NPs/PUF represents good adsorption capacity, recyclability, and recyclability, so it as a carrier has a potential application in the treatment of marine oil spills. [ABSTRACT FROM AUTHOR]

Adequate topical hemostatic dressings are required as first-line approach for reduction of uncontrolled hemorrhage, a leading cause of mortalities. Platelets play a major role during blood clotting to prevent hemorrhage during injuries. Here, we demonstrate the mechanisms activated through protease activating receptor 1 (PAR1), a platelet membrane protein in response to a porous composite xerogel dressing incorporating SiNPs (size 122 ± 10 nm) and calcium (2.5 mM), characterized by scanning electron microscopy-energy dispersive x-ray spectroscopy and Fourier transform infrared spectroscopy. The composite displayed 13.9-fold improved blood clotting index in comparison to commercial dressing. The composite displayed increased platelet aggregation due to development of well-formed pseudopodia as compared to bare xerogel, SFLLRN (a thrombin mimic), adenosine di-phosphate (a platelet activator), and heparin (a thrombin inhibitor). Further, PAR1 gene was significantly upregulated in model A549 epithelial cell line (1.2-fold) and human platelets (1.4-fold). The composite enhanced calcium release and its extrusion in A549 cells. Upregulation of PAR1 on the platelet surface and calcium release are crucial for platelet shape change and aggregation. The data indicate that xerogel composite containing SiNPs and calcium enhanced blood clotting through activation of PAR1. Such dressings can provide a potential hemostatic solution to reduce blood loss, disability, and mortality during surgery and trauma care. [ABSTRACT FROM AUTHOR]

This study explores the modification of pore structures in porous silica materials synthesized using sodium silicate and waste gelatin, under varying silica‐to‐gelatin ratios. At ratios of 1.0–1.5, bimodal porous silica with mesopores and macropores emerged due to spaces between silica nanoparticles and clusters, following gelatin elimination. The study further evaluated the obtained bimodal porous silica as polyethyleneimine (PEI) supports for CO2 capture, alongside PEI‐loaded unimodal porous silica and hollow silica sphere for comparison. Notably, the PEI‐loaded bimodal silica showcased superior CO2 uptake, achieving 145.6 mg g−1 at 90 °C. Transmission electron microscopy (TEM) revealed PEI′s uniform distribution within the pores of bimodal silica, unlike the excessive surface layering seen in unimodal silica. Conversely, PEI completely filled the hollow porous silica's interior, extending gas molecule diffusion distance. All sorbents displayed nearly constant CO2 adsorption across 20 cycles, demonstrating outstanding stability. Notably, the bimodal porous silica displayed a negligible capacity loss, underscoring its robust performance. [ABSTRACT FROM AUTHOR]

This work reports the fabrication of a large‐sized hydrogel sheet with enhanced mechanical and adhesive properties. The fabrication involves the introduction of carboxymethyl‐modified cellulose nanofibers (m‐CNFs) and solid silica nanoparticles (SSNs) as physical cross‐linkers into acrylic acid monomer (AA), followed by bar coating and photopolymerization. The addition of the nanomaterials to the monomer solution renders it viscous, enabling the fabrication of A4‐sized hydrogel sheets with uniform thickness and enhanced mechanical and adhesive properties. Interestingly, the combined incorporation of both the nanomaterials generates a synergistic effect to improve the properties much more, which results from the hierarchical rupture of the multiple hydrogen‐bonded interactions among the poly(acrylic acid) (PAA) matrix, m‐CNFs, and SSNs. Under optimal conditions, the hydrogel sheet incorporated with the dual crosslinkers exhibits a sevenfold higher toughness and a sixfold increased peel strength than plain PAA, together with good biocompatibility. Furthermore, when mesoporous silica nanoparticles (MSNs) with active agent loading into their pores are incorporated instead of SSNs, the active agent can be released from the hydrogel sheet in a sustained or temperature‐sensitive manner, indicating that the system is potentially applicable to transdermal drug delivery system with no additional adhesive. [ABSTRACT FROM AUTHOR]

Styrene/methyl methacrylate (St/MMA) copolymer‐silica nanocomposite foams were prepared using supercritical CO2 as blowing agent, and the relationships between their cellular microstructure and mechanical properties were investigated. The effects of nanosilica content, size, and surface chemistry on the foam's microstructure and properties were examined. Dispersion and distribution of silica nanoparticles with different surface chemistry in St/MMA copolymer nanocomposites were discussed. To determine the most suitable copolymer composition for incorporating silica nanoparticles, some operating conditions such as temperature and pressure were primarily examined to study their effects on the microstructure of resulting foams. In compressive mechanical properties of final foams, a considerably high value was obtained for the compressive strength of the foams of up to 9.5 MPa. The prepared low‐density (below 0.2 g/cm3) St/MMA copolymer microcellular foams can be used in green lost foam iron casting processes. Highlights: Styrene/methyl methacrylate copolymer‐silica nanocomposite foams were prepared via supercritical CO2.Foams' cell size was changed by changing silica nanoparticle surface chemistry and size.The uniform cellular microstructure was achieved by nanosilica size increment.Increasing nanoparticle size improved the foam's mechanical properties.Low‐density foams were achieved for potential application in lost foam casting. [ABSTRACT FROM AUTHOR]

It is still a big challenge to prepare superhydrophobic anti-icing coatings with long freeze delay performance and high durability. In this work, in different with conventional flexible porous coating, we prepared an asymmetric coating with hierarchical pocket structure by a facile hot-pressing/salt-leaching (BHS) method on a polyacrylate vitrimer polymer with mellability. The asymmetric architecture endowed porous coating with low density and high adhesion strength. The in-situ growth of silica nanoparticles in above porous coating and surface modification generated a superhydrophobic hierarchical pocket structure. As a result, the freezing delay time was drastically increased to 14,400 s at -10°C. Furthermore, owing to hierarchical pocket structure, the coating could maintain its superhydrophobicity and anti-icing performance under water flow impacting at 10 kPa pressure, 30 cycles of sandpaper abrasion, 50 cycles of tape peeling, showing advantageous high durability. By employing the hierarchical porous coating on heat exchangers, the energy consumption was drastically reduced by 93%. [ABSTRACT FROM AUTHOR]

The fallen yellowish bamboo leaves around bamboo crops are always overlooked even though they contain high silica in their ash. Bamboo leaf valorization consequently has the potential to be a green process for synthesizing amorphous silica. Unfortunately, the optimum process parameters have not been widely disclosed. Hence, this study intends to optimize the synthesis of amorphous bio‐silica nanoparticles from bamboo leaves using Box–Behnken design (BBD). Bamboo leaves were initially washed with HCl, followed by combustion at 700°C, and then ash washing, extraction of silica with NaOH (sol–gel method), gelation, and drying. According to the results, optimum conditions occur under no acid washing of leaves, solvent‐to‐feed ratio = 5 mL/g, and extraction duration = 1.5 h. The optimum conditions give the highest purity (94.1 wt.%) and yield (42.33%) as well as the highest surface area (328.61 m2/g), smallest pore diameter (8.69 nm), and largest pore volume (0.71 cc/g) of bio‐silica nanoparticles. Furthermore, bio‐silica nanoparticles are amorphous, spherical‐shaped aggregates, and have a white powdered colour. [ABSTRACT FROM AUTHOR]

BACKGROUND: Rice, a pivotal global food staple, annually accumulates vast amounts of rice husks, resulting in substantial environmental impact. Exploiting the high silica content in rice husk, our research aimed to recycle this agricultural byproduct to synthesize mesoporous silica nanoparticles (rMSNs). These nanoparticles were further modified to evaluate their potential as effective carriers for cancer drug delivery. RESULTS: rMSNs showed high biocompatibility, large surface area and porous structure as MSNs, making them excellent drug carriers. Further modifications were applied to rMSNs, such as the incorporation of the lanthanides europium and gadolinium into rMSNs, making them fluorescent and magnetic for detection and tracking using confocal fluorescence microscopy and magnetic resonance imaging. Additionally, folic acid and aptamer AS1411 were conjugated with rMSNs to enhance the targeting of cancer cells. HeLa cells exhibited higher uptake of camptothecin (CPT)‐loaded rMSNs compared to normal fibroblast cells (L929). The linkage of disulfide bonds to rMSNs also allowed CPT to be carried by rMSNs and released intracellularly in the presence of the abundant reducing agent glutathione. The validation of rMSNs in vitro and in vivo proved their practical feasibility. CONCLUSION: Our findings indicate that low‐cost rMSNs, derived from recycled agricultural waste, can replace highly valuable MSNs. Functionalized rMSNs exhibit promising capabilities in transporting clinical drugs to specific aberrant tissues and offering dual‐targeting and dual‐imaging functionalities for enhanced cancer therapy. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

RNA interference (RNAi) is a powerful tool for understanding and manipulating signaling pathways in plant science, potentially facilitating the accelerated development of novel plant traits and crop yield improvement. The common strategy for delivering siRNA into intact plants using agrobacterium or viruses is complicated and time‐consuming, limiting the application of RNAi in plant research. Here, a novel delivery method based on mesoporous silica nanoparticles (MSNs) is reported, which allows for the efficient delivery of siRNA into mature plant leaves via topical application without the aid of mechanical forces, achieving transient gene knockdown with up to 98% silencing efficiency at the molecular level. In addition, this method is nontoxic to plant leaves, enabling the repeated delivery of siRNA for long‐term silencing. White spots and yellowing phenotypes are observed after spraying the MSN‐siRNA complex targeted at phytoene desaturase and magnesium chelatase genes. After high light treatment, photobleaching phenotypes are also observed by spraying MSNs‐siRNA targeted at genes into the Photosystem II repair cycle. Furthermore, the study demonstrated that MSNs can simultaneously silence multiple genes. The results suggest that MSN‐mediated siRNA delivery is an effective tool for long‐term multi‐gene silencing, with great potential for application in plant functional genomic analyses and crop improvement. [ABSTRACT FROM AUTHOR]

The development of nucleic acid‐based drugs holds great promise for therapeutic applications, but their effective delivery into cells is hindered by poor cellular membrane permeability and inherent instability. To overcome these challenges, delivery vehicles are required to protect and deliver nucleic acids efficiently. Silica nanoparticles (SiNPs) have emerged as promising nanovectors and recently bioregulators for gene delivery due to their unique advantages. In this review, a summary of recent advancements in the design of SiNPs for nucleic acid delivery and their applications is provided, mainly according to the specific type of nucleic acids. First, the structural characteristics and working mechanisms of various types of nucleic acids are introduced and classified according to their functions. Subsequently, for each nucleic acid type, the use of SiNPs for enhancing delivery performance and their biomedical applications are summarized. The tailored design of SiNPs for selected type of nucleic acid delivery will be highlighted considering the characteristics of nucleic acids. Lastly, the limitations in current research and personal perspectives on future directions in this field are presented. It is expected this opportune review will provide insights into a burgeoning research area for the development of next‐generation SiNP‐based nucleic acid delivery systems. [ABSTRACT FROM AUTHOR]