Search

We investigate water dynamics in mesoporous silica across partial crystallization by combining broadband dielectric spectroscopy (BDS), nuclear magnetic resonance (NMR), and molecular dynamics simulations (MDS). Exploiting the fact that not only BDS but also NMR field-cycling relaxometry and stimulated-echo experiments provide access to dynamical susceptibilities in broad frequency and temperature ranges, we study both the fully liquid state above the melting point Tm and the dynamics of coexisting water and ice phases below this temperature. It is found that partial crystallization leads to a change in the temperature dependence of rotational correlation times τ, which occurs in addition to previously reported dynamical crossovers of confined water and depends on the pore diameter. Furthermore, we observe that dynamical susceptibilities of water are strongly asymmetric in the fully liquid state, whereas they are much broader and nearly symmetric in the partially frozen state. Finally, water in the nonfreezable interfacial layer below Tm does not exhibit a much debated dynamical crossover at ∼220 K. We argue that its dynamics is governed by a static energy landscape, which results from the interaction with the bordering silica and ice surfaces and features a Gaussian-like barrier distribution. Consistently, our MDS analysis of the motional mechanism reveals a hopping motion of water in thin interfacial layers. The rotational correlation times of the confined ice phases follow Arrhenius laws. While the values of τ depend on the pore diameter, freezable water in various types of confinements and mixtures shows similar activation energies of Ea ≈ 0.43 eV. [ABSTRACT FROM AUTHOR]

We reported metallic ruthenium (Ru) nanoparticles loaded on amino modified dendritic mesoporous silica microspheres (Ru/NH2‐DMSMs) for ammonia decomposition to hydrogen. The sizes of the loaded Ru nanoparticles on carrier are 2–3 nm, providing rich active sites for ammonia decomposition reaction. As a result, the obtained Ru/NH2‐DMSMs‐5.1 can afford almost ~100 % ammonia decomposition at 550 °C, due to the unique mesoporous structure of DMSMs inhibiting the aggregation of active Ru nanoparticles and enhancing the mass transport of ammonia. [ABSTRACT FROM AUTHOR]

Breast cancer is one of the most prevalent malignancies, necessitating the exploration of more effective synergistic treatment strategies to overcome the limitations of conventional therapies. Chemodynamic therapy (CDT) is an innovative antitumor approach that can be combined with chemotherapy to achieve potent synergistic effects. Mesoporous silica nanomaterials (MSNs) are ideal drug delivery vehicles in cancer therapy due to their unique advantages. This study presents an effective and straightforward strategy to design an intelligent drug delivery system (DDS) activated by the tumor-specific weakly acidic microenvironment to achieve efficient cancer treatment. By incorporating the chemotherapeutic drug doxorubicin (DOX) and divalent iron (Fe2+) into the unique mesoporous channels of MSNs, we fabricated MSNs@Fe2+@DOX. Under weakly acidic pH conditions, the functional components Fe2+ and DOX of MSNs@Fe2+@DOX are gradually released at the tumor site. The released Fe2+ can then consume hydrogen peroxide (H2O2) in tumor cells, increasing the levels of reactive oxygen species (ROS) and lipid peroxides through the Fenton reaction, thereby inducing ferroptosis. The combination of DOX-induced apoptosis and ferroptosis results in further enhanced cancer treatment. In vitro and in vivo experiments demonstrated that MSNs@Fe2+@DOX had an excellent therapeutic effect on breast cancer cells and tumor-bearing nude mice. We anticipate that this study will provide a promising biotechnological platform for combined breast cancer treatment by inducing CDT and chemotherapy. [ABSTRACT FROM AUTHOR]

Background: The purpose of the study was to evaluate the effect of adding mesoporous silica with silver nanoparticles to conventional glass ionomer cements (GIC) on its, physical, chemical, mechanical properties and ion release analysis. Methods: Synthesized mesoporous silica with silver nanoparticles were added in 1, 3 and 5% by weight to the liquid component of GIC forming three experimental groups and compared with plain GIC as control group. Physical and chemical characterization were conducted using nano-computerized tomography (NanoCT) and Fourier transform infrared spectroscopy. Surface microhardness, water sorption and solubility were analyzed. Ion release was investigated using Inductive Coupled Plasma-Optical Emission Spectroscopy and High Performance Liquid Chromatography. Statistical analysis between different groups for the set parameters using parametric and non-parametric tests. The results were analysed using one way analysis of variance (p < 0.05). Results: Synthesized mesoporous silica with silver nanoparticles were of 7.28 ± 5.0 nm in diameter with a spherical morphology. NanoCT revealed less porosities for 3 wt %. Microhardness showed a statistically significant difference for 5 wt% at day 1 and 21 (p < 0.0001). Water sorption values decreased significantly on day 14 compared to day 7 for control, 1, 3 and 5 wt%. Control specimens showed highest concentration of fluoride release followed by 5, 3 and 1 wt%. Conclusion: Mesoporous silica with silver nanoparticles modified glass ionomer cements showed comparable microhardness to conventional GIC. Ion release was evident from the modified specimens. Silver remained within the GIC for atleast four weeks following incorporation. [ABSTRACT FROM AUTHOR]

Hydrogen production by methane catalytic decomposition is a promising method that also allows the formation of valuable carbon nanomaterials which can be utilized in transportation fuels, chemical synthesis, and fuel cell technology. In this study, bimetallic 3d transition metal (Ni, Fe, Co) catalysts supported on spherical mesoporous nanofibrous silica (KCC1) were successfully synthesized using a hydrothermal method followed by sono co-impregnation. The catalysts were evaluated for their performance in the catalytic decomposition of methane. Comprehensive characterization of the catalysts was conducted utilizing XRD, FTIR, SEM, TEM, STEM, XPS, H 2 -TPR, and BET techniques. XRD and TEM analyses confirmed the formation of Ni–Fe, Ni–Co, and Co–Fe bimetallic alloys on the nanofibrous silica without compromising its dendrimeric hierarchical structure. STEM HAADF imaging revealed a uniform dispersion of bimetallic nanoparticles within the spherical fibrous framework. Catalytic tests demonstrated that all bimetallic catalysts showed high stability and activity for methane cracking at 700 °C over 180 min of time on stream (TOS). Among them, Fe-based catalysts Ni–Fe/KCC1 and Co–Fe/KCC1 achieved the highest hydrogen yields of 80% and 60%, respectively. Methane conversion was 1.56 and 2.23 times higher in Ni–Fe/KCC1 compared to Co–Fe/KCC1 and Ni–Co/KCC1, respectively. Post-reaction characterization of the spent catalysts was performed using XRD, Raman spectroscopy, SEM, TEM, and TGA. XRD and Raman spectroscopy were used to evaluate the degree of graphitization and crystallinity in the carbon nanotubes (CNTs) produced on the catalysts, enabling a correlation with the catalyst properties. TEM examination was used to investigate the structural morphology and growth methods of the CNTs, including tip or base growth and chain-like or parallel-wall types. TGA results revealed that all bimetallic catalysts exhibited no amorphous carbon during methane cracking reaction. [Display omitted] • KCC1 framework enhances active site exposure and reactant/product diffusion. • Hierarchical dendritic layers pose a steric barrier, functioning as sintering-resistant support. • Highly dispersed bimetals obtained over KCC1 due to large accessible surface area. • KCC1 supported bimetallic (Ni, Fe, Co) alloys synergistically contributes to high stability. • Ni–Fe/KCC1 exhibited high catalytic activity with graphitized carbon structures. [ABSTRACT FROM AUTHOR]

Despite encouraging outcomes of the eight FDA approved drugs in lessening obesity burden, they have been associated with side effects caused by the lack of direct action on the adipose tissue. Therefore, a nanomedicine is reported that promotes the transformation of local fat‐storage white adipocytes, associated with obesity, into thermogenic adipocytes, indicative of enhanced metabolism, to both human cells and mice. This nanomedicine consisting of a lipid‐silica nanohybrid that allows accommodation of the natural supplement forskolin has resulted in successful browning of mature human adipocytes in vitro through upregulating thermogenesis biomarkers on mature human adipocytes and in vivo in mice tissue (achieving 400‐ and 80‐fold increases in UCP1 and Cox7A1, respectively), while significantly enhancing glucose uptake and lipolysis in an acute fashion and significantly preventing weight gain in high fat diet (60% HFD) mice compared to other treatments including liposomal medicine. [ABSTRACT FROM AUTHOR]

Ionic transport through porous membranes and porous materials has received enormous attention due to its importance to many applications. An innovative methodology is proposed to study ion diffusion and ion sieving through mesoporous silica membranes (shells). The mobility of fluorescently labeled core particles within a hollow porous shell, filled with an index‐matched electrolyte solution, is observed using confocal laser scanning microscopy. The core motion range, i.e., the area explored by the core within the hollow compartment, sensitively changed depending on the local ionic concentration. Monitoring transitions in the core motion range is a practical way to detect which ions can migrate through the shells and on what timescale. For instance, lithium and chloride ions easily diffused through the porous silica shells, resulting in a core motion range that changed relatively quickly upon change of the ion concentrations outside of the shell. However, the motion range changed significantly slower upon changing to a bigger cation (tetraoctylammonium ion). This proof of principle experiment can be explained by the Gibbs‐Donnan effect, revealing that the detection of core motion ranges is a good probe to measure both ion diffusion and ion sieving through porous membranes. [ABSTRACT FROM AUTHOR]

Neuromodulation technologies have gained considerable attention for their clinical potential in treating neurological disorders and advancing cognition research. However, traditional methods like electrical stimulation and optogenetics face technical and biological challenges that limit their therapeutic and research applications. A promising alternative, photoelectric neurostimulation, uses near‐infrared light to generate electrical pulses and thus enables stimulation of neuronal activity without genetic alterations. This study explores various design strategies to enhance photoelectric stimulation with minimally invasive, ultrasmall, untethered carbon electrodes. Employing a multiphoton laser as the near‐infrared (NIR) light source, benchtop experiments are conducted using a three‐electrode setup and chronopotentiometry to record photo‐stimulated voltage. In vivo evaluations utilize Thy1‐GCaMP6s mice with acutely implanted ultrasmall carbon electrodes. Results highlighted the beneficial effects of high duty‐cycle laser scanning and photovoltaic polymer interfaces on the photo‐stimulated voltages by the implanted electrode. Additionally, the promising potential of carbon‐based diamond electrodes are demonstrated for photoelectric stimulation and the application of photoelectric stimulation in precise chemical delivery by loading mesoporous silica nanoparticles (SNPs) co‐deposited with polyethylenedioxythiophene (PEDOT). Together, these findings on photoelectric stimulation utilizing ultrasmall carbon electrodes underscore its immense potential for advancing the next generation of neurostimulation technology. [ABSTRACT FROM AUTHOR]

Multi-aptamer recognition of breast cancer cells (MCF-7) is utilized to achieve high specificity. The method comprises two parts, aptamer-functionalized mesoporous silica nanoparticles (MSNs) loaded with dissimilar dyes (thymolphthalein or curcumin) as signal transducers and aptamer-modified magnetic beads (MBs) as capture agents, which worked together to detect MCF-7 cells sensitively and accurately. The results indicated that the aptasensor has a linear detection range of 100 to 4000 cells and a detection threshold of 10 cells/mL. The method had been successfully employed to detect breast cancer cells in real blood samples to distinguish between breast cancer patients and healthy individuals. In conclusion, the development of the multi-aptamer-based colorimetric sensor offered a novel method for the highly selective detection of MCF-7 cells, contributing to the accurate identification of breast cancer. [ABSTRACT FROM AUTHOR]

This document provides a summary of a collection of articles on porous nanomaterials. It discusses the importance and applications of these materials, such as catalysis, drug delivery, and energy storage. The document highlights recent advancements in the synthesis and characterization of porous nanomaterials, focusing on silica, carbon-based materials, metal-organic frameworks (MOFs), and zeolites. It also presents specific studies on the synthesis and application of these materials, as well as their potential in various industries. The summary acknowledges the contributions of the authors to the Special Issue and emphasizes the need for continued research in this field. [Extracted from the article]

Since early developments in the field of mesoporous materials, mesoporous silica has attracted large interest in drug delivery, as they display an ordered array of pores with diameters ranging from 2 to 50 nm, which can be loaded with drugs. Mesoporous silica dissolves at physiological pH, triggering the release of loaded drugs. Several studies have focused on determining the key factors that determine the biodistribution, biocompatibility, and toxicity both in vitro or in vivo. However, in vivo studies focused on the degradation of mesoporous silica materials are very scarce, despite its relevance for drug release. In this perspective, recent works addressing mesoporous materials degradation in the context of drug delivery are discussed, first from a physicochemical point of view, and secondly in in vivo settings, in animal models that are the closest conditions to the encountered when the mesoporous materials are administered to humans. Finally, further discussion about the future directions in the design of mesoporous nanomaterials for therapy and for the study of their biological fate are presented. [ABSTRACT FROM AUTHOR]

Background: Therapeutic approaches that combine conventional photodynamic therapy (PDT) with gas therapy (GT) to sensitize PDT are an attractive strategy, but the molecular structure design of the complex lacks effective guiding strategies. Results: Herein, we have developed a nanoplatforms Cy-NMNO@SiO2 based on mesoporous silica materials loaded NIR-activatable small-molecule fluorescent probe Cy-NMNO for the synergistic treatment of photodynamic therapy/gas therapy (PDT/GT) in antibacterial and skin cancer. The theoretical calculation results showed that the low dissociation of N-NO in Cy-NMNO enabled it to dissociate effectively under NIR light irradiation, which is conducive to produce Cy and NO. Cy showed better 1O2 generation performance than Cy-NMNO. The cytotoxicity of Cy-NMNO obtained via the synergistic effect of GT and PDT synergistically enhances the effect of photodynamic therapy, thus achieving more effective tumor treatment and sterilization than conventional PDT. Moreover, the nanoplatforms Cy-NMNO@SiO2 realized efficient drug loading and drug delivery. Conclusions: This work not only offers a promising approach for PDT-GT synergistic drug delivery system, but also provides a valuable reference for the design of its drug molecules. [ABSTRACT FROM AUTHOR]

• Four candesartan cilexetil-loaded mesoporous silica dispersions were prepared through solvent immersion. • Dissolution in vitro of four formulations were evaluated using flow-through cell dissolution method. • Pore size and surface area of carriers played key roles in drug loading and release. • CC-XDP 3150 exhibited a 1.88-fold larger release of CC as compared to crystalline drug. • The relative bioavailability of CC-XDP3150 in rats was enhanced 326 % in comparison with CC. Candesartan cilexetil (CC) is one of well-tolerated antihypertensive drugs, while its poor solubility and low bioavailability limit its use. Herein, two mesoporous silica (Syloid XDP 3150 and Syloid AL-1 FP) and the corresponding amino-modified products (N-XDP 3150 and N-AL-1 FP) have been selected as the carriers of Candesartan cilexetil to prepare solid dispersion through solvent immersion, and characterized through using powder X-ray diffraction analysis, infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, and solid-state nuclear magnetic resonance spectroscopy, etc. The state of CC changed from crystalline to amorphous after loading onto the silica carriers, in which no interactions between CC and silica existed. Then, the dissolution behaviors in vitro were studied through using flow-through cell dissolution method. CC-XDP 3150 sample exhibited the most extensive dissolution, and the cumulative release of CC from it was 1.88-fold larger than that of CC. Moreover, the pharmacokinetic results in rats revealed that the relative bioavailability of CC-XDP 3150 and CC-N-XDP 3150 solid dispersions were estimated to be 326 % % and 238 % % in comparison with CC, respectively. Clearly, pore size, pore volume, and surface properties of silica carrier have remarkable effect on loading, dissolution and bioavailability of CC. In brief, this work will provide valuable information in construction of mesoporous silica-based delivery system toward poorly water-soluble drugs. [Display omitted] [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) proves highly effective in addressing melanoma, and its synergy with targeted therapy offers a promising avenue in tumor treatment. However, the therapeutic outcome is largely impeded by the challenge of current photosensitizers and targeted drugs in reaching deep tumor tissues. Herein, a dually‐layered "microneedle rocket" termed PcNP/TRA‐HA‐Tyr/CLG‐MN is designed. The upper layer of the microneedle (MN) is composed of photodynamically active mesoporous silica nanoparticles, featuring photosensitizers covalently bonded to them. Within the mesopores of these nanoparticles lies trametinib (TRA), a compound that specifically targets the hyperactive MEK pathway present in melanoma cells. The lower layer is composed of an enzyme‐mediated hyaluronic acid‐tyramine hydrogel (HA‐Tyr/CLG) with collagenase (CLG), serving as rocket thrusters for remodeling the extracellular matrix (ECM) in tumor microenvironment. Among the three types of MNs prepared, the PcNP/TRA‐HA‐Tyr(II)/CLG‐MN exhibits the deepest penetration in tumor tissues and the longest retention time in vivo. Notably, the administrations of PcNP/TRA‐HA‐Tyr(II)/CLG‐MN alongside light irradiation significantly suppress the growth of A375‐xenografted tumors in mice. Together, the strategy of combining mesoporous silica nanoparticles, enzymatically cross‐linked hydrogels and CLG‐mediated ECM remodeling enables deep drug penetration and efficacious combination treatment against melanoma, showcasing significant potential in the realm of cancer nanomedicine. [ABSTRACT FROM AUTHOR]

In this study, poly (ethylene-co-vinyl acetate)/mesoporous silica EVA/SBA-15 nanocomposites, containing 0.5, 1.5, and 2.5 wt% of unfunctionalized and functionalized SBA-15 were prepared by melt blending in an internal mixer. Mesoporous silica was synthesized through the sol-gel method and modified by hexadecyltrimethoxysilane (HDTMS). Several characterizations were performed; including Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), mechanical properties, dynamic mechanical analysis (DMA), and dielectric study to characterize the physicochemical properties of elaborated materials. The results revealed the successful synthesis and functionalization of mesoporous silica, as confirmed by the FTIR and SEM. The crystallinity of the nanocomposites decreased and the elastic modulus increased with the incorporation of the mesoporous silica. Measurement of tensile properties shows that the tensile strength of the nanocomposite content of 1.5 wt% F-SBA-15 is 17.2% is higher as compared to pure EVA. DMA analysis validates the improvement in mechanical properties of the EVA/SBA-15 samples. SEM images displayed well-dispersed F-SBA-15 nanoparticles and enhanced interfacial adhesion between the phases. TGA indicates the enhancement of the thermal stability of nanocomposites as compared with the pure EVA matrix. The surface functionalization presented an approach to preparing nanocomposites with enhanced thermal stability and a low dielectric constant. [ABSTRACT FROM AUTHOR]

Fischer-Tropsch synthesis (FTS) converts syngas into multi-carbon products, whose distribution is highly dependent on the catalyst structure. Here, nano-iron catalysts with different silica supports were prepared, and their activities and durability for Fischer-Tropsch to olefins (FTO) process were investigated. Fe/KCC-1 demonstrated the best FTO catalytic selectivity of 25.0% for C2–4= and an olefin-to-paraffin ratio of 1.68. Its open pore structure allowed primary olefins to escape quickly from the catalyst surface, lowering the probability for secondary reactions. However, its durability was lower than Fe/SBA-15 due to coke formation, pore structure collapse and Fe particle agglomeration. The thermal stability of SBA-15 resulted in its better durability, and the encapsulated Fe particles inside the cylindrical mesopores also allowed better resistance to sintering. However, the less open structure of Fe/SBA-15 led to longer residence time for the primary olefins and increased possibility for secondary reactions, causing undesired chain growth. [ABSTRACT FROM AUTHOR]

Recent advancements in cancer treatment have underscored the inadequacy of conventional monotherapies in addressing complex malignant tumors. Consequently, there is a growing interest in synergistic therapies capable of overcoming the limitations of monotherapies, leading to more personalized and effective approaches. Among these, the combination of photothermal therapy (PTT) and chemotherapy has emerged as a promising avenue for tumor management. In this study, we present a novel approach utilizing thermoresponsive mesoporous silica nanoparticles (MSN) as a delivery system for the chemotherapeutic drug doxorubicin. By incorporating photothermal agent copper sulfide (CuS) nanoparticles into the MSN, the resulting composite material exhibits potent photothermal properties. Furthermore, the integration of an upper critical solution temperature (UCST) polymer within the silica outer layer serves as a "gatekeeper", enabling precise control over drug release kinetics. This innovative nanomaterial effectively merges thermoresponsive behavior with PTT, thereby minimizing the collateral damage associated with traditional chemotherapy on healthy tissues. Moreover, in both in vitro studies using mouse breast carcinoma cells (4 T1) and in vivo experiments utilizing a 4 T1 tumor-bearing mouse model, our nanomaterials demonstrated synergistic effects, enhancing the anti-tumor efficacy of combined PTT and chemotherapy. With its remarkable photothermal conversion efficiency, robust stability, and biocompatibility, the UCST-responsive nanoplatform holds immense potential for clinical applications. Upon exposure to NIR laser irradiation, CuS nanoparticles induce photothermal conversion, elevating the temperature to the UCST and triggering the phase transition of the external polymer from hydrophobic to hydrophilic states. This controlled response facilitates the release of Dox from the pores of MSN. The resulting nanocarrier, featuring a synergistic combination of PTT and chemotherapy, demonstrated exceptional anti-tumor efficacy at both cellular and animal levels. [Display omitted] • A cascade response mechanism utilizing photothermal and temperature-responsive nanoplatform has been achieved. • The outer layer of UCST-type polymer on C@M@P acts as a "gatekeeper" to enable precise control over drug release kinetics. • Upon NIR laser irradiation, CuS induce photothermal conversion, triggering the phase transition of the external polymer. [ABSTRACT FROM AUTHOR]

This study investigates the development of magnetic mesoporous silica functionalized with amine groups (MMS-NH2) for its combined capability in heavy metal removal and bacterial inhibition, aiming to address critical water treatment challenges. MMS-NH2 was successfully synthesized and meticulously characterized using various techniques: Field Emission Scanning Electron Microscopy (FESEM) for morphology, Brunauer-Emmett-Teller (BET) analysis for surface area and porosity, X-ray diffraction (XRD) for crystallinity, Fourier Transform Infrared (FTIR) spectroscopy for functional group identification, Thermogravimetric Analysis (TGA) for thermal stability, and Vibrating Sample Magnetometry (VSM) for magnetic properties. The removal efficiency of five common heavy metals (Pb(II), Cu(II), Ni(II), Hg(II), and Cd(II)) from water using MMS-NH2 was investigated. influence of adsorbent dosage (0.05–2 g.L− 1), solution pH (2–10), and initial metal ion concentration (50–200 mg.L− 1) on the adsorption process was systematically investigated, revealing optimal conditions for each metal ion. Isotherm models (Langmuir, Freundlich, Dubinin-Radushkevich) were employed to understand the adsorption mechanism, indicating a favorable and monolayer chemisorption process. Kinetic models (pseudo-first-order, pseudo-second-order, Elovich) were used to study the adsorption kinetics, suggesting a rapid and chemisorption-controlled mechanism. Thermodynamic parameters (ΔG°, ΔH°, and ΔS°) were calculated, confirming the spontaneous and exothermic nature of the adsorption process. Furthermore, the antibacterial activity of MMS-NH2 was investigated against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. The results demonstrated significant inhibition rates, ranging from 70 to 90%, for both bacterial strains. The amine group functionalization is attributed to enhancing both heavy metal adsorption capacity and bacterial inhibition. [ABSTRACT FROM AUTHOR]

[Display omitted] Here, we report the preparation of a novel Janus nanoparticle with opposite Ir and mesoporous silica nanoparticles through a partial surface masking with toposelective modification method. This nanomaterial was employed to construct an enzyme-powered nanomachine with self-propulsion properties for on-command delivery. The cargo-loaded nanoparticle was provided with a pH-sensitive gate and unit control at the mesoporous face by first attaching boronic acid residues and further immobilization of glucose oxidase through reversible boronic acid esters with the carbohydrate residues of the glycoenzyme. Addition of glucose leads to the enzymatic production of H 2 O 2 and gluconic acid, being the first compound catalytically decomposed at the Ir nanoparticle face producing O 2 and causing the nanomachine propulsion. Gluconic acid leads to a pH reduction at the nanomachine microenvironment causing the disruption of the gating mechanism with the subsequent cargo release. This work demonstrates that enzyme-mediated self-propulsion improved release efficiency being this nanomotor successfully employed for the smart release of Doxorubicin in HeLa cancer cells. [ABSTRACT FROM AUTHOR]

In this work, a mesoporous silica (SBA-15) was synthesized using a hydrothermal method and the surface of the SBA-15 was further modified by utilizing the organosilane compound γ- aminopropyltriethoxysilane(APTES); FT-IR testing confirmed the successful grafting of these organic groups onto the surface of the SBA-15, the result being the AP-S. Composite films were subsequently prepared through a casting method, with SBA-15 and AP-S serving as the inorganic filler particles, and PVA acting as the matrix material. These films were characterized by tensile texts, dynamic mechanical analysis, scanning electron microscopy, and dielectric measurements. The results showed that the tensile modulus, loss modulus and dielectric properties of the modified AP-S/PVA composite films were improved compared with those of SBA-15/PVA, with the tensile strength being the largest at 145.25 MPa when the AP-S content was 2%. This result combined with the SEM analysis, shows that the incorporation of SBA-15 modified by APTES into PVA films can effectively improve the dispersion of SBA-15 in the PVA films, which can also explain the performance enhancement. [ABSTRACT FROM AUTHOR]

Myocardial infarction accompanied by diabetes mellitus is accepted as the most serious type of coronary heart disease, and among the current treatment strategies, the precise delivery of protective drugs for inhibiting cardiomyocyte apoptosis is still a challenge. In this study, we developed a biodegradable nanoparticles‐based delivery system with excellent macrophage escape, cardiac targeting, and drug release properties to achieve targeted therapy of myocardial infarction. Specifically, a copolymer of p(DMA–MPC–CD) combining self‐adhesion, hydration lubrication, and targeting peptide binding site was successfully prepared by free radical copolymerization, and it was self‐assembled on the surface of melatonin‐loaded dendritic mesoporous silica nanoparticles (bMSNs) following the integration of adamantane‐modified cardiac homing peptide (CHP) based on supramolecular host–guest interaction. Importantly, a hydration layer formed around the zwitterionic phosphorylcholine groups of the multifunctional nanoparticles, which was confirmed by the enhancement in hydration lubrication and reduction in coefficient of friction, prevented the nanoparticles from phagocytosis by the macrophages. The in vivo bioluminescence imaging test indicated that the nanoparticles were endowed with satisfied cardiac targeting capability, and the in vivo mice study demonstrated that the intravenous injection of drug‐loaded nanoparticles (namely bMSNs–Mel@PDMC–CHP) effectively reduced cardiomyocyte apoptosis, alleviated myocardial interstitial fibrosis, and enhanced cardiac function. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work reports the amine and mercapto bi-functionalized mesoporous silica MCM-41 for heavy metal ions removal from aqueous solutions. XRD, FTIR and N2 adsorption–desorption analyses confirmed that a series of bi-functionalized mesoporous silica MCM-41 with huge specific surface area were successfully obtained. In aqueous solution, the adsorption performance were evaluated by the adsorption of Zn(II), Cu(II), Cr(III) and Pb(II). The obtained results indicate that synthesis process has no significant influence on the structure and the existence of functional group resulted in outstanding adsorption capacity. The methodology of pre-hydrolysis was one effective treatment for grafting useful functional group on to mesoporous silica. The adsorption reactions for the adsorption of heavy metal ions by bi-functionalized silica-based mesoporous materials were spontaneous adsorption processes over the range of experimental temperatures. The adsorption isotherm is consistent with the Freundlich adsorption isotherms model. The Freundlich parameters KF and n indicated favorable adsorption. The adsorption kinetics of heavy metalions over these bi-functionalized mesoporous silica could be well described by pseudo-second-order models. Therefore, this bi-functionalized mesoporous material has promise for the removal and recovery of heavy metal ions from water. [ABSTRACT FROM AUTHOR]

Background: Bufalin (BA) is a potent traditional Chinese medicine derived from toad venom. It has shown significant antitumor activity, but its use is limited by cardiotoxicity, which necessitates innovative delivery methods, such as rod-shaped mesoporous silica nanoparticles (rMSNs). rMSNs have been extensively employed for reducing drug toxicity and for controlled or targeted drug delivery in tumor therapy. However, their potential in delivering BA has not been completely elucidated. Therefore, in this study, BA-loaded rMSNs (BA-rMSNs) were developed to investigate their potential and mechanism in impairing colon cancer cells. Methods: rMSNs were developed via the sol‒gel method. Drug encapsulation efficiency and loading capacity were determined to investigate the advantages of the rMSN in loading BA. The antiproliferative activities of the BA-rMSNs were investigated via 5-ethynyl-2'-deoxyuridine and CCK-8. To evaluate cell death, Annexin V-APC/PI apoptotic and calcein-AM/PI double staining were performed. Western blotting, oil red O staining, and Nile red solution were employed to determine the ability of BA-rMSNs to regulate lipophagy. Results: The diameter of the BA-rMSNs was approximately 60 nm. In vitro studies demonstrated that BA-rMSNs markedly inhibited HCT 116 and HT-29 cell proliferation and induced cell death. In vivo studies revealed that BA-rMSNs reduced BA-mediated cardiotoxicity and enhanced BA tumor targeting. Mechanistic studies revealed that BA-rMSNs blocked lipophagy. Conclusions: rMSNs reduced BA-mediated cardiotoxicity and impaired the growth of colon cancer cells. Mechanistically, antitumor activity depends on lipophagy. [ABSTRACT FROM AUTHOR]

Paraptosis is a non‐apoptotic and caspase‐independent programmed cell death that can trigger immunogenic cell death (ICD) in tumor cells, representing a potent tactic to overcome immune tolerance to apoptosis. Here, this study demonstrates the construction of a dual‐responsive nanoreactor (MCGDH) to achieve paraptosis‐mediated ICD for chemo‐immunotherapy. Specifically, by doping Cu2+ into glutathione (GSH)‐responsive dendritic mesoporous silica nanoparticles, the platform (CGDMSN) is endowed with partial acid‐sensitivity. After loaded with 8‐hydroxyquinoline (8‐HQ), cell membrane fragments are coated onto the ammoniated CGDMSN surface to construct MCGDH. Upon internalization by tumor cells, the release of Cu2+ and 8‐HQ from MCGDH in response to the acidic pH and high concentration of GSH in the tumor microenvironment stimulates in situ generation of Cu(8‐HQ)2, inducing tumor cells paraptosis at a low copper dose. Moreover, MCGDH‐mediated paraptosis amplifies the immunogenicity of tumor cells, facilitating antigen presentation to dendritic cells and activating CD8+/CD4+ T cells immune responses. Furthermore, the combination of MCGDH and anti‐PD‐1 antibodies (αPD‐1) promotes the systemic anti‐tumor immune responses and long‐term immunological effect to vastly inhibit the primary/distant tumor growth and prevent tumor metastasis. This GSH/pH dual‐responsive nanoreactor serves as a selective platform for accelerating the development of chemo‐immunotherapy. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance of precious metal gold nanorods can be tuned by controlling the aspect ratio, and they find widespread applications in biotechnology, imaging, sensing, optoelectronics, photonics, and catalysis. Here, a method is proposed for the controlled etching of gold nanorods within mesoporous silica shells by using a certain concentration of H2O2 at room temperature. In the experiments, the amount of HCl is varied to adjust the acidity and/or change the amount of H2O2 to control the speed of corrosion, achieving controllable adjustment of the aspect ratio of the gold nanorods. The extinction spectra show that under the action of H2O2 and HCl, the longitudinal plasmonic resonance of the gold nanorods shifted to shorter wavelengths, and the intensity of the longitudinal plasmonic resonance decreased. The more hydrochloric acid or hydrogen peroxide added, the faster the corrosion rate of the gold nanorods, and the faster the blue shift of the longitudinal plasmonic resonance. In addition, the intensity of the extinction spectra at 320 nm increased linearly versus time, which can also be used to monitor the etching process. By corroding gold nanorods to control the plasmonic resonances, gold nanorods can find broader applications. [ABSTRACT FROM AUTHOR]

A highly stable single-excitation double-emission long afterglow phosphor is reported for use in dynamic anti-counterfeiting. The red phosphor ZnCaGa2O4:Cr3+ was introduced into the pores of mesoporous silica nanoparticles (MSNs) by in situ polymerization, and the green phosphor SrAl2O4:Eu2+,Dy3+, when embedded in silicon dioxide, provided a long-lasting waterproof afterglow. The anti-counterfeiting material emits red light under UV excitation at 254 nm and, on stopping the excitation, produces a long-lasting green afterglow. Traditional anti-counterfeiting methods often require the use of a variety of different excitation light sources to achieve different luminous effects, while this innovative material requires only one excitation light source to achieve red light and green afterglow, and greatly simplifies the preparation process of anti-counterfeiting materials. In addition, this material is highly stable and can maintain its luminescent properties for a long time under various environmental conditions and is not prone to fading or degradation. Single-excitation dual-emission long afterglow anti-counterfeiting materials can effectively prevent products from being counterfeited, and this study provides new ideas and methods for technological innovation in the field of anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Intracellular bacterial (ICB) infection is one of the most life‐threatening cases of drug resistance, and photodynamic therapy (PDT) is challenged by limited light penetration into tissues and unspecific toxicity to host cells. Herein, theranostic nanoparticles (NPs) are developed to facilitate on‐demand activation of photosensitizers inside ICBs and persistent PDT of deep‐tissue ICB infections. Mechanoluminescent SrAl2O4:Eu2+ and persistence luminescent CaS:Eu2+ are sequentially deposited on mesoporous silica to prepare mSC, followed by encapsulation by bacterial membranes with loaded nitroreductase (NTR)‐activatable methylene blue (nMB) to obtain mSC‐nMB@BM NPs. The fluorescence quenching of nMB with mSC offers few cytotoxicities even under ultrasonication, and bacterial membrane coatings mediate the specific NP internalization into ICB‐infected macrophages. Bacterial pore‐forming toxins trigger nMB release from NPs, and intrabacterial NTR rejuvenates methylene blue probes from nMB for real‐time imaging of ICB infections. Ultrasonication of NPs continuously excites the rejuvenated methylene blue to generate reactive oxidative species and reduce viable ICBs by 3.54 log magnitude folds. NP treatment on ICB‐infected mice exhibits full survival and restores viscera functions without any pathological abnormality. Therefore, this concise NP design demonstrates capabilities of bacterial membrane‐mediated specific internalization, bacterial toxin‐triggered release and intrabacterial NTR‐rejuvenation of fluorescent probes, and persistent internal light‐illumination for ICB theranostics. [ABSTRACT FROM AUTHOR]

Selective oxidation is one of the primary methods used to synthesize high‐value‐added oxygen‐containing organic compounds from alkenes. In particular, the selective oxidation of natural cinnamaldehyde has gained prominence as one of the main routes to produce natural benzaldehyde, which is in short supply in the global spice market. In this study, FeSBA catalysts were synthesized by supporting Fe2O3 onto the surface of spherical SBA‐15 using pore‐induced deposition for the selective oxidation of cinnamaldehyde to benzaldehyde. The Fe2O3 supporting increased the specific surface area of SBA‐15 by approximately eightfold and significantly improved the utilization efficiency of the reaction sites on Fe2O3. Additionally, the formation of Fe−O−Si bonds by Fe2O3 and SBA‐15 promoted the generation of weak‐acidic sites on the catalyst surface, significantly increasing the oxygen‐physisorption capacity of Fe2O3. Furthermore, quenching experiments confirmed the generation of significant amounts of O2− and singlet‐oxygen species on the FeSBA surface. Theoretical calculations confirmed that the physisorption and chemisorption of cinnamaldehyde and oxygen, respectively, on the FeSBA surface promoted the formation of a tetrameric intermediate. These results contribute significantly to research on the selective oxidation theory of α,β‐unsaturated aldehydes to aldehydes using oxygen and could guide future studies aimed at elucidating and improving the process. [ABSTRACT FROM AUTHOR]

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]

Development of novel abrasive systems with functional activities and physicochemical properties are of great significance in the reactive oxygen species (ROS)-enhanced chemical mechanical polishing. In this work, Ce single-doped and Ce/Cu co-doped dendritic mesoporous silica nanoparticles (DMSNs), namely Ce−DMSNs and Ce/Cu−DMSNs, were produced via a simple impregnation and thermolysis procedure. The Ce and/or Cu species involved in DMSNs frameworks were characterized through X-ray diffractometry, infrared spectroscopy, scanning electron microscopy, energy dispersive spectrometry, transmission electron microscopy, X-ray photoelectron spectroscopy, and nitrogen adsorption/desorption techniques. We report the evolution of surface morphology and roughness, defects, peak-to-valley data, image surface area difference, and material removal efficiency during ROS-enhanced polishing experiments toward silica materials. All the pure, Ce single-doped, and Ce/Cu co-doped DMSNs abrasive systems offered nearly defect-free surfaces with close-to-atom scale roughness. It might be attributed to the "springlike effect" and "soft polishing/abrasion", possibly originating from the low-modulus DMSNs carriers. Among these abrasives, the Ce/Cu co-doped DMSNs systems achieved an evident improvement in removal efficiency, especially under ultraviolet irradiation-assisted polishing conditions. The coexisted Ce(Ⅲ)/Ce(Ⅳ) and Cu(Ⅰ)/Cu(Ⅱ) couples might be responsible for the effective production of ROS in photocatalysis and Fenton-like processes, thereby contributing to the Si–OH and Ce(Ⅲ)−O–Si bonding formations. The role of the developed Ce/Cu co-doped DMSNs abrasive systems in ROS-enhanced polishing processes was discussed. [ABSTRACT FROM AUTHOR]

AbstractSilica nanoparticles are increasingly considered for drug delivery applications. These applications require an understanding of their biocompatibility, including their interactions with the immune system. However, systematic studies for silica nanoparticle immunological safety profiles are lacking. To fill this gap, we conducted an in vitro study investigating various aspects of silica nanoparticles’ interactions with blood and immune cells. Four types of silica nanoparticles with variations in size and porosity were studied. These included nonporous Stöber silica nanoparticles with average diameters of approximately 50 and 100 nm (SNP50 and SNP100), mesoporous silica nanoparticles of approximately 100 nm (Meso100), and hollow mesoporous silica nanoparticles of approximately 100 nm (HMSNP100) in diameter, respectively. The hematological compatibility was assessed using hemolysis, complement activation, platelet aggregation, and plasma coagulation assays. The effects of nanoparticles on immune cell function were studied using in vitro phagocytosis, chemotaxis, natural killer cell cytotoxicity, leukocyte proliferation, human lymphocyte activation, colony-forming unit granulocyte-macrophage, and leukocyte procoagulant activity assays. The in vitro findings suggest that at high concentrations, corresponding to the in vivo human dose of 40 mg/kg, silica nanoparticles demonstrated an array of immunotoxic effects that depended on their physicochemical properties. However, all types of silica nanoparticles studied were not immunotoxic at concentrations corresponding to lower doses (≤ 8 mg/kg) comparable to that of nanocarriers in other nanomedicines currently used in the clinic. These findings are promising for using silica nanoparticles for the systemic delivery of bioactive and imaging agents. [ABSTRACT FROM AUTHOR]

Personal radiative cooling fabrics are a promising zero‐energy solution for creating a cool and comfortable microclimate for outdoor crowds. Despite significant progress, achieving efficient radiative cooling under some extreme situations, such as thermal shock and intensive physical activity, remains a challenge. Herein, a bioinspired metafabric with a dual‐gradient Janus design is reported for personal radiative and evaporative cooling. The hierarchical fiber structure allows for an excellent solar reflectance of 99.4% and mid‐infrared emittance of 0.94, inducing a skin temperature drop of 17.8 °C under intense sunlight. Mesoporous silica nanoparticles fixed in the fibrous network can store evaporative cooling capacity by atmospheric moisture‐absorption in the mild and humid nighttime and release such cooling capacity by moisture‐desorption in the hot daytime, providing an additional skin temperature drop of 2.5 °C. Dual‐gradient Janus design endows the metafabric with an outstanding sweat‐wicking effect and high‐performance sweat evaporative cooling capacity. In the steady‐state evaporation tests, a maximum sweat consumption of only 0.5 ml h−1 can cool the skin to a comfortable temperature, preventing harmful excessive sweating. Additionally, the bioinspired metafabric also possesses favorable wearability and color expansibility. Given these first‐rate features, the bioinspired metafabric will pave the way for the development of advanced functional fabrics. [ABSTRACT FROM AUTHOR]

Polyolefin separators, such as polypropylene (PP) and polyethylene (PE) separators, are the commonly used separators for lithium batteries, which have good mechanical properties and chemical/electrochemical stability, but their high‐temperature dimensional stability is poor and Li+ transference number (t Li+) is low. Recently, much attention has been paid to developing separators with new substrates, but so far there is no separator to replace the polyolefin separator for large‐scale application. Therefore, the surface modification of the polyolefin separator to enhance its functionality is a simple and effective method. Among many modified layers, the porous modified layer can store the electrolyte and provide enough space for ion transport. In this work, a hollow mesoporous silica nanosphere (mSiO2) is prepared for the PP separator multifunctional coating to improve the electrochemical performance and high‐temperature safety of the PP separator. The experimental and theoretical results show that the mSiO2 coating can not only improve the electrolyte wettability and high‐temperature dimensional stability of the PP separator, but also promote the Li+ transport, so that the mSiO2/PP separator exhibits high ionic conductivity (2.35 mS cm−1) and high t Li+ (0.63). As a result, Li//LiFePO4 cells using mSiO2/PP separators exhibit excellent cycling performance, rate performance, and high‐temperature safety. [ABSTRACT FROM AUTHOR]

Although molecular tetrahedral Ti-oxo species exhibit unique electronic and photochemical properties due to their discrete energy levels, which are different from those of anatase and rutile, such Ti-oxo species are generally unstable and readily transformed to amorphous/crystalline TiO2 (bulk phases, nanoparticles and clusters) via hydrolysis and condensation. Here, molecular Ti-oxo species were immobilised within mesoporous silica SBA-15 by grafting titanium(IV) oxyacetylacetonate using the surface silanol groups of SBA-15 as a scaffold, followed by chemical etching with dilute hydrochloric acid to form molecular TiO4 species. These Ti species mainly exist as isolated tetrahedrally coordinated structures, as was confirmed by diffuse reflectance UV-vis and Raman spectroscopy. The SBA-15-immobilised molecular TiO4 exhibited higher photocatalytic activity for H2 evolution from an aqueous methanol solution than conventional Ti-incorporated mesoporous silica (Ti-MCM-41) and reference TiO2 (P25). [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles (MSNs) have emerged as promising drug carriers that can facilitate targeted anticancer drug delivery, but efficiency studies relying on active targeting mechanisms remain elusive. This study implements in vitro 3D cocultures, so‐called microtissues, to model a physiologically relevant tumor microenvironment (TME) to examine the impact of surface‐modified MSNs without targeting ligands on the internalization, cargo delivery, and cargo release in tumor cells and cancer‐associated fibroblasts. Among these, acetylated MSNs most effectively localized in tumor cells in a 3D setting containing collagen, while other MSNs did so to a lesser degree, most likely due to remaining trapped in the extracellular matrix of the TME. Confocal imaging of hydrophobic model drug‐loaded MSNs demonstrated effective cargo release predominantly in tumor cells, both in 2D and 3D cocultures. MSN‐mediated delivery of an anticancer drug in the microtissues exhibited a significant reduction in tumor organoid size and enhanced the tumor‐specific cytotoxic effects of a γ‐secretase inhibitor, compared to the highly hydrophobic drug in free form. This inherent targeting potential suggests reduced off‐target effects and increased drug efficacy, showcasing the promise of surface modification of MSNs as a means of direct cell‐specific targeting and delivery for precise and successful targeted drug delivery. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are receiving increasing interest in biomedical applications. However, due to their large surface area, in physiological environments, they tend to interact with plasma proteins, inducing their agglomeration and ultimately resulting in a substantial efficiency decrease in diagnostic and therapeutic applications. To overcome such problems, NPs are typically coated with a layer of hydrophilic and biocompatible polymers, such as PEG chains. However, few examples exist in which this property could be systematically fine-tuned and combined with added properties, such as emission. Herein, we report a novel mussel-inspired catechol-based strategy to obtain biocompatible and multifunctional coatings, using a previously developed polymerization methodology based on the formation of disulfide bridges under mild oxidative conditions. Two families of NPs were selected as the proof of concept: mesoporous silica NPs (MSNPs), due to their stability and known applications, and magnetite NPs (Fe3O4 NPs), due to their small size (<10 nm) and magnetic properties. The PEG coating confers biocompatibility on the NPs and can be further functionalized with bioactive molecules, such as glucose units, through the end carboxylic acid moieties. Once we demonstrated the feasibility of our approach to obtaining PEG-based coatings on different families of NPs, we also obtained multifunctional coatings by incorporating fluorescein functionalities. The resulting coatings not only confer biocompatibility and excellent cell internalization, but also allow for the imaging and tracking of NPs within cells. [ABSTRACT FROM AUTHOR]

SBA-15 and organic ionic liquid were incorporated in a post-grafting technique for generating a bifunctional ionic liquid embedded mesoporous SBA-15. The prepared heterogeneous catalyst was employed for the first time to synthesize N-alkylated indoline-2,3-dione at mild conditions to afford excellent yields in a short reaction time. The synthesized DABCOIL@SBA-15 catalyst was meticulously characterized by various techniques, such as FT-IR, solid-state 13C NMR, solid-state 29Si NMR, small-angle X-ray diffraction (XRD), and N2 adsorption–desorption. Further, the morphological behavior of the catalyst was studied by SEM and TEM. The thermal stability and number of active sites were determined by thermogravimetric analysis (TGA). The Hammett equation was used to analyze the synergetic effect of the catalyst and substituent effects on the N-alkylated products of 5-substituted isatin derivatives, which resulted in a negative slope. This negative slope indicates a positive charge in the transition state. Notably, the DABCOIL@SBA-15 catalyst demonstrated its practicality by being reused for seven cycles with consistently high catalytic activity. [ABSTRACT FROM AUTHOR]

In recent decades, immunotherapy has been considered a promising treatment approach. The modulatable enhancement or attenuation of the body's immune response can effectively suppress tumors. However, challenges persist in clinical applications due to the lack of precision in antigen presentation to immune cells, immune escape mechanisms, and immunotherapy-mediated side effects. As a potential delivery system for drugs and immunomodulators, mesoporous silica has attracted extensive attention recently. Mesoporous silica nanoparticles (MSNs) possess high porosity, a large specific surface area, excellent biocompatibility, and facile surface modifiability, making them suitable as multifunctional carriers in immunotherapy. This article summarizes the latest advancements in the application of MSNs as carriers in cancer immunotherapy, aiming to stimulate further exploration of the immunomodulatory mechanisms and the development of immunotherapeutics based on MSNs. [ABSTRACT FROM AUTHOR]

Mesoporous silica, as a drug carrier, has become the new research focus in the field of nanodrug delivery system in recent years. In this study, Mn-doped mesoporous silicas are synthesized by template and in-situ doping method and physically characterized. The drug-loading performance of silica and its impact on drug release are studied. The Mn-doped mesoporous silicas show dendritic morphology (MDMS) with a loose wrinkle structure on the surface and a large number of pores. MDMS is used as a carrier to solve the problem of low water solubility of paclitaxel. In order to avoid leakage during drug transportation, the surface of Mn-doped mesoporous silica loaded with paclitaxel is coated with N-succinyl chitosan to construct a new type of nanodrug delivery system (MDMS-PTX-NSC). Compared to MDMS, MDMS-PTX-NSC shows an increase in particle size and smooth surface. The dissolution characteristics of manganese ions and swelling behavior of N-succinyl chitosan make MDMS-PTX-NSC delivery system exhibit a good pH-responsive release. And MDMS-PTX-NSC release curve can be well fitted by Ritger-Peppas equation. The cytotoxicity test shows that the MDMS-PTX-NSC has significant biocompatibility and enhanced cytotoxicity, which reveals that the MDMS-PTX-NSC is a promising nanodrug delivery system. By template and in-situ doping method, Mn-doped dendritic mesoporous silica (MDMS) was prepared, which was then loaded with paclitaxel (PTX) and coated using a N-succinyl chitosan (NSC) to develop a new nanodrug delivery system (MDMS-PTX-NSC). Due to the dissolution characteristics of manganese ions and swelling behavior of N-succinyl chitosan, the MDMS-PTX-NSC delivery system exhibited a sufficient pH-responsive release, significant biocompatibility, and enhanced cytotoxicity. [ABSTRACT FROM AUTHOR]

New magnetic yolk-shell mesoporous silica nanoparticles (Fe3O4@V-mSiO2-PNVCL) were prepared by grafting temperature-sensitive amino-terminated poly (N-vinylcaprolactam) (PNVCL-NH2) on the surface of aldehyde-functionalized magnetic mesoporous silica nanoparticles (Fe3O4@V-mSiO2-CHO) through a Schiff base reaction. Various characterizations were used to confirm the structures, and the drug loading and release behaviors were studied. The drug loading was achieved as PNVCL stretched at room temperature and the drug loading content was up to 54.7% due to the large cavities. The encapsulation of drug from leakage in the blood environment was realized as PNVCL collapsed at physiological temperature. The fracture of pH-liable imine bonds in a slightly acidic tumor environment triggered the burst release of cargo. The Fe3O4@V-mSiO2-PNVCL showed super paramagnetic behavior (21.01 emu∙g−1) which could achieve magnetic targeting. The MTT assay confirmed that the nanoparticles exhibited low cytotoxicity. Furthermore, the cellular uptake experiments indicated that DOX-loaded nanoparticles were successfully internalized into cancer cells. Therefore, the composite nanoparticles are ideal choices for drug carriers. [ABSTRACT FROM AUTHOR]

In this study, spherical silica with pore size varied from 30 to 200 Å was synthesized by pseudomorphic transformation at atmospheric pressure. 40–80 Å silica particles with a narrow pore distribution were obtained by using quaternary amine cationic surfactants and different kinds of swelling agents, including polypropylene glycol, 1,3,5‐trimethylbenzene, alkanes, and alkanols. Alkyl imidazolium ionic liquid surfactants were used to synthesize large pore size distribution silica spheres with pore sizes in the range of 110–200 Å. All these silica particles can be synthesized under mild conditions within 12 h, which provides a facile synthesis method for the preparation of a chromatographic matrix with tunable pore size. The method is reproducible and the relative standard deviation of silica sphere pore structure parameters in scaled‐up preparations is less than 6%. The pore size on the fraction of low‐molecular‐weight heparin (LMWH) was investigated in size exclusion chromatography. Matrixes with different pore size distributions have various size exclusion regions. By using UPS‐60‐Diol columns in a twin‐column recirculation separation process, LMWH with >85% heparin with molecular weight within the range of 3000–8000 Da were separated in five‐column volumes. [ABSTRACT FROM AUTHOR]

Plastic pollution is a critical environmental issue due to the widespread use of plastic materials and their long degradation time. Hydrocracking (HDC) offers a promising solution to manage plastic waste by converting it into valuable products, namely chemicals or fuels. This work aims to investigates the effect of catalyst accessibility and acidity on the HDC reaction of high density polyethylene (HDPE). Therefore, a variety of materials with significant differences in both textural and acidic properties were tested as catalysts. These include H-USY and H-ZSM.5 zeolites with various Si/Al molar ratios (H-USY: Si/Al = 2.9, 15, 30 and 40; H-ZSM-5: Si/Al = 11.5, 40, 500) and mesostructured MCM-41 materials modified with Ga and Al, also with different Si/metal ratios (Si/Al = 16 and 30; Si/Ga = 63 and 82). Thermogravimetric analysis under hydrogen atmosphere was used as a preliminary screening tool to evaluate the potential of the various catalysts for this application in terms of energy requirements. In addition, batch autoclave reactor experiments (T = 300 °C, PH2 = 20 bar, t = 60 min) were conducted to obtain further information on conversion, product yields and product distribution for the most promising systems. The results show that the catalytic performance in HDPE hydrocracking is determined by a balance between the acidity of the catalyst and its structural accessibility. Accordingly, for catalyst series where the structural and textural properties do not vary with the Si/Al ratio, there is a clear correlation of the HDPE degradation temperature and of the HDPE conversion with the Si/metal ratio (which relates to the acidic properties). In contrast, for catalyst series where the structural and textural properties vary with the Si/Al ratio, no consistent trend is observed and the catalytic performance is determined by a balance between the acidic and textural properties. The product distribution was also found to be influenced by the physical and chemical properties of the catalyst. Catalysts with strong acidity and smaller pores were observed to favor the formation of lighter hydrocarbons. In addition to the textural and acidic properties of the catalyst, the role of coke formation should not be neglected to ensure a comprehensive analysis of the catalytic performance. [ABSTRACT FROM AUTHOR]

Intravitreal injection of biodegradable implant drug carriers shows promise in reducing the injection frequency for neovascular retinal diseases. However, current intravitreal ocular devices have limitations in adjusting drug release rates for individual patients, thereby affecting treatment effectiveness. Accordingly, we developed mesoporous silica nanoparticles (MSNs) featuring a surface that reverse its charge in response to reactive oxygen species (ROS) for efficient delivery of humanin peptide (HN) to retinal epithelial cells (ARPE-19). The MSN core, designed with a pore size of 2.8 nm, ensures a high HN loading capacity 64.4% (w /w). We fine-tuned the external surface of the MSNs by incorporating 20% Acetyl-L-arginine (Ar) to create a partial positive charge, while 80% conjugated thioketal (TK) methoxy polyethylene glycol (mPEG) act as ROS gatekeeper. Ex vivo experiments using bovine eyes revealed the immobilization of Ar-MSNs-TK-PEG (mean zeta potential: 2 mV) in the negatively charged vitreous. However, oxidative stress reversed the surface charge to −25 mV by mPEG loss, facilitating the diffusion of the nanoparticles impeded with HN. In vitro studies showed that ARPE-19 cells effectively internalize HN-loaded Ar-MSNs-TK, subsequently releasing the peptide, which offered protection against oxidative stress-induced apoptosis, as evidenced by reduced TUNEL and caspase3 activation. The inhibition of retinal neovascularization was further validated in an in vivo oxygen-induced retinopathy (OIR) mouse model. The study discusses the development of a novel drug delivery system utilizing charge reversal mesoporous silica nanoparticles (MSNs) for the treatment of neovascular retinal diseases. [Display omitted] • Mesoporous Silica Nanoparticles' surface charge was delicately adjusted for reversal under ROS-response. • Intravitreal injection of Ar-MSNs-TK-PEG was immobilized in the mouse vitreous; however, under oxidative stress, the surface charge reversed, facilitating nanoparticle diffusion. • HN loaded Ar-MSNs-TK-PEG provides protection against oxidative stress-induced apoptosis, evidenced by reduced TUNEL and caspase3 activation. • Intravitreal injection of HN-loaded Ar-MSNs-TK-PEG inhibit retinal neovascularization in a mice model of oxygen-induced retinopathy without inducing toxicity in retinal tissues. [ABSTRACT FROM AUTHOR]

Numerous nanomedicines have been developed recently that can accumulate selectively in tumours due to the enhanced permeability and retention (EPR) effect. However, the high interstitial fluid pressure (IFP) in solid tumours limits the targeted delivery of nanomedicines. We were previously able to relieve intra-tumoural IFP by low-frequency non-focused ultrasound (LFNFU) through ultrasonic targeted microbubble destruction (UTMD), improving the targeted delivery of FITC-dextran. However, the accumulation of nanoparticles of different sizes and the optimal acoustic pressure were not evaluated. In this study, we synthesised Cy5.5-conjugated mesoporous silica nanoparticles (Cy5.5-MSNs) of different sizes using a one-pot method. The Cy5.5-MSNs exhibited excellent stability and biosafety regardless of size. MCF7 tumour-bearing mice were subjected to UTMD over a range of acoustic pressures (0.5, 0.8, 1.5 and 2.0 MPa), and injected intravenously with Cy5.5-MSNs. Blood perfusion, tumour IFP and intra-tumoural accumulation of Cy5.5-MSNs were analysed. Blood perfusion and IFP initially rose, and then declined, as acoustic pressure intensified. Furthermore, UTMD significantly enhanced the accumulation of differentially sized Cy5.5-MSNs in tumour tissues compared to that of the control group, and the increase was sevenfold higher at an acoustic pressure of 1.5 MPa. Taken together, UTMD enhanced the infiltration and accumulation of Cy5.5-MSNs of different sizes in solid tumours by reducing intra-tumour IFP. The synthesis of Cy5.5-MSN and the effect of UTMD on its infiltration into tumours (produced using Figdraw, ). (A) The synthesis route of Cy5.5-MSN. (B, C) The impact of UTMD on the infiltration of Cy5.5-MSN into tumours. [ABSTRACT FROM AUTHOR]

In this work, KIT‐6@Schiff‐base@Ce nanocatalyst was synthesized by immobilizing the Ce complex on KIT‐6 mesoporous silica framework modified with 3‐iodopropyltrimethoxysilane group. The surface area, total volume, and average diameter of pores, physical properties, functional groups, organic content, and element combination of the obtained nanocatalyst were identified using different techniques including BET, FT‐IR, XRD, WDX, SEM, and EDX. The KIT‐6@Schiff‐base@Ce was investigated as a novel stable and reusable catalyst with excellent performance for the selective synthesizing of sulfoxide and tetrahydrobenzo[b]pyrans. The designed catalyst successfully oxidized a large number of sulfides using hydrogen peroxide under solvent‐free conditions or in ethanol as a safe, green, and available solvent with good efficiency within short reaction times. Also, KIT‐6@Schiff‐base@Ce catalyzed a number of tetrahydrobenzo[b]pyrans using multicomponent condensation of dimedone, aldehydes, and malononitrile in water/ethanol (1:1) as ideal, safe, green and available solvent. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles (MSNs) are physically and chemically stable inorganic nanomaterials that have been attracting much attention as carriers for drug delivery systems in the field of nanomedicine. In the present study, we investigated the potential of MSN vaccines that incorporate antigen peptides for use in cancer immunotherapy. In vitro experiments demonstrated that fluorescently labeled MSNs accumulated in a line of mouse dendritic cells (DC2.4 cells), where the particles localized to the cytosol. These observations could suggest that MSNs have potential for use in delivering the loaded molecules into antigen-presenting cells, thereby stimulating the host acquired immune system. In vivo experiments demonstrated prolonged survival in mice implanted with ovalbumin (OVA)-expressing lymphoma cells (E.G7-OVA cells) following subcutaneous inoculation with MSNs incorporating OVA antigen peptides. Furthermore, OVA-specific immunoglobulin G antibodies and cytotoxic T lymphocytes were detected in the serum and the spleen cells, respectively, of mice inoculated with an MSN-OVA vaccine, indicating the induction of antigen-specific responses in both the humoral and cellular immune systems. These results suggested that the MSN therapies incorporating antigen peptides may serve as novel vaccines for cancer immunotherapy. [ABSTRACT FROM AUTHOR]

[Display omitted] As an emerging fluorophore, aggregation-induced emission luminogens (AIEgens) have received widespread attention in recent years, but the inherent drawbacks of AIEgens, such as the poor water-solubility and insufficient fluorescence stability in complex environments, restrict their performance in practical applications. Herein, we report a universal strategy based on hydrophobic dendritic mesoporous silica (HMSN) that can integrate different AIE molecules to construct multi-color fluorescent AIE materials. Specifically, HMSN with central radial pores was used as a powerful carrier for direct loading AIE molecules and restricting their intramolecular motions. Due to the pore-domain restriction effect and hydrophobic interaction, the obtained silica-based AIE materials have bright fluorescence with a maximum quantum yield of 68.38%, high colloidal/fluorescence stability, and excellent biosafety. Further, these silica-based AIE materials can be conjugated with functional antibodies to obtain probes with different targetability. After integration with immunomagnetic beads, the prepared detection probes achieved the quantitative detection of cardiac troponin I with the limit of detection (LOD) of 0.508 ng/mL. Overall, the targeting probes stemming from silica-based AIE materials can not only achieve cell-specific imaging, but quantify the number of Jurkat cells (LOD = 270 cells/mL) to further determine the specific etiology of the disease. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mesoporous‐nanostructured silica‐Prussian blue composite is a highly potential material for silver ions removal and recovery from wastewater. Intense interest has been shown in the use of Prussian blue (PB), one of the important coordinated materials and its analogues in removal of toxic and valuable ions. METHODS: The micro‐emulsion template method enables the synthesis of Prussian blue (PB) within silica pores, yielding a nanostructured mesoporous silica‐PB composite. This rapid synthesis technique allows for the direct fabrication of the composite from mixed precursor solutions within minutes. The resulting material is effective for selectively extracting silver ions from wastewater at a specific pH level. RESULTS AND DISCUSSION: In summary, the synthesized SiO2‐Prussian blue composite was extensively analyzed using various techniques including XPS, HR‐TEM, SEM, STEM‐EDX elemental maps, TGA/TDA, and N2 adsorption/desorption measurements. The composite exhibited a BET surface area of 203 m2 g−1 and a total pore volume of approximately 0.283 cm3 g−1with mesopores centered around 20 nm. This mesoporous SiO2‐Prussian blue demonstrated significant effectiveness in removing silver ions, with a maximum adsorption capacity of 107.5 mg g−1. The Langmuir and Sips isotherms showed the best fit among various adsorption isotherm types, with R2 values exceeding 0.984. Additionally, kinetic analyses revealed that the pseudo‐second‐order model accurately described the adsorption of silver ions onto the synthesized adsorbent. The nano‐particles exhibit remarkable long‐term stability, maintaining good reproducibility even after five regeneration cycles. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Chemotherapeutic drug delivery systems are commonly limited by their short half-lives, poor bioavailability, and unsuccessful targetability. Herein, pH-responsive hybrid NPs consist of benzimidazole-coated mesoporous silica nanoparticles (BZ-MSN) loaded with naturally occurring flavonoid quercetin (QUE-BZ-MSN). The NPs were further capped with beta-cyclodextrin (BCD) to obtain our desired BCD-QUE-BZMSN, with a zeta potential around 7.05 ± 2.37 mV and diameter about 115.2 ± 19.02 nm. The abundance of BZ onto the nanoparticles facilitates targeted quercetin chemotherapy against model lung and liver cancer cell lines. FTIR, EDX, and NMR analyses revealed evidence of possible surface functionalizations. Powder XRD analysis showed that our designed BCD-QUE-BZMSN formulation is amorphous in nature. The UV and SEM showed that our designed BCD-QUE-BZMSN has high drug entrapment efficiency and a nearly spherical morphology. In vitro, drug release assessments show controlled pH-dependent release profiles that could enhance the targeted chemotherapeutic response against mildly acidic regions in cancer cell lines. The obtained BCD-QUE-BZMSN nanovalve achieved significantly higher cytotoxic efficacy as compared to QUE alone, which was evaluated by in vitro cellular uptake against liver and lung cancer cell lines, and the cellular morphological ablation was further confirmed via inverted microscopy. The outcomes of the study imply that our designed BCD-QUE-BZMSN nanovalve is a potential carrier for cancer chemotherapeutics. [ABSTRACT FROM AUTHOR]