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It has been shown that associates of cationic glycerolipid (CGL), rac-N-{4-[(2-ethoxy-3-octadecyloxyprop-1-yl)oxycarbonyl]butyl}-N'-methylimidazolium iodide, which has a pronounced antitumor effect, can be used for the solubilization of two hydrophobic biologically active compounds (curcumin and capsaicin) and as templates in the sol–gel synthesis of silica mesoporous container particles (MCPs). The thermodynamic characteristics of solubilization are determined, and it is shown that this process contributes to a significant increase in the solubility of both hydrophobic drugs in water. The hydrolytic condensation of tetraethoxysilane in the presence of CGL associates containing curcumin or capsaicin leads to the formation of MCPs characterized by a narrow size distribution and a high content of encapsulated drugs. This combination of the stages of the synthesis and loading of MCPs is of undoubted interest in relation to the nanoencapsulation of cationic glycerolipids (including in combination with other drugs). [ABSTRACT FROM AUTHOR]

Pulmonary delivery and formulation of biologics are among the more complex and growing scientific topics in drug delivery. We herein developed a dry powder formulation using disordered mesoporous silica particles (MSP) as the sole excipient and lysozyme, the most abundant antimicrobial proteins in the airways, as model protein. The MSP had the optimal size for lung deposition (2.43 ± 0.13 µm). A maximum lysozyme loading capacity (0.35 mg/mg) was achieved in 150 mM PBS, which was seven times greater than that in water. After washing and freeze-drying, we obtained a dry powder consisting of spherical, non-aggregated particles, free from residual buffer, or unabsorbed lysozyme. The presence of lysozyme was confirmed by TGA and FT-IR, while N2 adsorption/desorption and SAXS analysis indicate that the protein is confined within the internal mesoporous structure. The dry powder exhibited excellent aerodynamic performance (fine particle fraction <5 µm of 70.32%). Lysozyme was released in simulated lung fluid in a sustained kinetics and maintaining high enzymatic activity (71–91%), whereas LYS-MSP were shown to degrade into aggregated nanoparticulate microstructures, reaching almost complete dissolution (93%) within 24 h. MSPs were nontoxic to in vitro lung epithelium. The study demonstrates disordered MSP as viable carriers to successfully deliver protein to the lungs, with high deposition and retained activity. [ABSTRACT FROM AUTHOR]

This work presents a novel hydrothermally aided sol-gel method for preparation of mesoporous silica nanoparticles (MSNs) with a narrow particle size distribution and varied pore sizes. The method was carried out in alkaline media in presence of polyethylene glycol (PEG) and cetyltrimethylammonium chloride (CTAC) as dual templates and permitted the synthesis of spherical mesoporous silica with a high surface area (1011.42 m2/g). The MSN materials were characterized by FTIR, Thermogravimetric (TG), Nitrogen adsorption and desorption and Field emission scanning electron microscopic analysis (FESEM). The materials feasibility as solid phase adsorbent has been demonstrated using cationic dyes; Rhodamine B (RB) and methylene blue (MB) as models. Due to the large surface area and variable pore width, the adsorption behaviors toward cationic dyes showed outstanding removal efficiency and a rapid sorption rate. The adsorption isotherms of RB and MB were well-fitted to the Langmuir and Freundlich models, while the kinetic behaviours adhered closely to the pseudo-second-order pattern. The maximum adsorption capacities were determined to be 256 mg/g for MB and 110.3 mg/g for RB. The findings suggest that MSNs hold significant potential as solid-phase nanosorbents for the extraction and purification of dye pollutants, particularly in the analysis and treatment of effluents containing cationic dyes. [ABSTRACT FROM AUTHOR]

Over 70% of pharmaceutical compounds face the challenge of poor water solubility, which impacts on their bioavailability. This study focuses on the use of Santa Barbara Amorphous‐15 (SBA‐15) mesoporous silica material as carrier, which is synthesized and characterized to address this limitation. Albendazole (ABZ), an antiparasitic agent with low water solubility, serves as model drug. A Box‐Behnken design (BBD) is used to investigate the impact of immersion method loading factors (temperature: 25–50 °C, time: 24–72 h, and SBA‐15 amount: 83.2–252.0 mg) on drug loading percentage (DL%) and dissolution efficiency (DE%). The ABZ loading is confirmed by elemental analysis and Fourier transform infrared spectroscopy. Stability tests are performed, comparing drug dissolution profiles and X‐ray diffraction patterns immediately after loading and after 12 months of storage at 25 °C and 60% relative humidity (RH%). DL% varies between 18% and 36% (w/w), showing that the amount of SBA‐15 is the most significant factor on DL%. The lowest SBA‐15 amount yielded the highest DL%. Regarding DE%, all the design samples exhibit higher values than pure ABZ, with the amount of SBA‐15 being the primary influencing factor. Several samples from the BBD show high DE% (>70%) corresponding to high DL% values. After 12 months, most samples maintain similar dissolution profiles, demonstrating the good stability of the drug in the carrier over time. This study provides valuable insights into optimizing the loading process to enhance ABZ solubility and long‐term stability using mesoporous SBA‐15. [ABSTRACT FROM AUTHOR]

Mesoporous silica particles (MSPs) have been investigated as potential carriers to increase the apparent solubility and dissolution rate of poorly water-soluble drugs by physically stabilising the amorphous nature of the loaded drug. In preparing such systems, it is recognized that the loading method has a critical impact on the physical state and performance of the drug. To date, there has been very limited investigation into the use of electrospraying for loading drugs into mesoporous silica. In this study, we further explore the use of this approach, in particular as a means of producing amorphous and high drug-loaded MSPs; the study includes an investigation of the effect of drug loading and MSP concentration on the formulation performance and process. A comparison with rotary evaporation, a more widely utilised loading technique, was conducted to assess the relative effectiveness of electrospraying. The physical state of the drug in the formulations was assessed using powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC). The drug release profiles were determined by a comparative in vitro drug release test. Electrospraying successfully produced formulations containing amorphous drug even at a high drug loading. In contrast, while itraconazole was present in amorphous form at the lower drug-loaded formulations produced by rotary evaporation, the drug was in the crystalline state at the higher loadings. The percentage of drug released was enhanced up to ten times compared to that of pure itraconazole for all the formulations apart from the highest loaded (crystalline) formulation prepared by rotary evaporation. Supersaturation for at least six hours was maintained by the formulations loaded with up to 30 mg/mL itraconazole produced by electrospraying. Overall, the results of this study demonstrate that electrospraying is capable of producing amorphous drug-loaded MSPs at high loadings, with associated favourable release characteristics. A comparison with the standard rotary evaporation approach indicates that electrospraying may be more effective for the production of higher loadings of amorphous material. [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]

Pulmonary delivery and formulation of biologics are among the more complex and growing scientific topics in drug delivery. We herein developed a dry powder formulation using disordered mesoporous silica particles (MSP) as the sole excipient and lysozyme, the most abundant antimicrobial proteins in the airways, as model protein. The MSP had the optimal size for lung deposition (2.43 ± 0.13 µm). A maximum lysozyme loading capacity (0.35 mg/mg) was achieved in 150 mM PBS, which was seven times greater than that in water. After washing and freeze-drying, we obtained a dry powder consisting of spherical, non-aggregated particles, free from residual buffer, or unabsorbed lysozyme. The presence of lysozyme was confirmed by TGA and FT-IR, while N2 adsorption/desorption and SAXS analysis indicate that the protein is confined within the internal mesoporous structure. The dry powder exhibited excellent aerodynamic performance (fine particle fraction

The cancer vaccine is one of the potent cancer immunotherapies based on provoking antigen‐specific adaptive immune responses in patients. Activating host antigen‐presenting cells by delivering antigens and adjuvants is one of the most important requirements to enhance cancer vaccine efficacy. This study proposes an effective cancer vaccine platform based on injectable mesocellular foam (MCF) silica microparticles with a dual role capable of in situ recruitment of host dendritic cells (DCs) and intracellular delivery of antigens to the recruited DCs. Subcutaneously administrated MCF microparticles loaded with chemoattractant to DCs (GM‐CSF), antigenic protein (OVA), and TLR9 agonist (CpG‐ODN) lead to robust DC maturation and high antigen‐specific T cell responses. The cell recruitment, DC activation, and T cell responses of MCF‐based cancer vaccine are significantly higher than injectable mesoporous silica scaffold, of which role is mostly limited to the cell recruiting scaffold. These features of MCF lead to effective inhibition of tumor growth in prophylactic vaccine setting and lung metastatic cancer model, representing MCF enabling cell‐recruiting scaffold formation and intracellular delivery of antigen can be a promising material platform for an enhanced cancer vaccine. [ABSTRACT FROM AUTHOR]

This work presents a novel hydrothermally aided sol-gel method for preparation of mesoporous silica nanoparticles (MSNs) with a narrow particle size distribution and varied pore sizes. The method was carried out in alkaline media in presence of polyethylene glycol (PEG) and cetyltrimethylammonium chloride (CTAC) as dual templates and permitted the synthesis of spherical mesoporous silica with a high surface area (1011.42 m2/g). The MSN materials were characterized by FTIR, Thermogravimetric (TG), Nitrogen adsorption and desorption and Field emission scanning electron microscopic analysis (FESEM). The materials feasibility as solid phase adsorbent has been demonstrated using cationic dyes; Rhodamine B (RB) and methylene blue (MB) as models. Due to the large surface area and variable pore width, the adsorption behaviors toward cationic dyes showed outstanding removal efficiency and a rapid sorption rate. The adsorption isotherms of RB and MB were well-fitted to the Langmuir and Freundlich models, while the kinetic behaviours adhered closely to the pseudo-second-order pattern. The maximum adsorption capacities were determined to be 256 mg/g for MB and 110.3 mg/g for RB. The findings suggest that MSNs hold significant potential as solid-phase nanosorbents for the extraction and purification of dye pollutants, particularly in the analysis and treatment of effluents containing cationic dyes.

The utilization of novel materials in the biofuel production domain has been regarded as a significant advancement in catalyst development. Incorporating lipases in biodiesel manufacturing is often viewed as a cost-restrictive phase since the expenses associated with recovering these catalysts can render market expectations unfeasible. Within this investigation, mesoporous silica (MPS) particles were assessed as a supporting medium for immobilizing commercial lipase, subsequent to their utilization in ethyl ester synthesis. Initially, the production of mesoporous silica was achieved through the co-precipitation technique at a consistent pH and was subsequently chosen as an immobilization support for the enzyme. The characterization of the biocatalyst support materials produced was performed using various analytical methods including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and BET analysis. The Novozym 435 lipase was then immobilized within the matrices, followed by the transesterification process of algal oil derived from Nannochloropsis. The resulting biodiesel samples demonstrated compliance with commercial standards, exhibiting an ester conversion rate exceeding 94.8 %. Additionally, properties such as density (0.93 g cm−3) and viscosity (5.01 mm2 s−1) satisfied the specifications mandated by ASTM for biofuel application. Experimental planning techniques showed that increasing lipase loading and using temperatures between 38 and 48 °C resulted in higher conversion rates of ethyl esters. This confirms the effectiveness of the enzymatic catalyst in generating primary fatty acid esters, even with residual lipid feedstocks.

Mesoporous silica particles (MSPs) have been investigated as potential carriers to increase the apparent solubility and dissolution rate of poorly water-soluble drugs by physically stabilising the amorphous nature of the loaded drug. In preparing such systems, it is recognized that the loading method has a critical impact on the physical state and performance of the drug. To date, there has been very limited investigation into the use of electrospraying for loading drugs into mesoporous silica. In this study, we further explore the use of this approach, in particular as a means of producing amorphous and high drug-loaded MSPs; the study includes an investigation of the effect of drug loading and MSP concentration on the formulation performance and process. A comparison with rotary evaporation, a more widely utilised loading technique, was conducted to assess the relative effectiveness of electrospraying. The physical state of the drug in the formulations was assessed using powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC). The drug release profiles were determined by a comparative in vitro drug release test. Electrospraying successfully produced formulations containing amorphous drug even at a high drug loading. In contrast, while itraconazole was present in amorphous form at the lower drug-loaded formulations produced by rotary evaporation, the drug was in the crystalline state at the higher loadings. The percentage of drug released was enhanced up to ten times compared to that of pure itraconazole for all the formulations apart from the highest loaded (crystalline) formulation prepared by rotary evaporation. Supersaturation for at least six hours was maintained by the formulations loaded with up to 30 mg/mL itraconazole produced by electrospraying. Overall, the results of this study demonstrate that electrospraying is capable of producing amorphous drug-loaded MSPs at high loadings, with associated favourable release characteristics. A comparison with the standard rotary evaporation approach indicates that electrospraying may be more effective for the production of higher loadings of amorphous material.

Folic acid (FA), a water-soluble vitamin (B9), is crucial for metabolic activities and regulatory processes of cells. Mammalian cells cannot synthesize any form of folate, thereby necessitating their exogenous supply. Further, FA is degraded by light, heat, oxidation, and external conditions. Therefore, the need for micro- and nano-encapsulation techniques for FA arises. The present work deals primarily with various encapsulation techniques for FA, including coacervation, electrospraying, electrospinning, nanoemulsions, biopolymer nanoparticles, nanohydrogels, and mesoporous silica particles from research studies, elaborately described with relevant justifications and other novel techniques. An overview of FA is provided and its structural aspects and factors affecting its degradation are discussed. The review also comprehensively discusses the controlled release mechanisms and factors affecting FA release from encapsulation systems. Pharmacokinetic studies conducted to assess the bioavailability of FA post oral administration are mentioned. The novel techniques with the highest encapsulation efficiency of FA were proliposomes, electrospinning, and double emulsification. Additionally, the highest FA serum concentration obtained in oral bioavailability studies was found in a novel desolvation process cum ultrafiltration encapsulation method using zein as the encapsulant. The positive impact of specific techniques and the future scope along with suggestions for FA encapsulation systems are examined. [ABSTRACT FROM AUTHOR]

Due to their structural, morphological, and behavioral characteristics (e.g., large volume and adjustable pore size, wide functionalization possibilities, excellent biocompatibility, stability, and controlled biodegradation, the ability to protect cargoes against premature release and unwanted degradation), mesoporous silica particles (MSPs) are emerging as a promising diagnostic and delivery platform with a key role in the development of next-generation theranostics, nanovaccines, and formulations. In this study, MSPs with customized characteristics in-lab prepared were fully characterized and used as carriers for doxorubicin (DOX). The drug loading capacity and the release profile were evaluated in media with different pH values, mimicking the body conditions. The release data were fitted to Higuchi, Korsmeyer–Peppas, and Peppas–Sahlin kinetic models to evaluate the release constant and the mechanism. The in vitro behavior of functionalized silica particles showed an enhanced cytotoxicity on human breast cancer (MCF-7) cells. Bio- and mucoadhesion on different substrates (synthetic cellulose membrane and porcine tissue mucosa)) and antimicrobial activity were successfully assessed, proving the ability of the OH- or the organically modified MSPs to act as antimicrobial and mucoadhesive platforms for drug delivery systems with synergistic effects. [ABSTRACT FROM AUTHOR]

Alendronate (ALN) is the most commonly prescribed oral nitrogen-containing bisphosphonate for osteoporosis therapy. However, its administration is associated with serious side effects. Therefore, the drug delivery systems (DDS) enabling local administration and localized action of that drug are still of great importance. Herein, a novel multifunctional DDS system based on the hydroxyapatite-decorated mesoporous silica particles (MSP-NH2-HAp-ALN) embedded into collagen/chitosan/chondroitin sulfate hydrogel for simultaneous osteoporosis treatment and bone regeneration is proposed. In such a system, the hydrogel serves as a carrier for the controlled delivery of ALN at the site of implantation, thus limiting potential adverse effects. The involvement of MSP-NH2-HAp-ALN in the crosslinking process was established, as well as the ability of hybrids to be used as injectable systems. We have shown that the attachment of MSP-NH2-HAp-ALN to the polymeric matrix provides a prolonged ALN release (up to 20 days) and minimizes the initial burst effect. It was revealed that obtained composites are effective osteoconductive materials capable of supporting the osteoblast-like cell (MG-63) functions and inhibiting osteoclast-like cell (J7741.A) proliferation in vitro. The purposely selected biomimetic composition of these materials (biopolymer hydrogel enriched with the mineral phase) allows their biointegration (in vitro study in the simulated body fluid) and delivers the desired physicochemical features (mechanical, wettability, swellability). Furthermore, the antibacterial activity of the composites in in vitro experiments was also demonstrated. [ABSTRACT FROM AUTHOR]

• NQ@MSP-NH 2 induces transient contractions in isolated trachea ring ex vivo model. • NQ@MSP-NH 2 , NQ, and MSP-NH 2 could exert different mechanisms (e.g. NO production). • NQ@MSP-NH 2 may induce hyper-reactivity in airway structures. Biosafety of mesoporous silica particles (MSP) is still controversial since various parameters such as chemical composition, morphology, and entrance route may exert various mechanisms in cells and organs. This report exhibits the first findings of the biological actions induced by MSP loaded with 1,4-naphthoquinone evaluated in a respiratory ex vivo model of isolated trachea ring, suggesting that this complex in cumulative concentrations induced transient contractions in that airway conduit acetylcholine-like profile associated to nitric oxide (NO) production. [ABSTRACT FROM AUTHOR]

Mesoporous silica particles (MSP) have received increasing interest for various applications because of their unique features such as controlled pore size, low density, high chemical and thermal stability, and high surface area. In this study, MSP was applied as an additive in water-based drilling fluids (WBMs). The effect of MSP on the rheological, thermal, filtration, and structural properties of WBMs was investigated. The results were compared with those of analogous fluids containing conventional nonporous silica particles (SSP). Rheological assays showed shear-thinning and viscoelastic behavior, which were more noticeable for fluids including MSP. It was observed that low concentrations of MSP (0.25 %wt) can achieve the same rheological properties as the fluids with higher SSP content (up to 0.5 %wt). The rheological properties of SSP-containing fluids were not significantly affected by the presence of NaCl or aging tests. The theoretical Herschel–Bulkley model represents the rheological behavior of WBMs. The MSP-based WBMs exhibited better filtration properties before aging. The microstructures of the WBMs were analyzed using Scanning Electron Microscopy (SEM). A homogeneous distribution of SSP in the WBMs was observed, while particle agglomeration was observed in WBMs containing MSP. In addition, surface interactions were studied to elucidate the interactions between particles and fluid constituents. The surface interaction, assessed through ζ -potential and FTIR analysis, revealed that the binding affinities of BT, PAC, and XGD with MSP were augmented compared to their individual values. Based on the experimental results, MSP constitutes a promising alternative as an additive for the design of WBMs. [Display omitted] • The effect of silica particles type on water-based drilling fluids (WBMs) performance was investigated. • Lower concentrations of MSP were required to achieve the same rheological properties of the fluids containing SSP. • The physicochemical properties of SSP and MSP had a different effect on the performance of WBMs. • The surface interactions mainly governed the rheological properties of WBMs. [ABSTRACT FROM AUTHOR]

• SBA-15 was functionalized with APTES and L-Lysine (LYS) for CO 2 adsorption. • Repeated APTES and/or LYS treatments do not increase the CO 2 uptake. • Pretreatment before CO 2 adsorption tests plays a key role. • Possible chemical reactions are proposed that may describe the experimental results. • Deamination and other secondary reactions may occur due to the presence of water. In this study, amine-based CO 2 sorbents were synthesized after functionalizing SBA-15 mesoporous materials. Mesoporous SBA-15 was characterized and functionalized by APTES as an alkanolamine, L-lysine as an amino acid and a combination of both. CO 2 adsorption tests were performed at 1.6 and 2 bar to estimate the carbon dioxide (CO 2) uptake on the sorbents. As expected, CO 2 adsorption capacity (mmol/g) increases with pressure. Based on the elemental analysis of the sorbents and the results of Fourier transform infrared spectroscopy (FTIR), a proposal was made of the possible chemical reactions that may occur in order to describe the experimental results. It is important to mention that the pretreatment prior to the CO 2 adsorption tests plays a key role for the application of amine-functionalized mesoporous silica. The presence of water conditions the formation of carbonic acid and carbonate adsorbed on the surface and, consequently, the CO 2 adsorption capacity of the sorbent. APTES and l -lysine loaded onto mesoporous SBA-15 exhibited the highest CO 2 adsorption capacity (4.53 mmol/g) at 2 bar and room temperature. After reloading the sorbents with APTES and Lysine, no improvements in the CO 2 absorption capacity were observed. [ABSTRACT FROM AUTHOR]

Essential oils and their active components have been extensively reported in the literature for their efficient antimicrobial, antioxidant and antifungal properties. However, the sensitivity of these volatile compounds towards heat, oxygen and light limits their usage in real food packaging applications. The encapsulation of these compounds into inorganic nanocarriers, such as nanoclays, has been shown to prolong the release and protect the compounds from harsh processing conditions. Nevertheless, these systems have limited shelf stability, and the release is of limited control. Thus, this study presents a mesoporous silica nanocarrier with a high surface area and well-ordered protective pore structure for loading large amounts of natural active compounds (up to 500 mg/g). The presented loaded nanocarriers are shelf-stable with a very slow initial release which levels out at 50% retention of the encapsulated compounds after 2 months. By the addition of simulated drip-loss from chicken, the release of the compounds is activated and gives an antimicrobial effect, which is demonstrated on the foodborne spoilage bacteria Brochothrixthermosphacta and the potentially pathogenic bacteria Escherichia coli. When the release of the active compounds is activated, a ≥4-log reduction in the growth of B. thermosphacta and a 2-log reduction of E. coli is obtained, after only one hour of incubation. During the same one-hour incubation period the dry nanocarriers gave a negligible inhibitory effect. By using the proposed nanocarrier system, which is activated by the food product itself, increased availability of the natural antimicrobial compounds is expected, with a subsequent controlled antimicrobial effect. [ABSTRACT FROM AUTHOR]

Aim: Mesoporous silica particles (MSPs) are broadly used drug delivery carriers. In this study, the authors analyzed the responses to MSPs of astrocytes and microglia, the two main cellular players in neuroinflammation. Materials & methods: Primary murine cortical mixed glial cultures were treated with rhodamine B-labeled MSPs. Results: MSPs are avidly internalized by microglial cells and remain inside the cells for at least 14 days. Despite this, MSPs do not affect glial cell viability or morphology, basal metabolic activity or oxidative stress. MSPs also do not affect mRNA levels of key proinflammatory genes; however, in combination with lipopolysaccharide, they significantly increase extracellular IL-1β levels. Conclusion: These results suggest that MSPs could be novel tools for specific drug delivery to microglial cells. Mesoporous silica particles (MSPs) are broadly used drug delivery carriers. In this study, the authors analyzed the responses of two types of brain cells, astrocytes and microglia, to MSPs. Mouse astrocytes and microglia were kept alive in cultures and were treated with MSPs that were labeled with a red fluorescent agent to facilitate visualization under the microscope. MSPs are avidly internalized by microglial cells and remain inside the cells for at least 14 days. Despite this, MSPs do not affect glial cell viability or morphology, basal metabolic activity or oxidative stress. When given alone, MSPs do not affect mRNA levels of key proinflammatory genes. However, MSPs given in combination with lipopolysaccharide, a strong proinflammatory agent, significantly increase extracellular levels of IL-1β, one of the proinflammatory mediators studied. These results suggest that MSPs could be novel tools for specific drug delivery to microglial cells. [ABSTRACT FROM AUTHOR]

Brain endothelial cells mediate the function and integrity of the blood brain barrier (BBB) by restricting its permeability and exposure to potential toxins. However, these cells are highly susceptible to cellular damage caused by oxidative stress and inflammation. Consequent disruption to the integrity of the BBB can lead to the pathogenesis of neurodegenerative diseases. Drug compounds with antioxidant and/or anti-inflammatory properties therefore have the potential to preserve the structure and function of the BBB. In this work, we demonstrate the enhanced antioxidative effects of the compound probucol when loaded within mesoporous silica particles (MSP) in vitro and in vivo zebrafish models. The dissolution kinetics were significantly enhanced when released from MSPs. An increased reduction in lipopolysaccharide (LPS)-induced reactive oxygen species (ROS), cyclooxygenase (COX) enzyme activity and prostaglandin E2 production was measured in human brain endothelial cells treated with probucol-loaded MSPs. Furthermore, the LPS-induced permeability across an endothelial cell monolayer by paracellular and transcytotic mechanisms was also reduced at lower concentrations compared to the antioxidant ascorbic acid. Zebrafish pre-treated with probucol-loaded MSPs reduced hydrogen peroxide-induced ROS to control levels after 24-h incubation, at significantly lower concentrations than ascorbic acid. We provide compelling evidence that the encapsulation of antioxidant and anti-inflammatory compounds within MSPs can enhance their release, enhance their antioxidant effects properties, and open new avenues for the accelerated suppression of neuroinflammation. [ABSTRACT FROM AUTHOR]

Aim: To investigate the effect of oral consumption of engineered mesoporous silica particles, SiPore15®, on long-term blood glucose levels and other metabolic parameters in individuals with prediabetes and newly diagnosed Type 2 diabetes. Method: An open-label, single-arm, multicenter trial was conducted in which SiPore15 was consumed three times daily for 12 weeks. Hemoglobin A1c (HbA1c, primary end point) and an array of metabolic parameters were measured at baseline and throughout the trial. Result: SiPore15 treatment significantly reduced HbA1c by a clinically meaningful degree and improved several disease-associated parameters with minimal side effects. Conclusion: The results from this study demonstrate the potential use of SiPore15 as a treatment for prediabetes that may also delay or prevent the onset of Type 2 diabetes. Prediabetes is a health condition in which blood sugar levels are higher than normal but below diabetes diagnosis level. Without intervention, prediabetic adults and children are most likely to progress to Type 2 diabetes. To try and prevent this progression, the authors of this article are proposing an innovative solution with an engineered material called SiPore15®. SiPore15 is classified as a medical device, and is made up entirely of porous silica particles. It has been proven to be safe to take orally. The effects of SiPore15 were investigated in people with prediabetes and newly diagnosed Type 2 diabetes. SiPore15 was taken three times a day for 12 weeks. It significantly reduced long-term blood glucose levels and improved other factors related to the disease with minimal side effects. The results from this study show that SiPore15 has the potential to be used as a treatment for prediabetes. This may help to delay or prevent the onset of Type 2 diabetes. Clinical Trial Registration: NCT03823027 (ClinicalTrials.gov) #Prediabetes is a silent threat. Read about #SiPore15®, a carefully engineered silica powder, and its potential to control blood sugar levels in individuals with prediabetes. [ABSTRACT FROM AUTHOR]

Background: Curcumin likely has wound-healing properties, but its poor pharmacokinetic attributes inhibit its potential. To overcome these limitations, a novel nanoformulation was previously developed, wherein curcumin was loaded into mesoporous silica particles. Objectives: The objective of the study is to assess the efficiency of this nanocurcumin formulation as a wound-healing agent in an animal model. Materials and Methods: Curcumin was loaded onto mesoporous silica particles. Eighteen healthy, test-naive male Wistar rats were randomly separated into two groups of 9: Group 1 (control) rats were treated topically with a standard drug (sulfadiazine) and Group 2 with 1% curcumin formulation. A circular excision wound was made, and topical application was performed twice a day. The excision diameters were measured on days 3, 6, 9, 12, 15, 18 and 21 of treatment. Three rats from each group were sacrificed on days 7, 14 and 21, and a cross-section from skin specimen in the excision injury was obtained for histological assessment of inflammation, angiogenesis, fibroblast proliferation, presence of collagen and reepithelization. Results: Wound contraction percentage in rats treated with curcumin nanoformulation was nonsignificantly higher than that in the control group (P > 0.05). In both groups, inflammatory reactions considerably reduced by day 21 of treatment, the angiogenesis process was almost complete by day 7, fibroblast proliferation noticeably rose by day 14, and a high degree of wound reepithelization was achieved by day 21, with no significant differences between the groups. Interestingly, by day 21, the level of collagen significantly increased in curcumin nanoformulation-treated rats compared with those treated with sulfadiazine. Conclusions: Curcumin nanoformulation likely enhanced wound repair by inhibiting the inflammatory response, stimulating angiogenesis, inducing fibroblast proliferation as well as enhancing reepithelization and synthesis of collagen. Therefore, the curcumin nanoformulation used in this study may have potential as a wound-healing ethnomedicine.

• The phase change heat transfer of nano-enhanced PCMs is addressed. • Mesoporous silica particles are adopted to enhance the thermal conductivity of PCM. • The non-Newtonian behavior of PCM is taken into account using a power-law model. • The results show using the nanoparticles suppresses the convective heat transfer. • Using 5% mass fraction of nanoparticles reduces the heat transfer by 50%. In the present study, the melting phase-change heat transfer of nano-enhanced phase-change octadecane by using mesoporous silica particles is investigated in an inclined cavity, theoretically. The presence of mesoporous silica particles induces non-Newtonian effects in the molten octadecane. A phase-change interface-tracking approach, deformed mesh technique, is employed to track the phase-change interface and heat transfer in the cavity. The Arbitrary Lagrangian-Eulerian (ALE) moving mesh technique along with the finite element method is adopted to solve the governing equations for conservation of mass, momentum, and energy during the phase-change process. A re-meshing technique and an automatic time step control approach are employed to control the quality of the deformed mesh and the computed numerical solution. The effect of various mass fractions of nanoparticles and various inclination angles of the enclosure on the heat transfer and phase-change behavior of nano-enhanced octadecane are addressed. The outcome reveals that using the mesoporous silica particles diminish the heat transfer in the enclosure. Although the presence of nanoparticles improved the conductive heat transfer, a reduction in the phase-change heat transfer performance of the enclosure can be observed, which is due to the increase of the viscosity (consistency parameter) of the liquid and suppression of natural convective flows. Moreover, the presence of nanoparticles reduces the latent heat capacity of octadecane as they do not contribute to the phase-change energy storage. Dispersing 5% mass fraction of nanoparticles in octadecane can reduce the heat transfer up to 50% and increase the consistency parameter by three folds. The angle of inclination of the cavity also plays an important role in the heat transfer characteristics. Tilting the cavity by -75° leads to an 80% reduction in the heat transfer. [ABSTRACT FROM AUTHOR]

BACKGROUND: It is well known that plant essential oils have good antimicrobial activity. However, their strong volatility and intense odor limit their application. Mesoporous silica (MCM‐41), a non‐toxic mesoporous material with excellent loading capability, is a promising delivery system for different types of food ingredients in the food industry. RESULTS: In this study, we first performed component analysis of pepper fragrant essential oil (PFEO) by gas chromatography – mass spectrometry (GC–MS), then the MCM‐41 host was prepared, and the essential oil functionalized nanoparticles (EONs) were formed by embedding PFEO into mesoporous silica particles. Further analysis indicated that the particle size and zeta potential of EONs were 717 ± 13.38 nm and − 43.90 ± 0.67 mV, respectively. Transmission electron microscopy (TEM) images showed that EONs had an inerratic morphology and stable structure. The bactericidal activities of PFEO and EONs against Escherichia coli (E. coli), Salmonella enterica (S. enterica), Staphylococcus aureus (S. aureus) and Listeria monocytogenes (L. monocytogenes) were subsequently tested using the twofold dilution method. Results indicated that, after 48 h incubation, minimum bactericidal concentrations (MBC) of EONs used against gram‐negative bacteria were decreased to a greater degree than those of PFEO, suggesting that nanoencapsulation by MCM‐41 can improve antimicrobial activity. Atomic force microscopy (AFM) observation also confirmed that EONs showed a notable inhibitory effect against E. coli by disrupting cell membrane structure. CONCLUSION: Pepper fragrant essential oil nanoencapsulation could be a very promising organic delivery system in food industry for antimicrobial activity enhancement. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

• Batch crystallisation of CaSO 4 was measured in the presence of mesoporous SiO 2. • Nanoparticles as seeds were found to enhance both nucleation and breakage. • Population balance model describing nucleation, growth, agglomeration and breakage. • Good agreement was found between experiments and model over a range of conditions. A population balance model is used to investigate the effect of mesoporous silica particles on calcium sulphate crystallisation in a stirred batch crystalliser. The model accounts for nucleation, growth, agglomeration, breakage, and particle-assisted nucleation, and the model equations are solved numerically using the method of classes over a logarithmic, non-uniform mesh. The crystallisation process is characterized experimentally using electrical conductivity to track the ion concentration and laser diffraction to measure the steady-state crystal size distribution obtained at the end of the experiments. The experiments are carried out over a range of temperatures, initial supersaturations, particle pore diameters, and particle loadings. The model is first fitted to experimental data obtained in the absence of particles to determine kinetic parameters of the nucleation, growth, agglomeration, and breakage for pure calcium sulphate crystallisation. Varying pore diameter did not influence the catalytic effect of the particles, however, particle loading was found to significantly decrease the nucleation induction time. The model was extended to account for the presence of particles by fitting two additional mechanisms. The first proposed a particle-assisted nucleation where nuclei are produced via heterogeneous crystallisation, then detach by particle-particle collision that is second-order with respect to particle loading. The second proposed that the crystal breakage frequency increases linearly with particle loading. Good agreement with the experimental data is demonstrated over the range of conditions examined. [ABSTRACT FROM AUTHOR]

Abstract Controlling the shape and size of mesoporous silica particles (MSPs) requires a deep understanding of the different parameters that play a major role during the synthesis of the materials. One of the key factors that can determine the morphology and porosity of the systems is the surfactant, used as a templating agent. We have very recently proven that binary mixtures of hexadecyltrimethylammonium bromide (CTAB) and bile salts are templating systems effective in controlling the morphology of MSPs in a facile and non-costly way. In this work we investigated the effect of different surfactant ratios in order to gain deeper insights on the influence of these catanionic mixtures on particle morphology. We employed mixtures of CTAB and sodium deoxycholate (NaDC) and upon variation of a sole parameter, the NaDC concentration, we achieved shape tuning. Hexagonal platelets, rods, oblate and toroidal particles were obtained and fully characterized. Moreover, investigation of the CTAB/NaDC assemblies showed that the morphology tuning is related to the evolution of the mixed micelles properties, occurring upon variation of the surfactant ratio. Graphical abstract Image 1 Highlights • Mesoporous silica particles (MSPs) were prepared using CTAB/NaDC mixtures. • Morphology tuning of MSPs was obtained varying only the NaDC concentration. • The evolution of the mixed micelle properties determines the shape variation. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Glabridin, a compound in the root extract of Glycyrrhiza glabra, has been identified as an effective tyrosinase inhibitor. Applied on skin, melanin synthesis is inhibited, making glabridin an interesting candidate for skin whitening or for the treatment of age spots. However, main obstaclefor its practical use is its low dermal bioavailability, caused by its poor water solubility. In this work smartPearls technology was used to increase the glabridins water solubility. smartPearls consist of silica particles with mesopores in which actives can be loaded. By this, actives are stabilized in amorphous state and simultaneously finely distributed in nm-range. Both amorphization and nanoization are well known approaches to increase saturation solubilities. In smartPearls these approaches are combined. In the first step, glabridin smartPearls formulation was developed, screening systematically the suitability of 4 different silicas varying in their pore sizes (3, 6, 10, 17 nm). Also, most suited filling level of glabridin was determined (25, 50, 80% referred to total pore volume of respective silica). Silica loading was performed by the immersion-evaporation method, resulting in pores filled with glabridin from bottom to top. By light microscopy, dynamic scanning calorimetry and X-ray diffraction the sample with 6 nm pore size and filling levels of 25% and 50% have been verified to be completely amorphous. Highest physical storage stability of 7 months up to now was obtained for the 25% filled sample. In the next step, concept of increased saturation solubility for smartPearls was proven. Dissolution profiles were recorded in situ for glabridin smartPearls and compared to glabridin raw drug powder. Both saturation solubility and dissolution velocity were remarkably improved. The water solubility for example increased by a factor of more than 4. This makes glabridin smartPearls promising for creating skin products with improved dermal bioavailability. [ABSTRACT FROM AUTHOR]

Various cosmetics having a single function are increasingly being used, but cosmetics having multifunctional activities remain limited. We aimed to develop a multifunctional cosmetic cream having antioxidant, anti-tyrosinase, anti-aging and antimicrobial activities. Antimicrobial activities were performed by disc-diffusion method. Cell toxicity and cell proliferations were evaluated in a 96-well plate with different cell lines such as HaCaT, RAW264.7, CCD-986Sk, B16F1, and B16F10. Mushroom tyrosinase inhibition, elastase inhibition, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities were evaluated and IC50 was calculated. Mesoporous silica particle was synthesized using Pluronic P123 and tetraethyl ortho-silicate (TEOS). Facial pictures were captured by VISIA-CR (Facial Imaging System for Clinical Research). Roughness of image was analysed by PRIMOS software and brightness of image was analyzed by Chromameter CR-400. The crude product of strain T65 inhibited the different human pathogenic bacteria such as Bacillus subtilis, Escherichia coli, Propionibacterium acnes, Staphylococcus aureus, Pseudomonas aeruginosa, and Staphylococcus epidermidis. The IC50 of T65 crude product for mushroom tyrosinase, elastase, and DPPH radical scavenging activities were 58.73, 14.68, and 6.31 µg/mL, respectively. T65 crude product proliferated collagen type I in CCD-986Sk cell up to 145.91% ± 9.11% (mean ± SD; mean of 24, 48, and 72 h) at 250 pg/mL. Synthesized mesoporous particles (SBA-15) confirmed the sustainable performance by control-release for three days. Formulated functional cosmetic cream containing T65 embedded SBA-15, significantly decreased the skin roughness by 4.670% and increased the skin brightness by 0.472% after application of 4 weeks. T65 crude product inhibited both Gram-positive and Gram-negative pathogens. Synthesized mesoporous particle, SBA-15, confirmed the physiologically active substance was released in sustainable release condition. T65 crude product showed impeccable antimicrobial, antioxidant, anti-aging, and whitening activities with non-cytotoxic effects to different cell lines related to the human skin.

The study was aimed to prepare a co-amorphous system of valsartan (VAL) with vanillin (VAN) for improving its solubility and dissolution followed by its confinement in mesoporous silica particles (MSPs) to stabilise the co-amorphous system and prevent its recrystallization. Amorphous VAL and VAN were obtained through quench-cooling and VAL/VAN binary co-amorphous system (VAL/VAN-CAS) was prepared through solvent evaporation technique. The particle size and morphology of VAL/VAN-CAS-MSPs were studied using scanning electron microscopy (SEM) and solid-state characterisation was performed by differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD). The in vitro dissolution was investigated by dialysis bag diffusion method. SEM analysis revealed irregular shaped VAL/VAN-CAS-MSPs with a size range of 5–25 μm, while outcomes of DSC and XRPD confirmed the formation of VAL/VAN-CAS. The in vitro dissolution profiles demonstrated a significantly increased dissolution in first 60 minutes from VAL/VAN-CAS (∼68%) and VAL/VAN-CAS-MSPs (∼76%) compared to powder VAL (∼25%). [ABSTRACT FROM AUTHOR]

Mesoporous silica particles of type MCM-41 (Mobile Composition of Matter No. 41), exhibiting highly ordered mesoporosity (pores with diameter between 2 and 50 nm) and surface roughness, are developed and used as a functional coating on bioactive glass-based scaffolds for bone tissue engineering. The degradability and the mesostructure stability of these novel MCM-41 particles were evaluated. The particles are immersed in simulated body fluid (SBF) for up to 28 days at 37 °C, and the variation of the ordered porosity, surface characteristics, and chemical composition of the particles are assessed by SEM-EDX, HRTEM, FTIR, ICP-OES, and pH measurements. The results indicate that the MCM-41 particles are affected by immersion in SBF only during the first few days; however, the surface and the mesopore structure of the particles do not change further with increasing time in SBF. The pore channel diameter increased slightly, confirming the stability of the developed material. The release of dissolved Si-species, which reached a maximum of 260 mg SiO2 per gram of material, could play a key role in gene activation of osteoblast cells and in inducing new bone matrix formation. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate that preparation by electrospray deposition of mesoporous SiO2 particles can be employed as additives to Aluminum/Poly (Vinylidene Fluoride) (Al/PVDF) to enhance reaction velocity. We find that the reaction velocity of Al/PVDF with 5 wt% SiO2 is 3× higher. The presence of meso‐SiO2 appears to accelerate the decomposition of PVDF, with a significant increase in HF release, resulting in higher heat release. We believe that hot‐spots around meso‐SiO2 may serve as multiple ignition points, with the multi‐layered structure promoting heat convection to increase the propagation rate. [ABSTRACT FROM AUTHOR]

The addition of hydrophilic components (CaCl 2 , poly-2-ethyl-2-oxazoline (PEOX) or mesoporous silica particles (MSP)) into Styrene-Butadiene-Styrene (SBS)/chloroform solution was shown to affect the resulting breath figure patterns in terms of pore size, pore shape and order. Honeycomb-patterned porous SBS polymer films were prepared by adding 30 wt% PEOX capped, CaCl 2 loaded mesoporous silica particles into SBS solution. The long-range order observed with a pore diameter of ∼3.6 µm in the breath figure pattern at RT and 50–70% RH was attributed to the synergistic contributions of each component. CaCl 2 promotes the condensation of water vapor and the nucleation of many water droplets on the polymer solution. When localized in a uniformly swollen layer of PEOX around MSP, easier nucleation together with stabilization of water droplets by MSP and PEOX leads to hexagonally-ordered breath figures. The results demonstrate the addition of hydrophilic components as an easy tool to tune breath figure patterns at relatively low humidity and their synergistic contributions. [Display omitted] [ABSTRACT FROM AUTHOR]

This study prepared novel curcumin formulation using mesoporous silica particles (MPSPs) and investigated the in vitro penetration through the skin and in vivo antiinflammatory and analgesic effects. The loading of curcumin into MPSPs was very efficient (98.72%). An in vitro skin permeation study showed that MPSPs significantly enhanced curcumin penetration through the rabbit skin in a linear diffusion pattern. Anti-inflammatory study using formalin induced mouse oedema assay clearly showed that curcumin encapsulated into MPSPs had anti-inflammatory effect, while analgesic effect was carried out using the standard Eddy's hot plate assay. Curcumin formulation showed higher analgesic activity compared to the placebo as indicated by higher response time (licking forepaws) but this difference was statistically insignificant (p > 0.05).

Diseases in the respiratory tract rank among the leading causes of death in the world, and thus novel and optimized treatments are needed. The lungs offer a large surface for drug absorption, and the inhalation of aerosolized drugs are a well-established therapeutic modality for local treatment of lung conditions. Nanoparticle-based drug delivery platforms are gaining importance for use through the pulmonary route. By using porous carrier matrices, higher doses of especially poorly soluble drugs can be administered locally, reducing their side effects and improving their biodistribution. In this study, the feasibility of mesoporous silica particles (MSPs) as carriers for anti-inflammatory drugs in the treatment of airway inflammation was investigated. Two different sizes of particles on the micron and nanoscale (1 µm and 200 nm) were produced, and were loaded with dexamethasone (DEX) to a loading degree of 1:1 DEX:MSP. These particles were further surface-functionalized with a polyethylene glycol–polyethylene imine (PEG–PEI) copolymer for optimal aqueous dispersibility. The drug-loaded particles were administered as an aerosol, through inhalation to two different mice models of neutrophil-induced (by melphalan or lipopolysaccharide) airway inflammation. The mice received treatment with either DEX-loaded MSPs or, as controls, empty MSPs or DEX only; and were evaluated for treatment effects 24 h after exposure. The results show that the MEL-induced airway inflammation could be treated by the DEX-loaded MSPs to the same extent as free DEX. Interestingly, in the case of LPS-induced inflammation, even the empty MSPs significantly down-modulated the inflammatory response. This study highlights the potential of MSPs as drug carriers for the treatment of diseases in the airways.

In this research, a novel IMAC sorbent with high specificity for chlorine-containing compounds was developed. Ni-functionalized monodisperse spherical mesoporous silica particles of 500 ± 25 nm diameter were synthesized and their metal affinity properties were studied with the use of diclofenac as the model substance. The particles were aggregatively stable in the pH range of 3–12. The sorbent demonstrated a high adsorption capacity (0.60 ± 0.06 μg of DCF per 1 mg of the sorbent) and high adsorption/desorption rate (20 and 5 min was enough for the sorbent saturation and desorption of DCF, correspondingly). A mixture of eluents with addition of PFOS providing the almost complete recovery (98%) of diclofenac was first proposed. The monodispersity and the high sedimentation and aggregative stability of the particles provide the formation of a stable hydrosol even under ultrasound treatment which makes the mSiO 2 /Ni particles suitable for batch chromatography. [ABSTRACT FROM AUTHOR]

Folic acid (FA) is a synthetic vitamin commonly used for food fortification. However, its vulnerability to processing and storage implies loss of efficiency, which would induce over-fortification by processors to obtain a minimum dose upon consumption. Recent studies have indicated potential adverse effects of FA overdoses, and FA protection during processing and storage could lead to more accurate fortification. In addition, sustained vitamin release after consumption would help improve its metabolism. The objective of this work was to study controlled FA delivery and stability in fruit juices to reduce potential over-fortification risks by using gated mesoporous silica particles (MSPs). The obtained results indicated that FA encapsulation in MSPs significantly improved its stability and contributed to controlled release after consumption by modifying vitamin bioaccessibility. These results confirmed the suitability of MSPs as support for controlled release and protection of bioactive molecules in food matrices in different food production and storage stages. [ABSTRACT FROM AUTHOR]

The effect of the phosphoric acid addition on the nanostructures of the mesoporous silica (MPS) particles and the states of tris(8-hydroxyquinolinato)aluminum (Alq 3) in the mesopores were investigated. It was found that the regularity of the mesopores of the MPS particles became irregular by the excessive addition of phosphoric acid. Furthermore, the phosphoric acid on the silica skeletons in the mesopores would strictly interact with the Alq 3 molecules, so that the proportion of monomer components with less overlap among the π - π orbitals (i.e., δ -phase-like Alq 3 molecules) increased with increasing the phosphoric acid, which was effectively monitored in the fluorescence spectra. It was suggested that the interactions between Alq 3 and mesopores were formed not only by hydrogen bonds but also by electrostatic forces between P–O− and aluminum ion, and then the Alq 3 molecules were planarly fixed on the surfaces, indicating the importance of the phosphoric acid addition for fixing the photofunctional species on the mesopores. [Display omitted] • Phosphoric acid-containing mesoporous silica (PMPS) particles were synthesized. • Tris(8-hydroxyquinolinato)aluminum (Alq 3) was adsorbed on the mesopores. • Characteristic nanostructures of the particles were analyzed and investigated. • Alq 3 strongly interacted with the mesopores containing phosphoric acid. • The monomer component of Alq 3 increased with increasing the phosphoric acid. [ABSTRACT FROM AUTHOR]

Hexahistidine-tagged organophosphate hydrolase (His-OPH), an organophosphate degrading enzyme, immobilised by physical adsorption and covalent binding methods on mesoporous silica (MPS) particles, was examined as a biocatalyst for organophosphate hydrolysis within an aqueous medium and for providing an efficient tool in the detection/detoxification of paraoxon. His-OPH was immobilised on mesoporous silica particles of different pore size distributions (10-40 and 6 nm) and sizes (5 μm and 500 nm), through covalent attachment and physical adsorption. The biocatalysts showed good activities and enhanced stabilities with respect to the free enzymes, depending on the material and used immobilisation technique. Graphical Abstract: Biomaterial based on hexahistidine-tagged organophosphorus hydrolase (His-OPH) was developed by enzyme immobilisation into/onto two types of silica particles with different porosity. While adsorbed enzymes showed higher activities, covalent attached enzymes showed minimal or no losses in activity as well as reusability. [ABSTRACT FROM AUTHOR]

Mesoporous silica particles (MSPs) are considered suitable supports to design gated materials for the encapsulation of bioactive molecules. Folates are essential micronutrients which are sensitive to external agents that provoke nutritional deficiencies. Folates encapsulation in MSPs to prevent degradation and to allow their controlled delivery is a promising strategy. Nevertheless, no information exists about the protective effect of MSPs encapsulation to prevent their degradation. In this work, 5-formyltetrahydrofolate (FO) and folic acid (FA) were entrapped in MSPs functionalized with polyamines, which acted as pH-dependent molecular gates. The stability of free and entrapped vitamins after acidic pH, high temperature and light exposure was studied. The results showed the degradation of FO after high temperature and acidic pH, whereas entrapped FO displayed enhanced stability. Free FA was degraded by light, but MSPs stabilized the vitamin. The obtained results point toward the potential use of MSPs as candidates to enhance stability and to improve the bioavailability of functional biomolecules. [ABSTRACT FROM AUTHOR]

Mesoporous silica materials have the ability to entrap drugs, nutrients and functional biomolecules and can be able to act as smart delivery systems capable to control and target the release of their cargo in a particular part of the gastrointestinal tract when administrated orally. However, the aptness of these encapsulation supports in in vivo oral controlled release relies on their chemical stability through the digestive tube. In this context, we have evaluated the stability of four different mesoporous silica particles, frequently used as encapsulating supports, during an in vitro digestion process comprising buccal, stomach and intestinal phases. Results showed that after 4 h of digestion, the textural properties of silica supports in the form of nanoparticles (MCM-41 and UVM-7 nanoparticles) were lost in varying degrees, whereas silica microparticles supports (MCM-41 and SBA-15 microparticles) endures better the digestion process. Moreover, the functionalization of the surface with N 1 -(3-trimethoxysilylpropyl)diethylenetriamine, an organic moiety commonly used in the preparation of pH-responsive mesoporous silica particles, resulted in an improvement of the stability of the supports. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles were synthesized by using tannic acid as a pore-forming agent, which is an environmentally friendly, cheap, and non-surfactant template. SEM and TEM images indicated that the tannic acid-templated mesoporous silica nanoparticles (TA-MSNs) are monodisperse spherical-like particles with an average diameter of 195 ± 16 nm. The Brunauer-Emmett-Teller (BET) results showed that the TA-MSNs had a relatively high surface area (447 m/g) and large pore volume (0.91 cm/g), and the mean pore size was ca. 10.1 nm. Burkholderia cepacia lipase was immobilized on the TA-MSNs by physical adsorption for the first time, and the properties of immobilized lipase (BCL@TA-MSNs) were investigated. The BCL@TA-MSNs exhibited satisfactory thermal stability; strong tolerance to organic solvents such as methanol, ethanol, isooctane, n-hexane, and tetrahydrofuran; and high operational reusability when BCL@TA-MSNs were applied in esterification and transesterification reactions. After recycling 15 times in the transesterification reaction for biodiesel production, over 85 % of biodiesel yield can be maintained. With these desired characteristics, the TA-MSNs may provide excellent candidates for enzyme immobilization. [ABSTRACT FROM AUTHOR]