Mesoporous Silica Nanocomposites Research Articles

Origin of selectivity in surface functionalized vinylpyridine mesoporous silica nanocomposites (VP/SBA) for Henry reaction

Origin of selectivity in surface functionalized vinylpyridine mesoporous silica nanocomposites (VP/SBA) for Henry reaction

Enhanced photocatalytic removal of methyl orange dye employing SiO2/Mn2O3 based nanocatalyst under visible light

Surface water contamination by dye pollutants is a global environmental concern. The treatment of effluent from textile waste using metal oxide-based photocatalysts is a widely employed approach owing to its efficacy and simplicity. Herein, the synthesis and fabrication of novel visible radiation receptive manganese oxide and mesoporous silica nanocomposites (Mn2O3/SiO2) is described. Surface morphology of nanocomposites using scanning electron microscopy (SEM) displayed spherical shaped agglomerated structure. The chemical composition of nanocomposites was examined by using energy dispersive x-ray (EDX) analysis respectively indicating the presence of respective elements. Structural analysis was carried out by using XRD spectroscopy, while optical properties were evaluated by employing UV–visible spectroscopy. The photocatalytic activity of pure Mn2O3 and SiO2 nanoparticles as well as their nanocomposites with two different ratios Mn2O3/SiO2 (1:3) and Mn2O3/SiO2 (3:1) were evaluated by using methyl orange (MO) as a model dye. The band gap energy of Mn2O3/SiO2 (1:3) and Mn2O3/SiO2 (3:1) nanocomposite was 2.39 eV and 1.69 eV respectively. The nanocomposites exhibited improved photocatalytic efficiency as compared to pure nanoparticles as a function of pH and mixing ratio. For instance, at pH 7.0, Mn2O3/SiO2 (1:3) nanocomposite has depicted maximum degradation efficiency of 68 % for degradation of MO as compared to Mn3O4/SiO2 (3:1) nanocomposite, Mn3O4 and SiO2 nanoparticles. However, at pH 2.0 Mn2O3/SiO2 (3:1) nanocomposite had shown maximum degradation efficiency of 99 % as compared to Mn2O3/SiO2 (1:3), Mn2O3 and SiO2 nanoparticles. The degradation reaction followed pseudo first order kinetics. At pH 7.0, the rate constant values of nanocomposites i.e. Mn2O3/SiO2(1:3) and Mn2O3/SiO2(3:1) comes out to be 4.68 × 10−3 min−1 and 2.49 × 10−3 min−1 respectively. At pH 2.0, the rate constant values calculated for Mn2O3/SiO2(1:3) nanocomposite and Mn2O3/SiO2(3:1) nanocomposite was 4.91 × 10−3 min−1 and 1.24 × 10−2 min−1 respectively. The easy fabrication of these nanocomposites coupled with facile tuning of their properties make them suitable contenders for efficient dye degradation in wastewater treatment.

Magnetic Mesoporous Silica Nanocomposite Supported Ionic Liquid/Cu as a Powerful and Highly Stable Catalyst for Chan-Lam Coupling Reaction

Magnetic Mesoporous Silica Nanocomposite Supported Ionic Liquid/Cu as a Powerful and Highly Stable Catalyst for Chan-Lam Coupling Reaction

Simple thermal treatment to improve the MRI and magnetic hyperthermia performance of hybrid iron Oxide-Mesoporous silica nanocarriers

The design of multifunctional nanocomposites (NCs), incorporating a variety of controllable properties from nanostructured materials, spans their applicability as nanotools in biomedical applications. Santa Barbara Amorphous (SBA-15) mesoporous silica has showcased remarkable capabilities, ranging from bone regeneration to drug delivery. Its synergy with magnetic nanoparticles (MNPs) further broadens its scope as a theranostic agent, seamlessly integrating both therapeutic and diagnostic functions. However, efficiency issues arise due to MNP anchoring, necessitating novel solutions for optimization. This study focuses on enhancing the magnetic properties of hybrid iron oxide-SBA-15 mesoporous silica NCs through a simplified thermal procedure. The aim is to optimize their magnetic performance for dual functionality as contrast agents for magnetic resonance imaging (MRI) and as effective heaters in magnetic hyperthermia (MH) processes, while preserving the cylindrical mesoporous structure, high surface area, and high loading capacity compared to conventional ceramics. The investigation highlights that the impact of heat treatment on physicochemical properties varies depending on the compositions of the NCs. Specifically, the transversal relaxivity in MRI was doubled, accompanied by an enhanced Néel contribution in MH. This enhancement was achieved while maintaining the same biocompatibility as non-treated NCs, as demonstrated in evaluations with two cancer cell lines (HeLa and T-731 astrocytes), revealing low toxicity at concentrations up to 200 μg/mL.

Enhancing the inhibition of dental erosion and abrasion with quercetin-encapsulated hollow mesoporous silica nanocomposites.

Introduction: Dental erosion and abrasion pose significant clinical challenges, often leading to exposed dentinal tubules and dentine demineralization. The aim of this study was to analyse the efficacy of quercetin-encapsulated hollow mesoporous silica nanocomposites (Q@HMSNs) on the prevention of dentine erosion and abrasion. Method: Q@HMSNs were synthesized, characterized, and evaluated for their biocompatibility. A total of 130 dentine specimens (2mm × 2mm × 2mm) were prepared and randomly distributed into 5 treatment groups (n = 26): DW (deionized water, negative control), NaF (12.3mg/mL sodium fluoride, positive control), Q (300μg/mL quercetin), HMSN (5.0mg/mL HMSNs), and Q@HMSN (5.0mg/mL Q@HMSNs). All groups were submitted to in vitro erosive (4 cycles/d) and abrasive (2 cycles/d) challenges for 7days. The specimens in the DW, NaF, and Q groups were immersed in the respective solutions for 2min, while treatment was performed for 30s in the HMSN and Q@HMSN groups. Subsequently, the specimens were subjected to additional daily erosion/abrasion cycles for another 7days. The effects of the materials on dentinal tubule occlusion and demineralized organic matrix (DOM) preservation were examined by scanning electron microscopy (SEM). The penetration depth of rhodamine B fluorescein into the etched dentine was assessed using confocal laser scanning microscopy (CLSM). The erosive dentine loss (EDL) and release of type I collagen telopeptide (ICTP) were measured. The data were analysed by one-way analysis of variance (ANOVA) with post hoc Tukey's test (α = 0.05). Results: Q@HMSNs were successfully synthesized and showed minimal toxicity to human dental pulp stem cells (HDPSCs) and gingival fibroblasts (HGFs). Q@HMSNs effectively occluded the dentinal tubules, resulting in a thicker DOM in the Q@HMSN group. The CLSM images showed more superficial penetration in the HMSN and Q@HMSN groups than in the quercetin, NaF, and DW groups. The Q@HMSN group exhibited a significantly lower EDL and reduced ICTP levels compared to the other groups (p < 0.05). Conclusion: Q@HMSNs hold promise for inhibiting dentine erosion and abrasion by promoting tubule occlusion and DOM preservation.

Investigation on the physicochemical properties of poly (ethylene-co-vinyl acetate)/mesoporous silica nanocomposites: Effects of content and surface functionalization

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.

Enhanced Photocatalytic Degradation of Tetracycline-Class Pollutants in Water Using a Dendritic Mesoporous Silica Nanocomposite Modified with UiO-66

Enhanced Photocatalytic Degradation of Tetracycline-Class Pollutants in Water Using a Dendritic Mesoporous Silica Nanocomposite Modified with UiO-66

Natural Rubber/Hexagonal Mesoporous Silica Nanocomposites as Efficient Adsorbents for the Selective Adsorption of (-)-Epigallocatechin Gallate and Caffeine from Green Tea.

(-)-Epigallocatechin gallate (EGCG) is a bioactive component of green tea that provides many health benefits. However, excessive intake of green tea may cause adverse effects of caffeine (CAF) since green tea (30-50 mg) has half the CAF content of coffee (80-100 mg). In this work, for enhancing the health benefits of green tea, natural rubber/hexagonal mesoporous silica (NR/HMS) nanocomposites with tunable textural properties were synthesized using different amine template sizes and applied as selective adsorbents to separate EGCG and CAF from green tea. The resulting adsorbents exhibited a wormhole-like silica framework, high specific surface area (528-578 m2 g-1), large pore volume (0.76-1.45 cm3 g-1), and hydrophobicity. The NR/HMS materials adsorbed EGCG more than CAF; the selectivity coefficient of EGCG adsorption was 3.6 times that of CAF adsorption. The EGCG adsorption capacity of the NR/HMS series was correlated with their pore size and surface hydrophobicity. Adsorption behavior was well described by a pseudo-second-order kinetic model, indicating that adsorption involved H-bonding interactions between the silanol groups of the mesoporous silica surfaces and the hydroxyl groups of EGCG and the carbonyl group of CAF. As for desorption, EGCG was more easily removed than CAF from the NR/HMS surface using an aqueous solution of ethanol. Moreover, the NR/HMS materials could be reused for EGCG adsorption at least three times. The results suggest the potential use of NR/HMS nanocomposites as selective adsorbents for the enrichment of EGCG in green tea. In addition, it could be applied as an adsorbent in the filter to reduce the CAF content in green tea by up to 81.92%.

Evaluation and correlation of self-healing functionalized silane-based hybrid nanocomposite materials as corrosion inhibitor

Benzimidazole is a widely used compound exhibits intriguing networking capabilities. In this study, we synthesized and characterized mesoporous silica nanocomposites loaded with benzimidazole on reduced graphene oxide (GOSB). We investigated the impact of these composites on the long-term corrosion rate control of steel surfaces in aqueous solutions. The novel material's formation and behavior in the aqueous solution were assessed through comprehensive multi-technique analyses. The corrosion inhibition efficiency of GOSB was found to be remarkably high, with values of 98.07% and 99.29% determined from electrochemical impedance spectroscopy and potentiodynamic polarization studies, respectively. The superior protection observed on the steel surface in the aqueous GOSB solution can be attributed to the synergistic effects of two distinct surface layers and solution-based mechanisms. The interaction between the d-π* orbitals of the steel surface and benzimidazole molecules within GOSB emerges as the primary contributor to the formation of the protective layer. This straightforward solution-based approach opens up new avenues for future research in the realm of industrial corrosion prevention and coating.

In vitro and Bioimaging Studies of Mesoporous Silica Nanocomposites Encapsulated Iron-oxide and Loaded Doxorubicin Drug (DOX/IO@Silica) as Magnetically Guided Drug Delivery System.

In recent years, the delivery of drugs by nanocomposites has emerged as an exciting field of research for bio-imaging tools and targeted cancer treatment. The large surface area and porous volume of mesoporous silica nanocomposites (MSN's) have gained a lot of interest for their application in the delivery of drugs and the magnetic properties of iron oxide (IO) nanocomposites play a key role in the targeted delivery system. In this study, mesoporous silica encapsulated IO nanocomposites loaded with doxorubicin (DOX) were synthesized for the magnetically guided delivery of anticancer drugs. The synthesis of IO nanocomposites was done through the precipitation method, and then silica encapsulation and drug loading were done by the StÖber method. The magnetically driven delivery of the drug is produced by the encapsulation of magnetically active IO in the mesoporous silica shell. The controlled release of DOX is possible because of the MSN's. TEM images show that the nanocomposites have a spherical morphology and average diameter in the range of 120 nm. Power-XRD data confirm the crystalline nature of nanocomposites. The strong absorption peak was observed in UV-Visible spectroscopy at 490 nm and quenching in fluorescence spectra confirms the encapsulation of DOX in the mesoporous silica shell. VSM data showed the magnetic nature of nanocomposites, with large magnetic susceptibility (74.88 emu/g). The use of DOX/IO@Silica nanocomposites as a sustainable drug release and targeted drug delivery vehicle has been reported here. The pH dependent release of DOX was studied and significant release was observed at lower pH. In-vitro cell viability assay and fluorescence imaging assay have demonstrated that these nanocomposites show significant dose-dependent toxicity to cancer cells in the presence of a magnetic field. In-vitro studies via the MTT assay showed that these synthesized nanocomposites in culture are non-toxic to healthy cells compared to DOX-induced cytotoxicity due its controlled release and can be further strengthened by magnetic guidance. Therefore, due to its optical properties and potential for guided delivery of drug to the targeted site, these nanocomposites are ideal as an anticancer agent and bio-imaging prob.

CoFe2O4 decorated graphene/C18-functionalized mesoporous silica nanocomposites prepared for magnetic enrichment and electrochemical detection of promethazine in beef

Promethazine (PHZ) is used as a sedative in veterinary medicine, and its residue can threaten the health of human. The electrochemical detection of PHZ is suitable method for application in the field. However, the traditional electroanalysis is difficult to perform directly in meat samples due to matrix interference. This work integrates magnetic solid-phase extraction and differential pulse voltammetry for highly sensitive and selective determination of PHZ in beef and beef liver for the first time. CoFe2O4/graphene coated with C18-functionalized mesoporous silica (MG@mSiO2-C18) is synthesized as dispersed magnetic adsorbent to extract PHZ. Magnetic glassy carbon electrode modified with nitrogen-doped hollow carbon microspheres (HCM) attracts the MG@mSiO2-C18 with PHZ, and directly detects the PHZ without elution procedure. MG@mSiO2-C18 can separate PHZ to avoid the interference of impurities on following detection, and also concentrate PHZ on magnetic electrode. Additionally, the electrode modification with HCM can amplify the electrochemical signal of PHZ. Finally, the integrated PHZ determination method exhibits a wide linear range from 0.08 µmol/L to 300 µmol/L with a low limit of detection of 9.8 nmol/L. The beef sample analysis presents excellent recovery, demonstrating that this protocol is promising for the rapid and onsite detection of PHZ in real meat samples

Synergic fabrication of hybrid nanocapsules gold-organosilica for MRI-guided photothermal-enhanced synergistic effect chemodynamic lung cancer therapy

In contrast to the typical template-based multistep approach for constructing multi-functional mesoporous hollow silica nanocomposites (MHSN), a simple and template-free fabricate system has been developed to develop versatile mesoporous hollow silica nanocapsules (OSNs) encompassing together isopentyl acetate (IsA) solution and AuNPs. This new material has tiny and homogeneous particle sizes (∼82 nm), a large surface area (535 m2 g−1), and remarkable colloidal durability in water. The oil-phase IsA with high volatility and a low boiling point (142 °C) is critical in building bulky hollow cavities from structural strategy. It allows the IsA@OSNs to become an effective development mediator in the ablation of high-intensity focused ultrasound (HIFU) treatment. Furthermore, the distinctive satellite-like dispersion of Gold (AuNPs) on the silica shell provided IsA@OSNs with outstanding magnetic resonance imaging (MRI) contrasts in A549 lung cells in vitro and in vivo. Furthermore, such unique theranostics agents have excellent systemic toxicity, which promises well for promising clinical use in MRI-piloted HIFU treatment.

Synergic fabrication of folic acid-targeted hyperbranched polymer (HBP)-modified pH-response drug delivery system for the treatment of breast cancer

As vectors for anticancer drug delivery, mesoporous silica nanocomposites (MSN) incorporated bicalutamide (BLT) featuring folic acid (FA) (termed as COOH-MSNs-HBP@BLT/FA) have been effectively achieved due to their ability to pH stimulation response and targeting. Systematic characterization investigations were conducted to determine the chemical composition and physical characteristics of these NPs. Through carboxy alteration, their drug loading capacity was dramatically increased (268.60 %), and they displayed pH-responsive drug release patterns. Additionally, the cytotoxicity of the as-synthesized NPs was tested in MDA-MB-231 and MCF-7 cells in vitro. After 24-h of treatment with BLT, COOH-MSNs, COOH-MSNs@BLT, COOH-MSNs-HBP@BLT/FA, MCF-7, and MDA-MB-231 cells exhibited distinct morphological alterations, and reddish orange apoptotic bodies were detected using acridine orange and ethidium bromide (AO and EB) double staining. Nuclear alterations such as chromatin condensation/fragmentation were detected by Hoechst 33342 staining techniques. The Annexin V-FITC/PI was used to examine the apoptosis mechanism of the cells. These results prove that apoptosis induction is responsible for the antiproliferative effects of BLT, COOH-MSNs, COOH-MSNs@BLT, and COOH-MSNs-HBP@BLT/FA in MCF-7 and MDA-MB-231cells. We conclude that COOH-MSNs-HBP@BLT/FA has the potential as a drug delivery method for breast cancer treatment.

Magnetic Carbon Nanotubes Mesoporous Silica Nanocomposite Functionalized with Palladium: Synthesis, Characterization, and Application as an Efficient Catalyst for Suzuki–Miyaura Reactions

Magnetic Carbon Nanotubes Mesoporous Silica Nanocomposite Functionalized with Palladium: Synthesis, Characterization, and Application as an Efficient Catalyst for Suzuki–Miyaura Reactions

Synthesis and characterization of hollow mesoporous silica nanocomposites containing phosphorescent pigment and doxycycline

AbstractHollow mesoporous silica can be used as a carrier to store large amounts of drugs in pharmaceuticals due to its high surface area and suitable porosity. Therefore, the purpose of this study was to develop a SrAl2O4:Eu2+,Dy3+ hollow mesoporous silica and apply for loading and tracking of doxycycline (DOX) release. The structure and particle morphology were investigated by X‐ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM) pictures, respectively. Photoluminescence (PL) spectra revealed that the phosphors had efficient luminescent and long‐lasting properties. Finally, according to the obtained results, the amount of drug loading in hollow mesoporous regular silica was 35% and the drug release from hollow mesoporous regular silica was gradual and controlled.

Characterization and antifungal applications of azole functional mesoporous and hollow silica nanocomposites

Bu çalışmada çok gözenekli (MSN) ve tek gözenekli (HSS) silika nanopartiküllerin yüzeyinde, viniltriazol (VTri) monomerinin polimerizasyon reaksiyonu ile amin grupları oluşturulmuştur. Hazırlanan nanokompozit yapıların karakterizasyonu ve antifungal özelliği incelenmiştir. Nanokompozitlerin karakterizasyonunda MSN ve HSS' nın viniltriazol ile etkileşimini, yüzeydeki azol gruplarının varlığını belirlemek için FTIR ve XRD analizi, termal özelliklerini incelemek için TGA analizi yapılmıştır. Nanokompozitlerin morfolojisini belirlemek için SEM analizi yapılmıştır. Nanokompozit yapıların antifungal özellikleri MİK yöntemi ile kanıtlanmıştır.

Synthesis of MCM‐41@SO3H‐Polymixin B Nanocomposite for Extraction and Determination of Lipopolysaccharide from Aqueous Solutions using Taguchi Fractional Factorial Design

AbstractLipopolysaccharide (LPS) is a component of Gram‐negative bacteria‘s outer membrane that, when released into aqueous solutions, can have devastating consequences for human health. In this study, sulfonic acid‐functionalized mesoporous silica nanocomposites bound to polymixin‐B was synthesized and their functionality to absorb the bacterial LPS from human serum was investigated. Briefly, Pseudomonas aeruginosa was isolated from burn wounds and its LPS was extracted. Then, Mesoporous MCM‐41 nanocomposites were fabricated and functionalized with the sulfonic acid groups. Finally, nanocomposites were used to extract LPS from human serum and statistical data were analyzed using the Taguchi method. Extraction of bacterial LPS with a modified method, optimization of factors affecting the extraction of endotoxin using Taguchi method, introduction of new nano‐composites with nanometer pores and obtaining results with 96 % effectiveness in removing LPS in LAL and MTT tests were the most important findings. The obtained calibration curve was linear in the ranges of 1–300 μg L‐1 with reasonable linearity (r2&gt;0.998). The limit of detection (LOD) based on S/N=3 was 0.03 μg L‐1 for 10 mL sample volumes.

Multifunctional Folic acid‐coated and Doxorubicin Encapsulated Mesoporous Silica Nanocomposites (FA/DOX@Silica) for Cancer Therapeutics, Bioimaging and invitro Studies

AbstractCancer is a cluster of diseases, which caused by the mutation in cells and it has the potential to cover any part of the body. The whole world is vigorously struggling to find a safe approach to cure the cancer. The classical chemotherapy approach involves the use of chemotherapeutic agents to kill cancer cells. The major disadvantage of therapy is less in vivo stability and negatively affects the healthy cells. Nowadays, the targeted drug delivery techniques has gained lots of interest, because of the efficient drug release at the cancerous sites. Herein, we have synthesized Folic acid (FA) coated and Doxorubicin drug (Dox) encapsulated mesoporous silica nanocomposites (FA/Dox@Silica)for targeted delivery of DOX and bioimaging. Encapsulation of Dox was done to make it more stable in the cell atmosphere and for its controlled release. The coating of FA makes these nanocomposites makes them an vehical for chemically targeted delivey of DOX, as it was already confirmed by several studies that there are folate receptors present over cancer cells and these reseptors are responsive towards the FA Thus these nanocomposites can be easily recognized by the cancer cells and they can efficiently deliver drugs. The shape, size, morphology, crystallinity, porosity, and fictionalizations were analyzed by using several characterization techniques such as DLS, TEM, and FTIR. The drug loading was confirmed qualitatively by using optical spectroscopic techniques. The drug release pattern was studiedfor the 15 days which showed the sustained and regulated release of drug from the mesoporous silica nanocomposites. Cellular uptake was observed by cell staining assay confirmed the fair uptake of nanoparticles.

Carbon-based nanocomposite materials with multifunctional attributes for environmental remediation of emerging pollutants.

Carbon-based materials are among the most biosynthesized nanocomposites with excellent tunability and multifunctionality features, that other materials fail to demonstrate. Naturally occurring materials, such as alginate (Alg), can be combined and modified by linking the active moieties of various carbon-based materials of interest, such as graphene oxide (GO), carbon nanotubes (CNTs), and mesoporous silica nanocomposite (MSN), among others. Thus, several types of robust nanocomposites have been fabricated and deployed for environmental remediation of emerging pollutants, such as pharmaceutical compounds, toxic dyes, and other environmentally hazardous contaminants of emerging concern. Considering the above critiques and added features of carbon-based nanocomposites, herein, an effort has been made to spotlight the synergies of GO, CNTs, and MSN with Alg and their role in mitigating emerging pollutants. From the information presented in this work, it can be concluded that Alg is a material that has excellent potential. However, its use still requires further tests in different areas and other materials to carry out a holistic investigation that exploits its versatility for environmental remediation purposes.

Contemporary, Multidisciplinary Roles of Mesoporous Silica Nanohybrids/Nanocomposites

AbstractNumber of nanomaterials have been produced as a result of the growth of nanoscience and nanotechnology, and have found applications in interdisciplinary sectors in which nanotechnology has now become indispensable. Owing to the better properties over individual nanomaterials, the hybrid materials have been broadly studied. Mesoporous silica nanoparticles (MS Nps) have been employed as a matrix in the synthesis of nanohybrids and as a filler in nanocomposites due to its high porosity, adjustable pore volume, facile functionalization, thermal and chemical stability and less toxicity. So far, versatile MS Nps hybrids and composites have been synthesized as advanced smart materials to be applied across industrial and biological sectors. This review study gives an up‐to‐date viewpoint on the synthesis and uses of mesoporous silica nanohybrids and nanocomposites particularly in biomedical sectors, agricultural and food industries and in environmental remediation followed by future insights and research directions of MS Np hybrids and composites.