Mesoporous Silica Research Articles

Dendritic mesoporous silica loaded with gold nanoclusters and their application in immunochromatographic assay.

Novel green-emitting fluorescent microspheres (GreFMPs) were assembled by loading highly luminescent gold nanoclusters (Arg/ATT/AuNCs) ondendritic mesoporous silica nanoparticles (DMSNs) via PEI-mediated electrostatic adsorption. The fluorescence microspheres exhibit excellent monodispersion with average diameters about (254.5 ± 34.6nm). Compared with free Arg/ATT/AuNCs, the GreFMPs have similar fluorescent properties and biocompatibility but superior environmental tolerance. Subsequently, an immunochromatographic assay based on GreFMPs (GreFMP-ICA) has been successfully developed, which is highly selective toward alphafetoprotein (AFP) in human serum. Under the optimal parameters, there is a good linear range between 0.5 and 160.0ng/mL, the limit of detection was found to be about 0.5ng/mL, and the recovery and relative standard deviation are 81.0 ~ 100.6% and 3.5 ~ 16.6%, respectively. These results manifested that the GreFMPs are beneficial for the rational design of the ICA platform, and the proposed GreFMP-ICA has the potential to screen AFP in clinical applications.

Enhanced Gallium Extraction Using Silane-Modified Mesoporous Silica Synthesized from Coal Gasification Slag

This study presents an innovative approach to utilize coal gasification coarse slag (CGCS) for efficient and low-cost gallium extraction. Using a one-step acid leaching process, mesoporous silica with a surface area of 258 m2/g and a pore volume of 0.15 cm3/g was synthesized. The properties of CGCS before and after acid leaching were characterized through SEM, FTIR, XRD, and BET analyses, with optimal conditions identified for maximizing specific surface area and generating saturated silanol groups. The prepared mesoporous silica demonstrated a 99% Ga(III) adsorption efficiency. Adsorption conditions were optimized, and adsorption kinetics, isotherms, and competitive adsorption behaviors were evaluated. Competitive adsorption with vanadium suggests potential application in Ga(III) extraction from vanadium-rich waste solutions. Furthermore, the recyclability of both the acid and adsorbent was explored, with the adsorbent maintaining over 85% adsorption efficiency after five cycles. The adsorption mechanism was further elucidated through SEM-EDS, XPS, and FTIR analyses. This work not only advances resource recovery from industrial waste but also offers a sustainable method for gallium extraction with industrial applications.

A Novel Mesoporous SBA‐15 Supported Bifunctional Heterogeneous Catalyst for Base‐Free Transfer Hydrogenation Reaction of Ketones

ABSTRACTAmong the problems encountered in the catalytic transfer hydrogenation reactions of ketones, the base sensitivity of ketones and the corrosive effects of the bases used in the reaction have an important place especially in industrial terms. Although there are various approaches to overcome this problem, solutions based on the intrinsic properties of the catalyst used seem more suitable. Within the scope of this study, a novel heterogeneous catalyst was prepared for the transfer hydrogenation reaction of ketones, which can operate in base‐free environment. To prepare the heterogeneous catalyst, 1,2‐diphenylethane‐1,2‐diamine was first tosylated and then the silyl derivative was synthesized and grafted onto mesoporous silica SBA‐15. Characterizations of the obtained heterogeneous catalyst and SBA‐15 were carried out by X‐ray diffractometer (XRD), N2 sorption, thermogravimetric analysis (TGA), scanning electron microscope (SEM), energy dispersive X‐ray analysis, and Fourier transform infrared (FT‐IR) analysis. The results obtained showed that the functionalized 1,2‐diphenylethane‐1,2‐diamine compound was successfully immobilized into the SBA‐15 structure. Determination of the catalytic activity of the heterogeneous catalyst was carried out in transfer hydrogenation reactions of various aromatic ketones. After determining the optimum reaction conditions with acetophenone, a conversion rate of (70%) was observed in the acetophenone to 1‐phenylethanol reaction that took place without a base. Under same conditions a higher conversion rate of (73%) was observed in the 4′‐chloroacetophenone to 1‐(4‐chlorophenyl)ethanol reaction. In the reactions performed to determine recyclability, after a 70% conversion rate, 61% and 65% conversion rates, respectively, were observed in the reaction from acetophenone to 1‐phenylethanol under the same conditions.

A Programmable Oral Nanomotor Microcapsule for the Treatment of Inflammatory Bowel Disease

AbstractGiven the unique anatomy and location of inflammatory bowel disease (IBD), oral pharmacological treatment is the mainstay for managing IBD because of its convenience and direct accessibility to the gastrointestinal tract. However, efficient delivery systems must be designed to navigate the harsh gastrointestinal environment during application. Here, an innovative oral drug delivery system was proposed using nanomotor (NM)‐loaded soluble microcapsules for treating IBD. MnO2‐Au‐mSiO2 NMs incorporate partially encapsulated MnO2 antennas that convert reactive oxygen species into oxygen, autonomously propelling the NMs. Astaxanthin (AST), known for its anti‐inflammatory properties, is loaded into the mesoporous silica (mSiO2) of NMs (AST@NMs). AST effectively reduces inflammation and shifts macrophages from a proinflammatory (M1) phenotype to an anti‐inflammatory (M2) phenotype. To protect the nanomotors from harsh digestive conditions and achieve intestinal‐responsive release, using photocurable 3D printing, we fabricated enteric‐coated oral microcapsules (MCs). Additionally, to prevent leakage of AST@NMs, a calcium alginate shell was cured in situ on the surface of the microcapsules (AST@NMs@MCs). In vitro and in vivo, AST@NMs@MCs effectively reduced inflammation, repaired the intestinal barrier, and modulated the gut microbiota. These findings underscore the protective effects of the microcapsules on AST@NM, highlighting their potential as a promising strategy for treating colitis.

Supported phenylalanine on core-shell mesoporous microsphere as a catalyst for the synthesis of triazolo[1,2-a] indazole-triones and spiro triazolo[1,2-a] indazole-tetraones

In recent years, mesoporous silica materials have gained attention due to their unique properties, such as high surface area, pore volume, size, and chemical stability. These characteristics make them effective in various fields, particularly efficient supports in heterogeneous catalytic reactions. The present study developed a novel type of core-shell mesoporous microsphere material by anchoring phenylalanine on a core-shell SiO2@NiO@MS support. The catalyst support (SiO2@NiO@MS) was synthesized through homogeneous precipitation and sol-gel methods, with NiO encapsulated within the porous silica. The catalyst was characterized using various techniques, including Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive spectroscopy (EDS), Elemental mapping analysis, N2 adsorption-desorption, Transmission electron microscopy (TEM), Vibrating sample magnetometer (VSM), and Thermogravimetric analysis (TGA). It was then employed for the synthesis of triazolo[1,2-a]indazole-trione and spiro triazolo[1,2-a]indazole-tetraones compounds from 4-phenyl urazole, dimedone, and aromatic aldehydes or isatin derivatives. This synthetic approach offers multiple advantages, including high yields, faster reaction times, low catalyst requirements, and environmentally sustainable conditions.

Synthesis and Characterization of Mesoporous Materials Functionalized with Phosphinic Acid Ligand and Their Capability to Remove Cd(II)

This article presents a study of cadmium removal from nitrate medium using adsorption in calcined mesoporous silica (MCM-C), mesoporous silica doped (MCM_DIOPA), and calcined and impregnated mesoporous silica (MCM@DIOPA), with diisooctylphosphinic acid (DIOPA). The sorbents were synthesized via a sol–gel method. Several characterization techniques, such as XRD, FTIR spectroscopy, N2 sorption and elemental analysis, have been used to determine the main structural, textural, and chemical properties of prepared sorbents. Batch adsorption and kinetics tests were carried out, where the influence of pH and contact time of the sorbents and their role in cation removal were studied. Experimental results show poor sorption efficiencies with MCM-C and MCM_DIOPA at pH 5.85. At the same pH, better cadmium extraction was attained by MCM@DIOPA and was achieved within 30 min. The pseudo-second-order model is the most appropriate model to describe the elimination mechanism of Cd(II) ions. The Langmuir equation was used to model the sorption isotherm and the maximum sorption capacity of Cd(II) is 22.16 mg/g (200 mmol/kg). The complex type of the probable extracted species isCdL2-HL.

Enhanced catalytic performance of ethyl-levulinate to γ-valerolactone: Effect of copper loading on Ni/KIT-5 catalyst

A facile wet impregnation method was employed to prepare a bimetallic Ni–Cu catalyst on a mesoporous KIT-5 support, keeping the nickel loading constant (5 wt%) while varying the copper wt.% (xCu, where x = 8, 10, 12, 14). Several physico-chemical techniques, including X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), temperature-programmed desorption of ammonia (NH3-TPD), temperature-programmed reduction of hydrogen (H2-TPR), and X-ray photoelectron spectroscopy (XPS), were utilized for catalyst characterization. An environmentally friendly NiCu bimetallic-supported catalyst system was developed in response to many problems, including metal leaching, sintering, and cost. A mesoporous KIT-5 silica support with a large surface area was used. The hydrogenation of ethyl levulinate to gamma-valerolactone was studied utilizing a high-pressure stirred reactor and a range of reaction temperatures (120–160 °C), hydrogen pressures (10–30 bar), and reaction periods. Various catalysts were used in the investigation. Among all tested catalysts, the 12Cu–5Ni/KIT-5 one shows excellent activity. The best GVL yield is 84% at a conversion of 100% after 8 h of treatment at 150 °C and 25 bar H2 pressure; the promotion is also 76.1%. Optimization of reaction conditions was shown to correlate the physicochemical parameters of the catalyst with its activity.

Multifunctional and novelty green composite film containing sodium alginate, chitosan, rice husk and curcumin.

Foodborne diseases are a global public health issue, with their causes often originating from lapses in food production or transportation leading to food contamination. Therefore, food packaging plays a crucial role in preserving the safety and quality of food. In pursuit of sustainable development, this study aims to utilize agricultural waste-derived functional mesoporous silica nanoparticles in combination with biodegradable molecules to create food packaging films. Through recycling and the use of environmentally friendly green films, the goal is to achieve sustainability and the objectives of green chemistry. The study anticipates the production of biodegradable films and the testing of their antibacterial capabilities, antioxidant properties, biocompatibility, and film stress coefficients. This research will provide robust support for advancing green packaging technology to address the challenges of global food safety and environmental sustainability. The experiment is divided into two parts. The first part involves the synthesis of multifunctional mesoporous silica nanoparticles with antibacterial properties derived from rice husk (Rice husk mesoporous silica nanoparticles, rMSN) as nano-fillers. These nanoparticles are surface modified with a biodegradable polymer, chitosan (Chi), that interacts with the material. Natural extract curcumin (Cur), known for its antioxidant capabilities, is loaded into the pores, and the material's inherent antibacterial properties are utilized. The second part involves blending the material with the natural polymer sodium alginate (SA) to form a film (rMSN-Chi@Cur/Alg film). The film's thickness, stress strength, antibacterial, and antioxidant capabilities are tested to ensure the material possesses antibacterial and antioxidant properties.

A bone-targeting delivery platform based on mesoporous silica loaded with piR7472 for the treatment of osteoporosis

A bone-targeting delivery platform based on mesoporous silica loaded with piR7472 for the treatment of osteoporosis

Thrombin Immobilized on Magnetic Core-Shell Mesoporous Silica Nanoparticles for Screening of the Enzyme Inhibitors From Notopterygium Incisum.

Thrombin was immobilized on magnetic core-shell mesoporous silica nanoparticles (Fe3O4@nSiO2@mSiO2) for the first time and used to screen enzyme inhibitors from extracts of Notopterygium incisum. The immobilized thrombin was characterized by Fourier-transform infrared spectroscopy, transmission electronic microscopy, thermal gravimetric analysis, and vibrating sample magnetometry. The results demonstrated that the immobilized thrombin possessed good thermal stability and high-temperature resistance for feasible storage and reuse. Two ligands, notopterol (1) and isoimperatorin (2) were fished out from the extract of N. incisum using the immobilized thrombin. They inhibited thrombin with IC50 values of 59.35±1.420 and 107.8±1.660µM, respectively. This is the first report of thrombin-inhibitory activity associated with notopterol and isoimperatorin. Meanwhile, the inhibition mechanism of both compounds was investigated by enzyme kinetic analysis and molecular docking. The method used enables rapid screening for thrombin inhibitors from medicinal plants, providing an efficient tool for the discovery of anti-thrombotic active compounds.

Synthesis of cubic mesoporous silica SBA16 functionalized with carboxylic acid in a one-pot process for efficient removal of wastewater containing Cu2+: Adsorption Isotherms, Kinetics, and Thermodynamics

Synthesis of cubic mesoporous silica SBA16 functionalized with carboxylic acid in a one-pot process for efficient removal of wastewater containing Cu2+: Adsorption Isotherms, Kinetics, and Thermodynamics

Dual photosensitizers material for photodynamic theraphy

Abstract Fluoride-based upconversion luminescent materials have the advantage of low phonon energy, which can effectively reduce the non-radiative transition process, so that materials have higher luminous efficiency than other matrix materials. The core–shell NaGdF4:Er3+, Yb3+ @NaGdF4:Tm3+, Yb3+ nanoparticals were synthesized by thermal decomposition method. The core–shell structure can effectively avoid the surface quenching effect, meanwhile, Tm3+ in the shell transmits part of the photons in its excited state to Er3+, effectively enhancing the red emission of Er3+ and improving the luminous efficiency of the samples as a whole. The samples were further coated with a layer of mesoporous silica(mSiO2), where the photosensitizer(PS) Ce6 (red light activated) and MC540 (blue-green light activated) were compounded on through covalent bonds and electrostatic forces, respectively. So that three visable lights include red, green, and blue are all emitted from the sample to activate the PSs to produce reactive oxygen species (ROS) under 980 nm laser irradiation. In cells experiments, the samples were modified with folic acid (FA), which can mediated the cancer cells to target endocytosis. Notable photodynamic therapy (PDT) efficiency was observed under this dual-photosensitizers composite samples for its ROS generation.

Microstructure evolution of alite in-situ carbonated by aminated mesoporous silica nanoparticles

Microstructure evolution of alite in-situ carbonated by aminated mesoporous silica nanoparticles

Nanometer-Scale Tunable mesopores in silica fillers for Facile enhancement of epoxy adhesion

Epoxy resins are essential polymeric materials for various industrial applications owing to their excellent adhesion, thermal properties, and processability. Reported improvement methods for overcoming the limitations of epoxy-resin adhesives involve incorporating fillers such as silica, clay, carbon nanotubes, and graphene. While silica nanoparticles are commonly used in industrial applications, their properties often require enhancement. In this study, mesoporous silica nanoparticles (MSNs) were synthesized using cetyltrimethylammonium bromide and novel swelling agents, 2,6-dihydroxybenzoic acid and decane, to control pore sizes within the 2–4 nm range. Transmission electron microscope and nitrogen adsorption analyses confirmed pore sizes of 2.0, 3.1, and 3.9 nm. Applying MSNs as nanofillers to epoxy resin adhesive resulted in enhanced adhesive properties with increasing pore size, particularly with 0.5 wt% MSN-4 nm, achieving a 51.4 % improvement in shear strength compared to that of bare epoxy resin. This enhancement is attributed to the increased specific surface area of the MSNs, providing more interaction sites with the epoxy resin and improving resin penetration and interaction. These findings highlight the critical role of nanopore size in optimizing adhesion in nanofiller applications and emphasize the potential of MSNs as superior nanofillers for future industrial applications.

Inhibition of Polyphenol Oxidase Activity by Mesoporous Silica Nanoparticles and Multiwalled Carbon Nanotubes Modified with Surfactants.

Polyphenol oxidase (PPO) is the culprit behind the browning of fruits and vegetables. Therefore, how to reduce the thermal deactivation temperature of PPO or use as few safe reagents as possible to inhibit enzymatic browning has practical significance. Mesoporous silica nanoparticles (MSNs) and multiwalled carbon nanotubes (MWCNTs) are stable and have high biosafety. In the present study, efficient PPO inhibitors were developed based on MSNs and MWCNTs. It is found that after modification with a very small amount of dodecyl trimethylammonium bromide (DTAB, ≥60 μg/mL), MSNs can significantly inhibit the activity of PPO although single MSNs and single DTAB show very limited effect on PPO activity. After modification with a very small amount of sodium dodecyl sulfate (SDS, 5.7-9.5 μg/mL), MWCNTs almost completely inactivate PPO. However, SDS@MSN and DTAB@MWCNT cannot decrease PPO activity significantly.

Wormhole Mesoporous Silica Framework with Enhanced Thiol Loading for Improved Hg2+ Sequestration.

Thiol-functionalized mesoporous silica and materials potentially dedicated to diverse applications of composite materials, metal colloids, and metal catalysts, etc. Here, we developed a new synthesis route for 3-methacryloxypropyl trimethoxy silane (MPTMS) functionalized mesoporous silica (KIT-6), achieving a 71.5 % enhancement in thiol functionalization on KIT-6 surfaces. Characterization using XRD, TEM, BET, FTIR, Raman, 29Si NMR, XPS, and ICP-OES revealed structural and morphological features. XRD, TEM, and BET confirmed the three-dimensional structural stabilization of mesoporous silica with ~4 nm pore diameter and a surface area of 1451 m2 g-1. FTIR, Raman, and 29Si NMR studies established the mechanism of thiol functionalization, the formation of a new wormhole chain structural framework (WCSF), and stabilization through hydrogen bonding within the mesopores. The 29Si NMR spectra showed characteristic peaks (T3, T2, Q4, Q3) indicating self-condensed functionalized thiols with siloxane networks. XPS analysis validated enhanced thiol functionalization, indicating a structurally homogeneous WCSF suitable for mercury adsorption. ICP-OES measured a mercury adsorption capacity of 3199.6 mg g-1 for KIT-6, with an Hg2+/S ratio of 1.8, corroborated by molecular structure and mechanism analysis. This innovative thiol functionalization approach enhances the efficacy of applications such as extracting Hg2+ from contaminated sources.

Doxorubicin- and Selenium-Incorporated Mesoporous Silica Nanoparticles as a Combination Therapy for Osteosarcoma

Doxorubicin- and Selenium-Incorporated Mesoporous Silica Nanoparticles as a Combination Therapy for Osteosarcoma

TLR Agonist Nano Immune Therapy Clears Peritoneal and Systemic Ovarian Cancer.

Intraperitoneal (IP) administration of immunogenic mesoporous silica nanoparticles (iMSN) in a mouse model of metastatic ovarian cancer promotes the development of tumor-specific CD8+ T cells and protective immunity. IP delivery of iMSN functionalized with the Toll-like receptor (TLR) agonists polyethyleneimine (PEI), CpG oligonucleotide, and monophosphoryl lipid A (MPLA) stimulated rapid uptake by all peritoneal myeloid subsets. Myeloid cells quickly transported iMSN to milky spots and fat-associated lymphoid clusters (FALCs) present in tumor-burdened adipose tissues, leading to a reduction in suppressive T cells and an increase in activated memory T cells. Two doses of iMSN cleared or reduced ovarian and colorectal cancer and protected against future tumor engraftment. In contrast, subcutaneous (SC) and intravenous (IV) delivery of iMSN were without therapeutic effect in mice with peritoneal metastases, supporting the need for activation of regional immune cells. Remarkably, intraperitoneal delivery of iMSN cleared subcutaneously implanted ovarian cancer, supporting homing of antigen specific T cells to extraperitoneal tumor sites.

Preparation of Novel Hierarchical Catalysts by Simultaneous Generation of β-Zeolite and Mesoporous Silica for Catalytic Cracking.

The gel skeletal reinforcement (GSR) method was applied at the preparation stage of β-zeolite to prepare a novel hierarchical catalyst. A solution of hexamethyldisiloxane (HMDS) and acetic anhydride, a GSR reagent, was added to the mixture of colloidal silica, sodium aluminate, tetraethylammonium hydroxide, sodium hydroxide and water, and successive aging and hydrothermal treatment gave microporous β-zeolite surrounded by mesoporous silica like core-shell structure. Its properties were characterized by XRD, nitrogen adsorption and desorption, NH3-TPD, TEM, and TG-DTA measurements, and further characteristics of the catalysts produced were clarified by the catalytic cracking of n-dodecane. The hierarchical structure of microporous zeolite and mesoporous silica was shown from GSR-2.9HS-H-Beta to GSR-3.2HS-H-Beta, where the molar ratio of HMDS and silica source of β-zeolite was 2.9~3.2 : 100. It was found that in the catalytic cracking of n-dodecane, the relative activity (the conversion per the amount of zeolite crystals) increased with the increase in mesopore volume and surface area. The result indicated that the introduction of mesopores was effective even in catalytic cracking of small molecule of n-dodecane.

Reimagining Anti-Inflammatory Drugs Delivery: The Integration of Ordered Mesoporous Silica and MOF Materials for Enhanced Therapeutic Outcomes

Abstract Migraine, one of the neurological conditions, affects approximately 15% of the global population. It is characterized by intense headaches accompanied by nausea, vomiting, and heightened sensitivity to light. The first line of drugs for treating migraine are non-steroidal anti-inflammatory drugs. Unfortunately, these medications suffer from poor solubility in water, uncontrolled release, and numerous adverse side effects. In order to maximize their therapeutic effect by preventing premature release and degradation, novel drug delivery systems based on composites are being dynamically developed. Herein, the biocompatible ketoprofen, naproxen sodium, and diclofenac sodium vehicles integrating ordered mesoporous silica (SBA-16) with Fe-based metal–organic frameworks (MIL-101(Fe)) were synthesized via the solvothermal method. The composites were characterized by different percentages of MIL-101(Fe) 
(25 and 50 wt.%), which had a significant impact on their porosity, structure, and number of functional groups. The SBA-16@MIL-101(Fe)-25 and SBA-16@MIL-101(Fe)-50 samples exhibited BET surface areas of 768 and 324 m2/g, respectively. Their sorption capacities towards selected anti-inflammatory drugs were in the range of 141-318 mg/g for ketoprofen, 481-490 mg/g for naproxen sodium, and 246-589 mg/g for diclofenac sodium, notably exceeding the values obtained for pure mesoporous silica (5-9 mg/g). Morphological defects and specific functional groups, derived from SBA-16 and MIL-101(Fe), contributed to generating new adsorption sites in composites, enhancing host-guest interactions. The drug release profiles were determined by the carrier porosity, surface charge, and the presence of functional groups. The diffusion of ketoprofen and diclofenac sodium from the composites into the phosphate buffer (pH 7.7), mimicking rectal fluid, occurred in a more controlled manner compared to pristine silica. The SBA-16@MIL-101(Fe)-50 carrier released 82% of ketoprofen and 90% of diclofenac sodium over 24 hours.