Mesoporous Silica Nanocapsules Research Articles

Amplified Sensitivity in SERS Detection of L1CAM With Silver Plasmonic Mesoporous Silica Capsules on an Imprinted Films

AbstractThis study presents a novel approach for dual detection, leveraging a combination of a Raman reporter‐bearing nanomaterial and molecular imprinting polymers (MIP). A core‐shell Au‐Ag nanoparticles (Au‐Ag NPs) encapsulated in mesoporous silica nanocapsules (Au‐Ag NCs) and a new MIP‐based material targeting L1CAM are used. The MIP prepared via surface imprinting on a carbon screen‐printed electrode (C‐SPE) used thionine (TH) as a monomer. The plasmonic Au‐AgNCs are further functionalized with the Raman reporter 4‐mercaptobenzoic acid (MBA) and anti‐L1CAM for selective detection by surface‐enhanced Raman scattering (SERS) spectroscopy. The biosensor's analytical performance is evaluated using both SERS and electrochemical impedance spectroscopy (EIS). EIS analysis reveals a linear response within the concentration range of 0.1 to 100 ng mL−1 in buffer and serum samples. SERS demonstrates a sensitivity ten times higher than EIS. Selectivity study demonstrates the biosensor's excellent specificity toward L1CAM, with minimal interference from other compounds such as creatinine, glucose, and carbohydrate antigen 19‐9 (CA 19‐9). The Raman signal from the reporter molecule correlates with increasing L1CAM concentrations, reinforcing the analytical findings obtained through electrochemical analysis. Thus, the combination of dual detection and recognition capabilities presents promising potential for detecting diverse biomarkers, especially in critical scenarios where reducing false‐positive or false‐negative errors is crucial.

Tribological properties of a smart Ti3C2Tx-based epoxy coating: Providing an idea to solve the weak tribological properties of traditional smart coatings

Friction damage is always a major threat to the wide application of smart anticorrosion coatings. Here, the tribological properties of a smart Ti3C2Tx-based epoxy coating (MLT@EP) is adjusted by the reasonable collocation of mesoporous silica nanocapsules loading onto Ti3C2Tx-based plane (MLT). MLT@EP not only maintains good smart anticorrosion, but also has remarkable anti-friction and anti-wear properties. Its friction coefficient exhibits a low and steady trend, and the wear rate arrived at 1.14 × 10−5 mm3/N·m, which is decreased by 58.3 ∼ 93.3 % compared to control groups. The excellent tribological properties are mainly attributed to the synergistic effect of MXene-based lubrication film, high resistance to plastic deformation, and strong internal interaction.

Ivermectin-Loaded Mesoporous Silica and Polymeric Nanocapsules: Impact on Drug Loading, In Vitro Solubility Enhancement, and Release Performance.

Ivermectin (IVM), a widely used drug for parasitic infections, faces formulation and application challenges due to its poor water solubility and limited bioavailability. Pondering the impact of IVM's high partition coefficient value (log P) on its drug release performance, it is relevant to explore whether IVM nanoencapsulation in organic or inorganic nanoparticles would afford comparable enhanced aqueous solubility. To date, the use of inorganic nanoparticles remains an unexplored approach for delivering IVM. Therefore, here we loaded IVM in mesoporous silica particles (IVM-MCM), as inorganic nanomaterial, and in well-known poly(ε-caprolactone) nanocapsules (IVM-NC). IVM-MCM had a well-organized hexagonal mesoporous structure, reduced surface area, and high drug loading of 10% w/w. IVM-NC had a nanometric mean size (196 nm), high encapsulation efficiency (100%), physicochemical stability as an aqueous dispersion, and drug loading of 0.1% w/w. Despite differing characteristics, both nanoencapsulated forms enhance IVM's aqueous intrinsic solubility compared to a crystalline IVM: after 72 h, IVM-MCM and IVM-NC achieve 72% and 78% releases through a dialysis bag, whereas crystalline IVM dispersion achieves only 40% drug diffusion. These results show distinct controlled release profiles, where IVM-NC provides a deeper sustained controlled release over the whole experiment compared to the inorganic nanomaterial (IVM-MCM). Discussing differences, including drug loading and release kinetics, is crucial for optimizing IVM's therapeutic performance. The study design, combined with administration route plans and safety considerations for humans and animals, may expedite the rational optimization of IVM nanoformulations for swift clinical translation.

Adults of Sun Coral Tubastraea coccinea (Lesson 1829) Are Resistant to New Antifouling Biocides.

Biocides used in antifouling (AF) paints, such as 4,5-dichlorine-2-n-octyl-4-isothiazole-3-one (DCOIT), can gradually leach into the environment. Some AF compounds can persist in the marine environment and cause harmful effects to non-target organisms. Nanoengineered materials, such as mesoporous silica nanocapsules (SiNCs) containing AF compounds, have been developed to control their release rate and reduce their toxicity to aquatic organisms. This study aimed to evaluate the acute toxicity of new nanoengineered materials, SiNC-DCOIT and a silver-coated form (SiNC-DCOIT-Ag), as well as the free form of DCOIT and empty nanocapsules (SiNCs), on the sun coral Tubastraea coccinea. T. coccinea is an invasive species and can be an alternative test organism for evaluating the risks to native species, as most native corals are currently threatened. The colonies were collected from the Alcatrazes Archipelago, SP, Brazil, and acclimatized to laboratory conditions. They were exposed for 96 h to different concentrations of the tested substances: 3.33, 10, 33, and 100 µg L-1 of free DCOIT; 500, 1000, 2000, and 4000 µg L-1 of SiNC; and 74.1, 222.2, 666.7, and 2000 µg L-1 of SiNC-DCOIT and SiNC-DCOIT-Ag. The test chambers consisted of 500 mL flasks containing the test solutions, and the tests were maintained under constant aeration, a constant temperature of 23 ± 2 °C, and photoperiod of 12 h:12 h (light/dark). At the end of the experiments, no lethal effect was observed; however, some sublethal effects were noticeable, such as the exposure of the skeleton in most of the concentrations and replicates, except for the controls, and embrittlement at higher concentrations. Adults of T. coccinea were considered slightly sensitive to the tested substances. This resistance may indicate a greater capacity for proliferation in the species, which is favored in substrates containing antifouling paints, to the detriment of the native species.

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.

Marine Hazard Assessment of Soluble and Nanostructured Forms of the Booster Biocide DCOIT in Tropical Waters

The encapsulation of antifouling compounds, such as DCOIT (4,5-Dichloro-2-octylisothiazol-3(2H)-one), in mesoporous silica nanocapsules (SiNC) has recently been demonstrated to be an eco-friendly alternative to decrease biocide toxicity towards marine non-target species. However, the lack of information on the chronic effects of such nanomaterials on non-target tropical species is critical for a more comprehensive environmental risk assessment. Thus, the present study aimed to assess the chronic toxicity and hazard of the soluble and encapsulated forms of DCOIT on neotropical marine species. Chronic tests were conducted with six ecologically relevant species. No effect concentration (NOEC) values were combined with NOEC values reported for tropical species to assess the hazard using the probabilistic approach to derive each predicted no effect concentration (PNEC). The SiNC-DCOIT was three- to ten-fold less toxic than soluble DCOIT. Probabilistic-based PNECs were set at 0.0001 and 0.0097 µg DCOIT L−1 for the biocide soluble and nanostructured forms, respectively. The immobilization of DCOIT into SiNC led to an 84-fold hazard decrease, confirming that the encapsulation of DCOIT into SiNC is a promising eco-friendly alternative technique, even in a chronic exposure scenario. Therefore, the present study will contribute to better management of the environmental risk of such innovative products in the tropical marine environment.

Can Encapsulation of the Biocide DCOIT Affect the Anti-Fouling Efficacy and Toxicity on Tropical Bivalves?

The encapsulation of the biocide DCOIT in mesoporous silica nanocapsules (SiNC) has been applied to reduce the leaching rate and the associated environmental impacts of coatings containing this biocide. This research aimed to evaluate the effects of DCOIT in both free and nanostructured forms (DCOIT vs. SiNC-DCOIT, respectively) and the unloaded SiNC on different life stages of the bivalve Perna perna: (a) gametes (fertilization success), (b) embryos (larval development), and (c) juveniles mussels (byssus threads production and air survival after 72 h of aqueous exposure). The effects on fertilization success showed high toxicity of DCOIT (40 min-EC50 = 0.063 μg L−1), followed by SiNC-DCOIT (8.6 μg L−1) and SiNC (161 μg L−1). The estimated 48 h-EC50 of SiNC, DCOIT and SiNC-DCOIT on larval development were 39.8, 12.4 and 6.8 μg L−1, respectively. The estimated 72 h-EC50 for byssus thread production were 96.1 and 305.5 µg L−1, for free DCOIT and SiNC-DCOIT, respectively. Air survival was significantly reduced only for mussels exposed to free DCOIT. Compared to its free form, SiNC-DCOIT presented a balanced alternative between efficacy and toxicity, inhibiting efficiently the development of the target stage (larvae that is prone to settle) and satisfactorily preventing the juvenile attachment.

Preparation of mesoporous silica nanocapsules with a high specific surface area by hard and soft dual templating approach: Application to biomass valorization catalysis

Abstract Mesoporous silica nanocapsules were prepared by a soft and hard dual templating approach. Carbon black and carbon nanofibers, used as sacrificial templates (hard template) have been coated by a mesoporous silica layer. Pluronics (P123/F127) and cetrimonium bromide were selected as surfactants (soft template) to produce mesoporous layers with different morphologies and pore sizes. The coated samples were then calcined at high temperature to remove the hard template and produce silica nanocapsules with mesopores in their walls. The so-obtained materials have been characterized by XPS, elemental analyses (ICP), TEM, N2 physisorption and XRD. The results have shown that the obtained materials exhibit a high specific surface area and a short diffusional pathway within the porous structure, which represents a significant advantage for catalysis applications. Finally, mesoporous acidic nanocapsules were prepared by sulfonic acid moieties grafting, and were tested as a catalyst in a biomass valorization reaction, the hydrolysis of cellobiose. The catalysts have shown high catalytic performances underlining the high potential of the present synthetic approach to produce versatile mesoporous materials.

Thioether-bridged mesoporous organosilica nanocapsules with weak acid-triggered charge reversal for drug delivery

The drug delivery nanosystems with weak acid-triggered surface charge reversal function should be promising for efficient chemotherapy due to the prolonged blood circulation and enhanced the cellular uptake. However, there are only limited reports up to now. In this study, we fabricated a hybrid nanocapsule with a negative-to-positive charge-reversal outer layer triggered by the weak acidity in tumor microenvironment. The short branched polyethylenimine (PEI) with positive charge and weak acid-sensitive hexahydrophthalic anhydride with negative charge were successively modified on the surface of small uniform thioether-bridged hollow mesoporous silica nanospheres with multiple cavities. The modification of PEI as a linker was more favorable for charge reversal than that of aminopropyl group. The constructed hybrid nanocapsules exhibited weak acid (pH 6.0)-triggered charge reversal and drug release behaviors, thus effectively inhibiting the growth of A549 cancer cells. The surface functionalization of hybrid nanocapsules opens new opportunities for the development of silica-based hybrid nanosystems for promising drug delivery. Thioether-bridged hollow mesoporous silica nanocapsules with weak acid-triggered charge reverse and drug release are designed and constructed for efficient tumor drug delivery. • Branched PEI and hexahydrophthalic anhydride were modified on thioether-bridged mesoporous organosilica nanocapsules. • The constructed hybrid nanocapsules exhibited weak acid (pH 6.0)-triggered charged reversal and DOX release behaviors.

Correction to Regulation of Ca2+ Signaling for Drug-Resistant Breast Cancer Therapy with Mesoporous Silica Nanocapsule Encapsulated Doxorubicin/siRNA Cocktail.

Multidrug resistance (MDR) is the key cause that accounts for the failure of clinical cancer chemotherapy. To address the problem, herein, we presented an alternative strategy to conquer drug-resistant breast cancer through the combinatorial delivery of Ca2+ channel siRNA with cytotoxic drugs. Mesoporous silica nanocapsules (MSNCs) with mesoporous and hollow structure were fabricated for co-delivery of T-type Ca2+ channel siRNA and doxorubicin (DOX) with high drug loading efficiency. The DOX/siRNA co-loaded MSNCs showed a synergistic therapeutic effect on drug-resistant breast cancer cells MCF-7/ADR, while had only an additive effect on the drug-sensitive MCF-7 counterpart. It was found that the combination of T-type Ca2+ channel siRNA and DOX had a similar effect on MCF-7 and MCF-7/ADR in the knockdown of overexpressed T-type Ca2+ channels and decrease in cytosolic Ca2+ concentration ([Ca2+]i), but it specifically induced G0/G1 phase cell-cycle arrest and intracellular drug accumulation enhancement in MC...

Nanosensors for Monitoring Early Stages of Metallic Corrosion

A new generation of nanosensors based on mesoporous silica nanocapsules with the ability to monitor the onset of metallic corrosion is successfully developed and tested on 304 stainless steel. The core of the nanocapsules contains water insoluble organic molecules that fluoresce during the anodic dissolution of metallic substrates in the corrosion process. The dispersion of the nanosensors in organic coatings applied on metal substrate allows a very sensitive fluorescent detection of the initiation of metal dissolution, close to defects in the substrate. This promising concept offers therefore new perspectives for the development of smart coatings for corrosion sensing.

Regulation of Ca2+ Signaling for Drug-Resistant Breast Cancer Therapy with Mesoporous Silica Nanocapsule Encapsulated Doxorubicin/siRNA Cocktail.

Multidrug resistance (MDR) is the key cause that accounts for the failure of clinical cancer chemotherapy. To address the problem, herein, we presented an alternative strategy to conquer drug-resistant breast cancer through the combinatorial delivery of Ca2+ channel siRNA with cytotoxic drugs. Mesoporous silica nanocapsules (MSNCs) with mesoporous and hollow structure were fabricated for co-delivery of T-type Ca2+ channel siRNA and doxorubicin (DOX) with high drug loading efficiency. The DOX/siRNA co-loaded MSNCs showed a synergistic therapeutic effect on drug-resistant breast cancer cells MCF-7/ADR, while had only an additive effect on the drug-sensitive MCF-7 counterpart. It was found that the combination of T-type Ca2+ channel siRNA and DOX had a similar effect on MCF-7 and MCF-7/ADR in the knockdown of overexpressed T-type Ca2+ channels and decrease in cytosolic Ca2+ concentration ([Ca2+]i), but it specifically induced G0/G1 phase cell-cycle arrest and intracellular drug accumulation enhancement in MCF-7/ADR. The in vitro and in vivo results demonstrated that the MSNCs with good biocompatibility had a high efficiency for conquering the drug-resistant breast cancer with the DOX/calcium channel siRNA cocktail co-delivery. It provides a biological target for drug/gene delivery enhanced cancer therapy with nanoformulations.

Immobilization of Pt nanoparticles in hollow mesoporous silica nanocapsules: An aggregation- and leaching-resistant catalyst

In this study, hollow mesoporous silica nanocapsules (h-mNSiO2) with uniformly dispersed Pt nanoparticles (Pt NPs) in their hollow core (Pt@h-mNSiO2) were successfully fabricated. The as-synthesized Pt@h-mNSiO2 was core@shell like structure with silica shells and Pt-rich cores. The catalyst was synthesised in an oil-water biphasic stratification system, then the self-assembly of reactants occurred in the oil-water interface for one-pot sustaining interfacial growth. The as-prepared Pt@h-mNSiO2 catalyst exhibited superior activity for hydrogen generation from the hydrolysis of ammonia borane, with a turnover frequency of 371.7 molH2 mol−1Pt min−1 at ambient temperature, probably owing to the abundant mesopores and high surface area, leading to a considerable increase in the accessible active sites. Besides, almost no Pt NP aggregation was observed during reusability tests. Notably, Pt leaching was not observed during the reaction, possibly related to the protective effect of the mesoporous silica shell. Thus, this study provides a facile route to synthesise aggregation- and leaching-resistant catalysts with superior activity, accessibility, and recyclability for the environment and energy chemistry.

Antimacrofouling Efficacy of Innovative Inorganic Nanomaterials Loaded with Booster Biocides

The application of nano-structured compounds has been increasing rapidly in recent years, in several fields. The use of engineered nano-materials as carriers of antifouling compounds is just beginning and already reveals clear advantages compared to bulk active compounds, such as slowed and controlled release, novel functionality, and high loading capacity. This present study assesses the antifouling efficacy of two nanostructured materials, spherical mesoporous silica nanocapsules (SiNC) and Zn-Al layered double hydroxides (LDH), loaded with two commercial biocides, zinc prithione (ZnPT) and copper pyrithione (CuPT). The study used adult mussels from three geographical regions, the Atlantic Ocean, Mediterranean Sea, and the Red Sea, to examine the efficacy of the innovative compounds. The efficacy of these compounds on larvae of the bryozoan Bugula neritina from the Mediterranean Sea and the Red Sea was also examined. The results of this study demonstrated the environmentally friendly properties of unloaded LDH against the two-model systems, adult mussels or bryozoan larvae. ZnPT entrapped in LDH demonstrated the most effective antifouling compound against the two model systems. A comparison of the impact of the two compounds on macrofouling organisms from the different marine habitats examined in this study indicates a distinction associated with the organisms’ different ecosystems. The Red Sea mussels and bryozoans, representing a tropical marine ecosystem, yielded the highest efficacy values among tested Atlantic Ocean and Mediterranean Sea mussels and bryozoans.

An RGD-modified hollow silica@Au core/shell nanoplatform for tumor combination therapy.

We demonstrate a convenient approach to preparing a novel RGD-targeted drug delivery system of HMSs@Au-PEG-RGD NSs/DOX that possesses pH/NIR laser dual-responsive drug delivery performance for combinational chemotherapy and PTT of tumors. The developed Au NS-coated HMS capsules have both merits of HMS capsules that can be used for high payload drug loading and Au NSs that have NIR laser-induced photothermal conversion efficiency (70.8%) and can be used for PTT of tumors.

The pro-active payload strategy significantly increases selective release from mesoporous nanocapsules

The controlled release of payloads from mesoporous silica nanocapsules (SiNCs) consisting of stimulus-responsive shells is of considerable interest in applications such as self-healing materials and drug delivery. However, the release of payloads from SiNCs before application of external triggers (i.e. non-selective release) remains a formidable challenge. In fact, the non-selective release of payloads from SiNCs occurs because of the mesoporous nature of the silica shell that cannot trap payloads in the core of SiNCs perfectly. We establish an efficient and straightforward strategy based on the encapsulation of a pro-active payload to hinder the non-selective release of small payloads from mesoporous capsules. A pro-active payload is defined as a compound that is converted to an active functional molecule in the environment where it is needed. In this sense, it is a generalization of a prodrug. Encapsulating a pro-active payload instead of a payload allowed hindering the non-selective release of the payload from SiNCs. A selective release of the payload could be achieved upon reduction of the encapsulated pro-active payload. Furthermore, the total amount of released substance is significantly enhanced by introducing responsive groups in the silica shell. These results show that the pro-active payload strategy combined with the use of stimulus-responsive materials can be successfully exploited to achieve selective release of cargo from mesoporous nanocapsules.

Self-assembly synthesis of hollow double silica @ mesoporous magnesium silicate magnetic hierarchical nanotubes with excellent performance for fast removal of cationic dyes

In this work, novel hollow double silica @ mesoporous magnesium silicate magnetic hierarchical nanotubes (MgSNTs) were successfully synthesized by using magnetic mesoporous silica nanocapsules (MSNCs) as morphology templates via a hydrothermal method for the first time. MgSNTs were characterized by transmission electron microscopy, Mapping, X-ray diffraction, Fourier transform infraed spetroscopy, N2 adorption-desorption, X-ray photoelectron spectroscopy and vibrating sample magnetometry. The synthesized MgSNTs with high specific surface area (588m2/g), average pore width (7.13nm) and pore volume (1.05cm3/g) had high removal efficiency for low concentration methylene blue (70mg/L, 299mg/g) and high adsorption capacities for high concentration rodamine B (300mg/L, 752mg/g). Besides, it could be easily recovered due with the help of γ-Fe2O3 in the inner chamber. Moreover, the adsorption capacity, the influence of pH, adsorption kinetics and adsorption mechanism were also carefully and comprehensively investigated. The results indicated that magnetic magnesium silicate nanotubes (MgSNTs) using mesoporous silica nanocapsules as the assisted templates were promsing adsorbents for water purification.

Synthesis and characterization of magnetic elongated hollow mesoporous silica nanocapsules with silver nanoparticles

In this study, magnetic elongated hollow mesoporous silica nanocapsules (MSNCs) with center-radial pore channels were successfully fabricated for the first time by using the surfactant-template synthesis approach.

Macrophage Cell Membrane Camouflaged Mesoporous Silica Nanocapsules for In Vivo Cancer Therapy.

Engineering natural macrophage cell membrane-camouflaged mesoporous silica nanocapsules can reduce the arrested percentage of immune cells and tissues, effectively prolong the survival time of nanoparticles in blood circulation system, and improve the accumulation in tumor.

Synthesis of fragrance/silica nanocapsules through a sol–gel process in miniemulsions and their application as aromatic finishing agents

Mesoporous silica nanocapsules containing a series of fragrances were successfully prepared through an interfacial sol–gel process of tetraethoxysilane (TEOS) in miniemulsions. The hydrophobic liquid droplets of TEOS and fragrance worked as soft templates for forming a capsule morphology. The fragrance/silica nanocapsules were used to aromatically finish polymer films through drying a mixed emulsion of the fragrance/silica nanocapsules and polymer latex particles. The fragrance/silica nanocapsules were homogeneously distributed in the composite films. The release of fragrances from the composite film displayed a sustained manner. The introduction of the fragrance/silica nanocapsules could influence the thermal and mechanical properties of the composite films.