Dendritic Mesoporous Silica Nanoparticles Research Articles

Seeking Cells, Targeting Bacteria: A Cascade-Targeting Bacteria-Responsive Nanosystem for Combating Intracellular Bacterial Infections.

Intracellular bacteria pose a great challenge to antimicrobial therapy due to various physiological barriers at both cellular and bacterial levels, which impede drug penetration and intracellular targeting, thereby fostering antibiotic resistance and yielding suboptimal treatment outcomes. Herein, a cascade-target bacterial-responsive drug delivery nanosystem, MM@SPE NPs, comprising a macrophage membrane (MM) shell and a core of SPE NPs. SPE NPs consist of phenylboronic acid-grafted dendritic mesoporous silica nanoparticles (SP NPs) encapsulated with epigallocatechin-3-gallate (EGCG), a non-antibiotic antibacterial component, via pH-sensitive boronic ester bonds are introduced. Upon administration, MM@SPE NPs actively home in on infected macrophages due to the homologous targeting properties of the MM shell, which is subsequently disrupted during cellular endocytosis. Within the cellular environment, SPE NPs expose and spontaneously accumulate around intracellular bacteria through their bacteria-targeting phenylboronic acid groups. The acidic bacterial microenvironment further triggers the breakage of boronic ester bonds between SP NPs and EGCG, allowing the bacterial-responsive release of EGCG for localized intracellular antibacterial effects. The efficacy of MM@SPE NPs in precisely eliminating intracellular bacteria is validated in two rat models of intracellular bacterial infections. This cascade-targeting responsive system offers new solutions for treating intracellular bacterial infections while minimizing the risk of drug resistance.

Supramolecular self‐assembled nanoparticles for targeted therapy of myocardial infarction by enhancing cardiomyocyte mitophagy

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

Efficient self-healing coatings embedded with polydopamine modified BTA@DMSNs for corrosion protection

Dendritic mesoporous silica nanoparticles (DMSNs) were successfully prepared with a specific surface area of 608.8 m2/g and an average pore size of 24.2 nm, providing a strong support for the successful loading of benzotriazole (BTA). BTA@DMSNs were prepared using the vacuum impregnation method. A pH-responsive polydopamine (PDA) outer layer was self-polymerized on the surface to obtain BTA@DMSNs/PDA microcapsules. The pH-responsive BTA@DMSNs/PDA microcapsules were prepared with the high BTA content of 20.1 wt%. Mean diameter of microcapsules was 210 ± 25 nm. The release profiles under different pH conditions confirmed the pH-responsive behavior of BTA/DMSNs@PDA microcapsules. The coatings with 1 wt% BTA@DMSNs/PDA microcapsules exhibited optimal anti-corrosion and self-healing performance. The |Z|0.01Hz of EP/1 wt%/BTA/DMSNs@PDA remained the highest among all coatings even after being immersed in 3.5 wt% NaCl solution for 50 d through the EIS measurement. It only had a slight change from 3.8 × 1010 Ω·cm2 to 6.8 × 109 Ω·cm2, which was 80 times that of the EP for 50 d, indicating that the coatings had excellent long-term anti-corrosion effect and good shielding performance. Furthermore, the |Z|0.01Hz of the artificially cross-scratched coatings that were immersed for 30 d remained at 6.9 × 104 Ω·cm2, which was one order of magnitude higher than EP (6.3 × 103 Ω·cm2), and the surface of coatings remained intact, showing that the scratched coatings had outstanding self-healing performance.

Incorporation of dendritic silica nanoparticles for the preparation of high‐performance thin‐film nanocomposite membranes

AbstractThe development of thin‐film nanocomposite (TFN) membranes with high performance is conducive to efficient desalination and wastewater treatment. In this work, dendritic mesoporous silica nanoparticles (DLSiO2) were synthesized by a dual‐templating strategy. Afterward, they were introduced into the aqueous phase to fabricate TFN membranes via in situ interfacial polymerization (IP) reaction. Powerful techniques as scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, Nano zetasizer‐DLS, x‐ray photoelectron microscopy, electrokinetic analyzer, and contact angle were used in the characterization of dendritic structures and nanocomposite membranes. Results revealed that DLSiO2 with special structural characteristics can effectively regulate the IP process, promoting the enhancement of the crosslinking degree, surface hydrophilicity, and surface negative charge of polyaimde (PA) selective layers. It is also beneficial for constructing extra water channels within the PA selective layer to boost the transport of water molecules. As a consequence, the prepared TFN membrane with 0.3 mg/mL DLSiO2 exhibits optimal separation performance and good pressure resistance, acid–base resistance, and anti‐fouling properties. It also exhibited a water permeability of 4.17 L m−2 h−1 bar−1 (increased by 61.7% compared with thin film composites (TFC) membrane) and a NaCl rejection of 99.0%, which were better than those of TFN membranes prepared by introducing other types of silica in other studies.

Functional surface modifications impact on the in vitro/in vivo toxicity and intracellular internalization behavior of mesoporous silica nanoparticles

The surface properties of nanocarriers, including morphology, charge and surface modification are closely associated with their in vivo toxicity, biodistribution and bioavailability, which further affect the therapeutic effect. Herein, a series of in vitro and in vivo studies, including hemolysis, protein adsorption, cytotoxicity, cellular uptake and in vivo acute toxicity were performed to investigate the influences of surface properties on the biocompatibility and intracellular internalization behavior of functionalized degradable dendritic mesoporous silica nanoparticles (DDMSNs). The results illustrated that hyaluronic acid-modified DDMSNs (DDMSNs-NH2-HA) nanocarriers showed lower hemolysis, non-specific protein adsorption and in vitro cytotoxicity compared to DDMSNs and aminated DDMSNs (DDMSNs-NH2). The HA-mediated efficient intracellular internalization and significant accumulation of DDMSNs-NH2-HA in A549 cells was observed by cellular uptake assays. Furthermore, compared to DDMSNs and DDMSNs-NH2 groups, no significant pathological abnormalities were found in the hematoxylin and eosin-stained sections of key organs induced by DDMSNs-NH2-HA nanocarriers for in vivo toxicity, indicating that the improvement of nanocarriers’ biocompatibility arose from HA modification. This work explored the influencing mechanism of surface properties on biological toxicity and intracellular internalization behavior of nanocarriers in vitro and in vivo, which provided an insight into the design of biocompatible nano-DDS by rational surface modifications.

Controlled synthesis of sulfhydryl-dendritic mesoporous silica nanospheres for ultrafast extraction and sensitive analysis of organochlorine herbicides containing amide groups

The distinctive morphology of dendritic mesoporous silica nanoparticles (DMSN) has recently attracted considerable attention in scientific community. However, synthesis of DMSN with well-defined structure and uniform size for ultrafast extraction of trace herbicide residues from environmental and food samples remains to be a compelling challenge. In this study, sulfhydryl functionalized dendritic mesoporous silica (SH-DMSN) was synthesized and the SH-DMSN showcases monodisperse microspheres with flower shape and precisely tailored and controllable pore sizes. This distinctive structural configuration accelerates mass transfer within the silica layer, resulting in heightened adsorption efficiencies. Furthermore, the particle sizes (455, 765, and 808) of the adsorbent can be meticulously fine-tuned by introducing distinct templates. Specifically, when the particle size is 765 nm, the optimized SH-DMSN exhibits a substantial specific surface area (691.32 m²/g), outstanding adsorption efficiencies (>90 %), remarkably swift adsorption and desorption kinetics (2 min and 3 min, respectively), and exceptional stability. The superior adsorption capabilities of this novel adsorbent, ranging from 481.65 to 1021.7 µg/g for organochlorine herbicides containing amide groups, can be attributed to the interplay of S-π interactions, halogen bonding, and electrostatic attraction interaction. These interactions involve the lone pair electrons of sulfhydryl and silanol groups with the π-electrons, halogen atoms and amide groups in herbicide molecules. This study not only offers a new perspective on advancing the practical utilization of dendritic mesoporous silica but also provides a pragmatic strategy for the separation and analysis of herbicides in diverse sample matrices.

"One-Pot" Method Preparation of Dendritic Mesoporous Silica-Loaded Matrine Nanopesticide for Noninvasive Administration Control of Monochamus alternatus: The Vector Insect of Bursapherenchus xylophophilus.

Monochamus alternatus is an important stem-boring pest in forestry. However, the complex living environment of Monochamus alternatus creates a natural barrier to chemical control, resulting in a very limited control effect by traditional insecticidal pesticides. In this study, a stable pesticide dendritic mesoporous silica-loaded matrine nanopesticide (MAT@DMSNs) was designed by encapsulating the plant-derived pesticide matrine (MAT) in dendritic mesoporous silica nanoparticles (DMSNs). The results showed that MAT@DMSNs, sustainable nanobiopesticides with high drug loading capacity (80%) were successfully constructed. The release efficiency of DMSNs at alkaline pH was slightly higher than that at acidic pH, and the cumulative release rate of MAT was about 60% within 25 days. In addition, the study on the toxicity mechanism of MAT@DMSNs showed MAT@DMSNs were more effective than MAT and MAT (0.3% aqueous solutions) in touch and stomach toxicity, which might be closely related to their good dispersibility and permeability. Furthermore, MAT@DMSNs are also involved in water transport in trees, which can further transport the plant-derived insecticides to the target site and improve its insecticidal effect. Meanwhile, in addition, the use of essential oil bark penetrants in combination with MAT@DMSNs effectively avoids the physical damage to pines caused by traditional trunk injections and the development of new pests and diseases induced by the traditional trunk injection method, which provides a new idea for the application of biopesticides in the control of stem-boring pests in forestry.

Tailoring morphology for improved dispersibility of hydrophilic silica nanoparticles to fabricate thin-film nanocomposite membranes

Improving the dispersibility of nanomaterials is a promising approach to enhance the performance of thin-film nanocomposite (TFN) membranes. In this study, hydrophilic nonporous, mesoporous, and dendritic mesoporous silica nanoparticles (NSNs, MSNs, and DMSNs) with a uniform particle size were utilized as aqueous phase additives to prepare TFN membranes through in-situ polymerization. The electrostatic adsorption of nanoparticles increased the concentration of amine monomers on the surface of the polysulfone (PSF) substrate. In collaboration with the steric hindrance effect, nanoparticles restricted the diffusion of piperazine (PIP) into the organic phase to polymerize with the acyl chloride monomers. Compared to TFC-0, the TFN membranes exhibited a rougher surface with increased negative charge and had more channels that facilitated the transportation of water molecules. Among the nanoparticles, DMSNs exhibited excellent dispersibility, ensuring their uniform distribution within the polyamide (PA) matrix. Furthermore, DMSNs possessed an open central-radial pore structure, offering more efficient channels for water molecules to cross the membrane. Therefore, a highly crosslinked, defect-free, and hydrophilic PA layer of TFN-DMSNs was achieved. In the performance characterization, TFN-DMSNs demonstrated a high water/salt permselectivity (A/B) of up to 32.25 bar−1, and exhibited good resistance to acidic/alkaline environments as well as foulants during the operation. This study proposes a novel approach to prepare advanced TFN membranes by optimizing the morphological structure of nanoparticles.

Homogeneous fluorescence immunoassay based on AuNPs quenching dendritic silica assembled with multicolor QDs for the simultaneous determination of four mycotoxins in cereals

In this work, a novel homogeneous fluorescence immunoassay for the simultaneous detection of ochratoxin A (OTA), aflatoxin B1 (AFB1), fumonisins B1 (FB1), and zearalenone (ZEN) in cereal samples is established. Here, amino groups and thiol groups are grafted onto the surface of dendritic mesoporous silica nanoparticles (DMSNs) to improve loading rate and fluorescence preservation rate of quantum dots (QDs), enabling enrichment and amplification of fluorescence signals. In this test system, the fluorescence of the signal probe (DMSNs@QDs@Ab) is quenched by AuNPs, and then the presence of the targets makes the fluorescence of the signal probes recover. The correlation between the recovered fluorescence value and mycotoxin concentration is applied to achieve quantitative detecting mycotoxins. This assay displays good linear correlation in range of 0.01–100 μg L-1, with the limit of detection (LOD) of 0.0001 μg L-1 for OTA, 0.0008 μg L-1 for AFB1, 0.001 μg L-1 for FB1, and 0.0006 μg L-1 for ZEN, respectively. The proposed assay is applied to detect multiple mycotoxins in contaminated cereal samples and the test results is confirmed by liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Avail of silica with high loading capacity for assembling multicolor QDs to achieve simultaneous multi-signal output, a simple and efficient homogeneous fluorescence immunoassay is proposed for the first time. This multiplex test strategy provides a good idea for simultaneous, rapid, and sensitive detection of multiple hazardous substances in food and environment samples.

Monodisperse dendritic micro-mesoporous composite self-assembled with tiny TS-1 seeds as efficient catalysts for hydrodesulfurization of dibenzothiophenes

Novel TS-1/dendritic mesoporous silica nanoparticles (TS-1/DMSNs, TD) micro-mesoporous composites with different morphology were prepared for NiMo catalysts (NiMo/TD-TEA). Series catalysts were tested in dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) hydrodesulfurization (HDS) reactions in a fix-bed reactor. TS-1 were uniformly compounded with mesoporous materials in the form of Si-O-Ti bonds, which did not affect the typical dendritic morphology. The introduction of TEA could inhibit the growth of support particles, and modulate the acidity and the metal-support interaction (MSI) of catalysts. Optimized NiMo/TD-TEA catalyst showed the optimal DBT (98.0 %) and 4,6-DMDBT (92.3 %) desulfurization rate as well as the excellent hydrogenation (HYD) selectivity for DBT and 4,6-DMDBT HDS with the optimal reaction rate constant (12.2 mol·g−1·h−1, 6.7 mol·g−1·h−1) and turnover frequency (2.3 h−1, 1.4 h−1). By correlating to the catalyst acidity–activity and active phase–activity, the activity and selectivity were not only depended on the presence of Brønsted (B) acid and the total acid content but also associated with the dispersion and morphology of MoS2 slabs.

In Situ Synthesis of Highly Fluorescent, Phosphorus-Doping Carbon-Dot-Functionalized, Dendritic Silica Nanoparticles Applied for Multi-Component Lateral Flow Immunoassay.

The sensitivity of fluorescent lateral flow immunoassay (LFIA) test strips is compromised by the low fluorescence intensity of the signaling molecules. In this study, we synthesized novel phosphorus-doped carbon-dot-based dendritic mesoporous silica nanoparticles (DMSNs-BCDs) with a quantum yield as high as 93.7% to break this bottleneck. Meanwhile, the in situ growth method increased the loading capacity of carbon dots on dendritic mesoporous silica, effectively enhancing the fluorescence intensity of the composite nanospheres. Applied DMSNs-BCDs in LFIA can not only semi-quantitatively detect a single component in a short time frame (procalcitonin (PCT), within 15 min) but also detect the dual components with a low limit of detection (LOD) (carbohydrate antigen 199 (CA199) LOD: 1 U/mL; alpha-fetoprotein (AFP) LOD: 0.01 ng/mL). And the LOD of PCT detection (0.01 ng/mL) is lower by 1.7 orders of magnitude compared to conventional colloidal gold strips. For CA199, the LOD is reduced by a factor of four compared to LFIA using gold nanoparticles as substrates, and for AFP, the LOD is lowered by two orders of magnitude compared to colloidal gold LFIA. Furthermore, the coefficients of variation (CV) for intra-assay and inter-assay measurements are both less than 11%.

Magnetic dendritic mesoporous silica nanoparticles based integrated platform for rapid and efficient analysis of saccharides

BackgroundAs an essential compound in living organism, saccharides have attracted enormous attentions from scientists in various fields. Understanding the distribution of saccharides in various samples is of great scientific importance. However, the low signal response and lack of specific recognition technology of saccharides and the complex matrix of samples make the analysis of saccharides a very challenge task. Thus, the development of a simple and straightforward strategy for the analysis of saccharides would represent a great contribution to the field. ResultsIn this study, by employing the sulfonyl functionalized magnetic dendritic mesoporous silica nanoparticles as the substrate, we develop an integrated platform for analysis of saccharides. The construction of the platform mainly relied on multi-functional boronic acid, which serves as separation and derivation ligands at the same time. In the general procedure, the boronic acid is first immobilized onto the surface of substrate, then the selective enrichment of saccharides can be realized via boronate affinity separation. Finally, by the rational choice of the solution, we are able to elute the labelled complex (boronic acid-saccharide) from the substrate, which can be direct subjected to HPLC-UV analysis. The reliable precision (<15 %), accuracy (80–100 %), reproducibility (<10 %), improved sensitivity (20x) and limited time-consuming (down to minutes) of the proposed platform are experimentally demonstrated. Significance and noveltyThe successful quantification of different saccharides (alditols, glucose) in real samples is achieved. The proposed strategy is not only straightforward and fast, but also avoid the requirement of special equipment. With these attractive features, we believe that this strategy will greatly prompt the analysis of saccharides in various samples (eg. food, pharmaceutics and biosamples).

Synergistic reinforcement of immunogenic cell death and transformation of tumor-associated macrophages via an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform

The immune system's role in tumor growth and spread has led to the importance of activating immune function in tumor therapy. We present a strategy using an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform (M1mDDTF) to synergistically reinforce immunogenic cell death (ICD) and transform tumor-associated macrophages (TAMs) against tumors. The M1mDDTF nanoparticles consist of doxorubicin-loaded dendritic mesoporous silica nanoparticles chelated with FeIII-tannic acid (FeIIITA) and coated with M1-type macrophage membranes. In the acidic tumor microenvironment, FeIIITA releases Fe2+ and generates ·OH, aided by near infrared irradiation for enhanced doxorubicin release. Furthermore, the M1mDDTF nanoplatform not only directly kills tumor cells but stimulates ICD, which can increase the proportion of CD86+ CD80+ cells and promote dendritic cell maturation. Particularly, the M1mDDTF nanoplatform can also promote the gradual polarization of TAMs into the M1-type and promote tumor cell killing. This study demonstrates the safety and multifunctionality of M1mDDTF nanoparticles, highlighting their potential for clinical tumor treatment. Statement of significanceMalignant tumors are a global concern and a major cause of death. Nanoparticles' passive targeting is ineffective and hindered by reticuloendothelial system clearance. Therefore, enhancing nanoparticle accumulation in tumors while minimizing toxicity is a challenge. Coating nanoparticles with cell membranes enhances biocompatibility, immune evasion, and specific targeting. This approach has led to the development of numerous cell membrane-mimicking nanomaterials with remarkable properties and functions. This study developed an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform, boosting immunogenic cell death and transforming tumor-associated macrophages. Tannic acid in the tumor microenvironment reduced Fe3+ to Fe2+, generating ·OH. M1mDDTF nanosystem induced M1-type macrophage polarization, inhibiting tumor growth and triggering immune cell death. Safe and versatile, these M1mDDTF nanoparticles hold promise for clinical tumor treatment.

Co‐delivery of Curcumin and Doxorubicin Using a pH‐photothermal Dual‐responsive and CD44‐targeted Nanocarrier for Enhanced Chemo‐photothermal Synergistic Tumor Treatment

AbstractIn this study, we have developed a novel approach for synergistic tumor treatment by utilizing degradable dendritic mesoporous silica nanoparticles loaded with doxorubicin and curcumin (Cur). These nanoparticles are equipped with polydopamine (PDA) for photothermal therapy and hyaluronic acid (HA) as a targeting ligand. The incorporation of PDA not only ensures the controlled release of therapeutic agents but also confers pH and photothermal responsiveness to the nanocarriers. Cur, a natural compound, serves as an antitumor sensitizer, elevating intracellular ROS levels to promote apoptosis. In addition, the excellent biocompatibility and targeting property of nanocarriers were enhanced by the HA‐modification, improving the effective accumulation in tumor cells. Comprehensive research including MTT assay, live/dead staining and ROS generation proved that the excellent antitumor capability of dual‐drug loaded nanocarriers was a result of chemo‐photothermal synergistic therapy and Cur‐induced cellular amplified ROS generation. The cellular uptake assays further demonstrated the efficiency of HA‐mediated intracellular accumulation, accelerated uptake driven by photothermal‐induced and a precise internalization pathway of nanocarriers. Furthermore, the results of in vivo biocompatibility revealed no significant blood and organ toxicity associated to the prepared nanocarriers. Our findings underscore the substantial potential of the proposed dual‐drug loaded nanocarriers for chemo‐photothermal synergistic therapy, offering a safe and promising strategy for effective tumor treatment.

Facile Synthesis of Three Types of Mesoporous Silica Microspheres as Drug Delivery Carriers and their Sustained-Release Properties.

Mesoporous silica nanoparticles (MSNs) are one of the most promising carriers for drug delivery. MSNs have been widely used in pharmaceutical research as drug carriers because of their large pore volume, high surface area, excellent biocompatibility, nontoxicity, ease to functionalize, and sustained release effects. MSNs have attracted much attention during drug delivery because of their special structure. The present study aimed to synthesize mesoporous silica nanoparticles (MSNs), dendritic mesoporous silica nanoparticles (DMSN), and hollow mesoporous silica nanoparticles (HMSN) through facile methods, and to compare the drug release properties of nano-porous silica with different pore structures as a stroma for PUE drug. MSN, DMSN, and HMSN were characterized by SEM, TEM, FT-IR, nitrogen adsorptiondesorption isotherms, XRD, and zeta potential methods. Subsequently, puerarin (PUE) was used as the active ingredient and loaded into the three mesoporous materials, respectively. And, the drug delivery behavior was measured in PBS solution with different pH values. The sustained-release properties of MSN, DMSN, and HMSN loaded with PUE were investigated. Finally, the biocompatibility and stability of MSN, DMSN, and HMSN were studied by MTT assay and hemolysis assay. Our results showed that MSN, DMSN, and HMSN were successfully synthesized and the three types of mesoporous silica nanoparticles had higher drug loading and encapsulation efficiency. According to the first-order release equation curve and Higuchi equation parameters, the results showed that the PUE-loaded MSN, DMSN, and HMSN exhibited sustained-release properties. Finally, MTT and hemolysis methods displayed that MSN, DMSN, and HMSN had good biocompatibility and stability. In this study, MSN, DMSN, and HMSN were successfully synthesized, and to compare the drug release properties of nano-porous silica with different pore structures as a stroma for PUE drug, we provided a theoretical and practical basis for the application of PUE.

Thin-Film Composite Membrane with Porous Interlayer Composed of Dendritic Mesoporous Silica Nanoparticles for Enhanced Nanofiltration.

Positively charged nanofiltration (NF) membranes show great potential in the fields of water treatment and resource recovery. However, this kind of NF membrane usually suffers from relatively low water permeance. Herein, a positively charged NF membrane with a porous interlayer is developed, where the interlayer is formed by assembling dendritic mesoporous silica nanoparticles (DMSNs) after the formation of a polyamide layer. This post-assembly strategy avoids the adverse effect of the interlayer on the formation of positively charged NF membranes. The porous DMSN interlayer provides abundant connected channels for water transport, thus endowing the NF membrane with enhanced water permeance. A series of DMSNs with different sizes was synthesized, and their influence on membrane formation and membrane performance was systematically investigated. The optimized membrane exhibits a CaCl2 rejection rate of 95.2% and a water flux of 133.6 L·h-1·m-2, which is 1.6 times that of the control group without an interlayer. This work represents an approach to the fabrication of a positively charged NF membrane with porous interlayers for high-efficiency cation rejection.

Clearing intratumoral bacteria to augment tumor-therapeutic response by engineering antimicrobial dendritic mesoporous silica nanomedicine

As an important component of the tumor microenvironment, the intratumoral bacteria can significantly reduce the chemotherapeutic response, in which Fusobacterium nucleatum has been established as the representative intratumoral bacteria in colorectal cancer, promoting chemotherapy resistance by activating autophagy pathways. Herein, the concept of antibacterial-augmented antitumor nanomedicine for pathogen-related cancer therapy was elaborated by designing antibacterial-antineoplastic nanoagents that modulate intratumoral bacteria to augment anticancer efficiency. A generic coordination-redox strategy was used for homogeneous in situ growth of antibacterial ultrasmall silver nanoparticles into the dendritic mesoporous silica nanoparticles, which were further loaded with chemotherapeutic drugs. The antibacterial-antineoplastic agents exhibited excellent antitumor efficacy by scavenging Fusobacterium nucleatum to modulate autophagy, thereby overcoming chemoresistance to heighten the therapeutic effect. This work proposes a conceptual framework of antibacterial-augmented antitumor nanomedicine for refined cancer-therapeutic efficacy by modulating intratumoral bacteria to enhance therapeutic responses of chemotherapy, opening new horizons on nanomedicine design for more effective tumor therapy.

Cerium doped dendritic mesoporous bioactive glass nanoparticles with bioactivity and drug delivery capability

Dendritic mesoporous bioactive glass nanoparticles (DMBGNs) with unique three-dimensional structures are attracting increasing attention for biomedical applications. However, it is still challenging to tune the chemical composition of DMBGNs. In this work, we provide for the first time a feasible post-impregnation approach to incorporate metallic ions (Ca and Ce) into dendritic mesoporous silica nanoparticles, resulting in SiO2-CaO and SiO2-CaO-CeO2 (Ce-DMBGNs) without destroying the dendritic mesoporous topography. Both DMBGNs and Ce-DMBGNs were amorphous, negatively charged, with a hydrodynamic size of ∼200 nm. The synthesized DMBGNs and Ce-DMBGNs exhibited high bioactivity as evidenced by the rapid formation of hydroxyapatite (HA) after immersion in simulated body fluid (SBF) for 7 days. In addition, DMBGNs and Ce-DMBGNs showed high propolis loading efficiency and sustained release behavior. The results suggest that the developed Ce-DMBGNs have the potential to be used as a delivery vehicle of therapeutic ions and drugs in bone regeneration applications.

Zero-valent iron supported by dendritic mesoporous silica nanoparticles to purify dye wastewater

The presence of different types of organic dyes in water stream will clearly give rise to unexceptional side effects on living organisms. Emerging physical or chemical methods have been developed for the treatment of dye-involving water, but the exploration for adequate design strategy and technique available is still ongoing. Here, zero-valent iron (ZVI) was prepared by a liquid phase sodium borohydride reduction approach and then integrated with dendritic mesoporous silica nanoparticle (DMSN) to construct Janus magnetic adsorbent (denoted as ZVI-DMSN), which could be employed to purify dye wastewater. The structure, magnetic properties and dye adsorption results of ZVI-DMSN were systematically investigated. The ZVI component can enable efficient solid-liquid separation through magnetic separation route, and, more importantly, provided additional binding sites for adsorption process to increase the adsorption capacity. The thermodynamic analysis of adsorption indicated that the adsorption of typical organic dyes was an irreversible, spontaneous and endothermic process. Moreover, ZVI-DMSN adsorbent was recyclable, showing a regeneration efficiency of more than 80% after 5 cycles. We believe that ZVI-DMSN, as an inexpensive adsorbent material with excellent adsorption properties, e.g., short time, high efficiency and large capacity, will host vast potential for removal of dyes in water bodies.

Spatial distribution and proximity effect-dependent multi-enzyme cascades catalysis operating in dendritic mesoporous silica nanoparticles

Enzymatic cascades catalysis engenders complex and selective intracellular transformations due to the organization of the enzymes in confined cellular environments. In this work, a biomimetic strategy is employed to develop a synthetic cell analogue for operating multi-enzymatic cascade catalysis in vitro. The glucose peroxidase (GOx) and chloroperoxidase (CPO) are co-encapsulated in the channel of dendritic mesoporous silica nanoparticles (DMSP) modified by phase-transitioned lysozyme (PTL@GOx&CPO@DMSP). The cascade efficiency is substantially enhanced compared with the diffusion mixtures of the free enzymes in bulk solution due to some nanoscale construction, such as confinement effect, proximity effect and special distribution mode of the enzymes. The high specific surface area and high concentration of mesoporous cages in DMSP is beneficial for encapsulation of enzyme. The cross-linked cavities ensure directional transfer of the intermediate from GOx to CPO, known as “substrate channel”. PTL plays multiple functions including inhibiting leaking of enzyme from DMSP, concentrating intermediate H2O2 at DMSP domains and keeping this biocomposite stable in aqueous environment by improving its dispersibility. The prepared biocomposite PTL@GOx & CPO@DMSP is very stable at harsh conditions. It can retain 42% of original catalytic activity at 90°C with incubation for 3 h while the retained activity of free enzymes is only 5% under the same conditions. Meanwhile, it can keep 92.4% of its original catalytic activity after 10 reuses. These characteristics ensure practical application of this biocatalytic material. The active HClO generated by GOx-CPO cascade has an efficient anti-tumor effect and is effectively applied to preserve fruit.