Organosilica Precursor Research Articles

Biomimetic Trypsin-Responsive Structure-Bridged Mesoporous Organosilica Nanomedicine for Precise Treatment of Acute Pancreatitis.

Developing strategies to target injured pancreatic acinar cells (PACs) in conjunction with primary pathophysiology-specific pharmacological therapy presents a challenge in the management of acute pancreatitis (AP). We designed and synthesized a trypsin-cleavable organosilica precursor bridged by arginine-based amide bonds, leveraging trypsin's ability to selectively identify guanidino groups on arginine via Asp189 at the active S1 pocket and cleave the carboxy-terminal (C-terminal) amide bond via catalytic triads. The precursors were incorporated into the framework of mesoporous silica nanoparticles (MSNs) for encapsulating the membrane-permeable Ca2+ chelator BAPTA-AM with a high loading content (∼43.9%). Mesenchymal stem cell membrane coating and surface modification with PAC-targeting ligands endow MSNs with inflammation recruitment and precise PAC-targeting abilities, resulting in the highest distribution at 3 h in the pancreas with 4.7-fold more accumulation than that of naked MSNs. The outcomes transpired as follows: After bioinspired MSNs' skeleton biodegradation by prematurely and massively activated trypsin, BAPTA-AM was on-demand released in injured PACs, thereby effectively eliminating intracellular calcium overload (reduced Ca2+ level by 81.3%), restoring cellular redox status, blocking inflammatory cascades, and inhibiting cell necrosis by impeding the IκBα/NF-κB/TNF-α/IL-6 and CaMK-II/p-RIP3/p-MLKL/caspase-8,9 signaling pathways. In AP mice, a single dose of the formulation significantly restored pancreatic function (lipase and amylase reduced more by 60%) and improved the survival rate from 50 to 91.6%. The formulation offers a potentially effective strategy for clinical translation in AP treatment.

Development and characterization of magnetic-based biodegradable periodic mesoporous organosilica nanoparticles for enhanced biomedical applications

Herein, magnetic-based biodegradable periodic mesoporous organosilica (BPMO) nanoparticles were successfully synthesized via a co-precipitation method to form a magnetic iron oxide (Fe3O4) core, followed by the condensation of organosilica precursors to produce BPMO shells. The physicochemical properties of the resulting hybrid nanoparticles were evaluated using powder X-ray diffraction, nitrogen adsorption–desorption isotherms, thermogravimetric analysis, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. The synthesized particles exhibited a spherical morphology with an average diameter of approximately 250 nm. A core–shell structure was formed by depositing a 100-nm biodegradable organosilica layer onto the magnetic Fe3O4 cluster, endowing the nanoparticles with both magnetic and biodegradable mesoporous characteristics. Notably, despite the silica coating, the saturation magnetization remained high, reaching 35.8 emu/g, suggesting the potential for using these nanoparticles in magnetic-based biomedical applications. Furthermore, Fe3O4@BPMO nanoparticles were demonstrated to be efficiently uptaken by OVCAR8 ovarian cancer cells and spheroids, indicating that these nanoparticles are promising as magnetic nanocarriers for anti-cancer drug delivery and can be used in magnetic resonance imaging and magnetic hyperthermia.

Rigid-flexible coupled organosilica membranes toward high-efficiency molecules separation

Membrane-based technology has garnered significant interest in the separation and purification of molecules due to its inherent advantages, such as high efficiency, low energy consumption, and ease of operation. In this study, rigid-flexible coupled organosilica membranes were fabricated through co-polymerization using 1,2-bis(triethoxysilyl)acetylene (BTESA) containing rigid acetylene bridges and 1,2-bis(triethoxysilyl)propane (BTESP) containing flexible propane bridges. The incorporation of flexible propane bridges into BTESA networks allowed for precise adjustment of the network structures, resulting in composite BTESA-P membranes with improved molecular sieving properties. BTESA-P membrane demonstrated significant promise for applications in both CO2 capture and pervaporation (PV) dehydration due to its high potential. BTESA-P30 membrane, fabricated using the rigid-flexible coupled strategy, demonstrated a CO2 permeance of 3807 GPU and a CO2/N2 selectivity of approximately 40. These results surpassed those of numerous previously reported membranes, indicating significant potential for CO2 capture applications. BTESA-P30 membrane exhibited significant competitiveness in the decarbonization process of natural gas. More significantly, analogous occurrences are evident in gas permeation and PV separation process, where the permeation mechanism of gas and PV separation is primarily governed by molecular sieving. The utilization of diverse organosilica precursors in the rigid-flexible coupled strategy proposed in this study offers increased potential for membrane structure design and energy-efficient separation of molecules.

Network engineering of organosilica membranes for efficient pervaporation dehydration

In the petroleum industry, the mixing of ethanol (EtOH), isopropanol (IPA), and n-butanol (n-BuOH) with water is a prevalent occurrence in both production and recovery phases. Obtaining the required degree of purity via dehydration poses a significant challenge that needs to be addressed. Pervaporation has emerged as a promising method for separating azeotropic mixtures due to its energy efficiency and independence from vapor-liquid equilibrium constraints. In this study, organosilica precursors, namely 1,2-bis(triethoxysilyl)ethane (BTESE), 1,2-bis(triethoxysilyl)ethylene (BTESEthy), and 1,2-bis(triethoxysilyl)acetylene (BTESA), were utilized for the fabrication of organosilica membranes using the sol–gel method. Subsequently, these membranes were employed for pervaporation dehydration of EtOH, IPA, and n-BuOH. This study investigates the effect of the degree of unsaturation of the bridged group, feed composition, and C atom count of alcohol on membrane dehydration performance. The membranes demonstrated superior separation performance for the n-butanol/water mixtures compared to other alcohol/water systems investigated. In this particular context, BTESE membrane exhibited a significant separation factor, although accompanied by a reduced permeation flux. Conversely, BTESA membrane demonstrated a decreased separation factor but an increased permeation flux. The comparison between gas permeation and pervaporation highlighted that the separation mechanism was primarily governed by molecular sieving through the organosilica membranes.

Tailoring pore size of mesoporous silica and organosilica using biodegradable pentablock copolymer templates via EISA process

In this work, we have designed unique poly(lactic acid-co-glycolic acid)-b-poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide)-b-poly(lactic acid-co-glycolic acid) pentablock copolymers using Pluronic F68 and F108 triblock copolymers as macroinitiators. The poly(lactic acid-co-glycolic acid) (PLGA) blocks were attached as glycolide and lactide monomers at the both ends of each F68 and F108 triblock copolymer. The molecular weights and the block fractions were confirmed by gel permeation chromatography (GPC) and proton nuclear magnetic resonance (1H NMR) for the four kinds of pentablock copolymers. Using these pentablock copolymers as templates, we synthesized mesoporous ethane-silicas as well as silicas by the evaporation-induced self-assembly (EISA) method. 1,2-bis(triethoxysily)ethane (BTEE) were used as an organosilica precursor. The mesoporous ethane-silica samples were characterized using synchrotron small angle X-ray scattering (SAXS), nitrogen sorption experiments, transmission electron microscopy (TEM), and solid-state 29Si CP-MAS NMR. Based on the experimental results, it was confirmed that the porosity and pore diameter can be varied with the PLGA weight fraction of the pentablock copolymer. It is due to the PLGA block in polymer forming the hydrophobic domain in micelles, which leads to the formation of increased pore size over 20 nm without any additive pore expander. In addition, it seems that as the organosilica precursor increases, the association number of block copolymers forming one micelle decreases, resulting in a decrease in pore size. In summary, the polymer template plays a vital part in tuning the structure of the mesoporous ethane-silica samples. Thus, the development of synthetic method of mesoporous organosilica materials using polymer templates with different topology is still challenging and can endow the unique structure and property for mesoporous organosilica for future applications.

Preparation of phenyl-bridged hybrid organic-inorganic mesoporous vesicles with high thermal stability and hierarchical buildups

Hollow periodic mesoporous organosilicas have promising applications due to their excellent properties but have difficulty withstanding harsh working conditions, and current synthesis techniques typically require strong acids or strong base substances. In this study, we report an environmentally friendly synthesis technique of phenyl-bridged hybrid organic-inorganic mesoporous vesicles (Ph-HPMOs) with high thermal stability and hydrothermal stability using 1,4-bis(triethoxysilyl)benzene (BTEB) as an organosilica precursor in alkaline phosphate buffer solution. The Ph-HPMOs were robust with a diameter of 100–200 nm and a shell thickness up to 50 nm. In addition, the Ph-HPMOs had a unique hierarchical pore size distribution of macropores, cavities, mesopores and micropores with a high surface area of 560–930 m2/g and a large pore volume of 0.6–1.3 cm3/g. Also, the effect of different variables on the structural morphologies of the products were investigated. The optimized conditions for the Ph-HPMOs were 1 SDS:1.5 CTAB: 13.575 BTEB: 4.525 TEOS: 316.26 EtOH: 5119.92H2O (molar ratio). Additionally, aluminum ions (Al3+) were doped into Ph-HPMOs, and the catalytic properties were investigated in a fixed bed reactor, highlighting their high practical value as catalysts or adsorbents.

New insight into multiple hydrogen-bond networks of functional organosilicas system for collaborative transformation of CO2 under mild conditions

It is challenging to integrate various active species into porous materials in an organized manner to realize efficient and synchronous CO2 adsorption and chemical conversion. Here multiple Lewis base and dual hydrogen bond donor (HBD) units were integrated into an organosilicon precursor, and novel triazine and hydrazo sites co-modified periodic mesoporous organosilicas (THPMOs) were prepared via a simple hydrothermal self-assembly method. The morphological structures of THPMOs with different contents of active sites were characterized. The THPMOs displayed high BET surface areas (699–876 m2/g) and favorable low-pressure CO2 adsorption capacities at 273 K. When combined with tetrabutylammonium iodide (TBAI), they promoted the model cycloaddition of CO2 and propylene oxide (PO) effectively. By regulating the molar ratios of organosilica precursors, the obtained THPMO-25 catalyzed this reaction and produced a 96 % propylene carbonate (PC) yield under mild conditions. Moreover, the THPMO-25 was applicable using various epoxides and also exhibited satisfactory structural stability during recycling. Combined with theoretical calculations, an insight into the reaction mechanism involving multiple hydrogen-bond interactions was provided. The robust and recyclable nanomaterials offer an attractive approach for CO2 adsorption and subsequent chemical synthesis of organic carbonate.

Sub-nanometer scale tailoring of the microstructures of composite organosilica membranes for efficient pervaporation of toluene/n-heptane mixtures

Amorphous organosilica-based membranes are of enormous potential for pervaporation separation of organic mixtures, however, engineering organosilica membranes with the on-demand pore size and functionality for precise molecular sieving still remains a challenge. Herein, as a proof-of-concept, we proposed a facile and novel co-condensation strategy by pairing the biphenyl-bridged organosilica precursor (BTESBP) with another organosilica precursor (PhTES) equipped with a phenyl pendant group for efficient pervaporation of aromatic/aliphatic mixtures. It was demonstrated that the strong aromatic π-π interactions between BTESBP and PhTES as well as the steric hindrance effect of PhTES allowed the tailoring of membrane pore size at the sub-nano scale, and enhanced the accessibility of biphenyl groups to aromatic hydrocarbons. At the optimal BTESBP/PhTES mass ratio of 98/2, the resulting BTESBP/PhTES composite organosilica membrane achieved superior toluene/n-heptane pervaporation separation performance with a total flux surpassing 1 kg m−2 h−1 and a separation factor of 8–10 for a 50 wt% toluene/n-heptane feed mixture. Hopefully, this study can stimulate the rethinking of the design principles for composite organosilica membranes and the subsequent development of advanced membranes for energy-efficient pervaporation of organic mixtures.

Architecture of Nanoantioxidant Based on Mesoporous Organosilica Trp-Met-PMO with Dipeptide Skeleton.

A nanoantioxidant of mesoporous organosilica (Trp-Met-PMO) based on the framework of tryptophan-methionine dipeptide was first designed and constructed by condensation between self-created dipeptide organosilica precursor (Trp-Met-Si) and tetraethyl orthosilicate (TEOS) in alkaline conditions under the template hexadecyl trimethyl ammonium bromide (CTAB). Trp-Met-Si was prepared by the reaction between dipeptide Trp-Met and conventional organosilicon coupling agent isocyanatopropyltriethoxysilane (IPTES) via a multiple-step reaction method. The material Trp-Met-PMO was confirmed by XRD, FT-IR and N2 adsorption-desorption analysis. The material Trp-Met-5-PMO with low amounts of organosilica precursor remained a mesoporous material with well-ordered 2D hexagonal (P6mm) structure. With increasing amounts of organosilica precursor, a mesoporous structure was still formed, as shown in the material Trp-Met-100-PMO with the highest amounts of organosilica precursor. Moreover, pore size distribution, surface area and porosity of Trp-Met-PMO are regulated with different amounts of organosilica precursor Trp-Met-Si. The antioxidant activity of Trp-Met-PMO was evaluated by ABTS free radical-scavenging assay. The results showed that antioxidant activity was largely enhanced with increasing contents of organosilica precusor Trp-Met-Si in the skeleton. The material Trp-Met-40-PMO exhibited maximum scavenging capacity of ABTS free radicals, the inhibition percent was 5.88%. This study provides a design strategy for nanoantioxidant by immobilizing short peptides within the porous framework of mesoporous material.

Synthesis of mesoporous organosilica nanoparticles with a high tetrasulphide content and large pores

Tetrasulphide bridged mesoporous organosilica nanoparticles (MONs) with a high sulphur content of ∼11% and a large pore size of ∼14 nm have been synthesized using tetrabutyl orthosilicate (TBOS) as a modulator in the synthetic system. It is shown that the incorporation of TBOS modulates the hydrolysis and co-condensation of inorganic silica and organosilica precursors during the formation of MONs, leading to a higher organosilica content and larger mesopores compared with the conventional synthesis using only tetraethyl orthosilicate (TEOS) as the inorganic silica precursor. Moreover, MONs with a high tetrasulphide content exhibit enhanced GSH oxidation capability, showing their potential in applications where GSH depletion is important.

Tuning the Properties of Chiral Nematic Mesoporous (Organo)silica Through Thiol‐Ene Click Chemistry

AbstractChiral nematic mesoporous silica and organosilica have iridescent properties that make them attractive for decoration and sensing. The limited number of commercial organosilica precursors available to create these materials has meant that they have a limited range of chemical and mechanical properties. In this paper, we incorporate vinyl groups in the mesoporous (organo)silica materials and demonstrate their functionalization with thiols through the thiol‐ene click reaction. In this way, we have been able to access chiral nematic mesoporous materials with different functional groups on the surface. We demonstrate that the hydrophobicity of the materials can be tuned, enabling detection of mixtures of organic solvents in water as well as showing promise for ion sequestration.

Stable Encapsulation of Methylene Blue in Polysulfide Organosilica Colloids for Fluorescent Tracking of Nanoparticle Uptake in Cells.

Methylene blue (MB), a century-old drug and a fluorescent dye, has a long history of diverse applications, both in drug therapy and as a tissue-staining agent. However, MB is inherently unstable when exposed to light and reducing agents. In this study, we aim to prepare and characterize polysulfide-based organosilica colloidal particles for efficient, stable, and protective encapsulation of MB. Disulfide- and tetrasulfide-containing organosilane congeners were used as organosilica precursors for direct synthesis of organosilica colloids based on the silica ouzo effect. MB was spontaneously entrapped into the colloidal particles during the particle formation process. The following properties of the colloidal MB were evaluated: particle size, surface charge, atomic distribution, encapsulation efficiency, MB release, photodynamic activity, thiol and ascorbate reactivity, and cytotoxicity. The DLS measurements show that the size of colloidal MB is tunable in a range of 100 nm to 1 μm. SEM images reveal spherical particles with composition-dependent particle sizes of 70–120 nm (coefficient of variation: 15–18%). MB was encapsulated in the colloidal particles with a maximal efficiency of 95%. The release of MB from the colloids was <1% at 4 h and <3.5% at 48 h. The colloidal particles show much reduced photodynamic activity, low reactivity toward reducing agents, and low cytotoxicity. Accordingly, the colloidal MB was proposed and further investigated as a fluorescent particle tracer for the study of cell–nanoparticle interactions. In conclusion, MB can be efficiently and stably loaded into polysulfide organosilica colloidal particles using a simple and convenient physical route.

Boosting the CO2 capture efficiency through aromatic bridged organosilica membranes

CO2 capture have attracted much attention due to serious environmental problems caused by excessive CO2 emission. Membrane-based technologies boasting of energy-saving and high-efficiency advantages exhibit much prospect in treating this issue. Benefited from excellent molecular sieving properties and high porosity, a wide variety of organosilica membranes were applied to the CO2 separation process. Nevertheless, most studies focused on the development of linear alkanes bridged organosilica membranes. Few researchers were dedicated to developing organosilica membranes with aromatic groups. In fact, the aromatic groups (e.g., such as benzene groups) functionalized organosilica precursors can endow derived membranes with robust network structures. Moreover, aromatic benzene groups can provide infinite possibilities of decoration. Herein, organosilica membranes fabricated using phenyltriethoxysilane (PhTES) with pendant benzene group, bis(triethoxysilyl)benzene (BTESB) with bridged benzene group and 4,4′-bis(triethoxysilyl)-1,1′-biphenyl (BTESBPh) with bridged biphenyl group, were used for CO2 capture separation. The effect of the location of aromatic benzene groups (bridged or pendant type) and the number of aromatic bridges (single benzene and biphenyl bridges) were evaluated in detail. For CO2/N2 mixtures separation at 50 °C, PhTES membranes displayed a CO2 permeance of 1087 GPU (1GPU = 3.348 ✕ 10−10 mol m−2 s−1 Pa−1) and CO2/N2 selectivity of 30. In contrast, BTESB membranes maintained a similar level of CO2/N2 selectivity of 34 but approximately 2.5 times enhanced CO2 permeance of 2600 GPU. BTESBPh membranes featured an unprecedentedly high CO2 permeance of 5465 GPU and CO2/N2 selectivity of 13. This clearly indicated that the aromatic functionalized organosilica membranes presented great potential in CO2 capture applications. Furthermore, the gas permeation properties of organosilica membranes can be finely tuned via the change of the location and the number of the benzene groups.

Microporous Nickel-Coordinated Aminosilica Membranes for Improved Pervaporation Performance of Methanol/Toluene Separation.

The nickel-doped bis [3-(trimethoxysilyl) propyl] amine (BTPA) derived membrane has a microporous coordinated network that has high potential to be an ideal separation barrier for methanol-toluene azeotropic mixtures via the pervaporation process. Ni-BTPA membranes were modified by employing a nickel dopant over amine groups in mole ratios (mol/mol) that ranged from 0.125 to 0.50. The incorporation of different amounts of nickel dopant into flexible amine-rich organosilica precursors of BTPA increased the rigidity and resulted in a porous structure with a large specific surface area (increased from 2.36 up to 282 m2 g-1) and a high pore volume (from 0.024 up to 0.184 cm3 g-1). Methanol-toluene separation performance by the nickel-doped BTPA (Ni-BTPA) membranes was increased with increases in the nickel concentration. Ni-BTPA 0.50 showed separation performance that was superior to other types of membranes, along with a high-level of flux at 2.8 kg m-2 h-1 and a separation factor higher than 900 in a 10 wt % methanol feed solution at 50 °C. These results suggest that the balance between the microporosity induced by amine-nickel coordination and an excessive amount of nickel-ion facilitates high levels of flux and separation of methanol.

Benzene-Bridged Organosilica Modified Mesoporous Silica Nanoparticles via an Acid-Catalysis Approach.

Surface functionalization of mesoporous silica nanoparticles is important for their applications but fairly challenging using benzene-bridged organosilane as the precursor through the postsynthesis approach. Herein, we report an acid-catalysis approach for the postmodification of benzene-bridged organosilica onto the surface of large-pore mesoporous silica nanoparticles. By using HCl (∼1 M) as the acid catalyst in a tetrahydrofuran solvent, the self-assembly of the bridged organosilica precursor is avoided, while surface modification of mesoporous silica nanoparticles is promoted with controllable organic contents and retained large pore sizes. This strategy can also be applied to the postmodification of organosilica with end benzene groups. The strategy developed in this study is expected to be applied for the postmodification of other organosilica precursors with various functions.

Surfactant-free synthesis of monodispersed organosilica particles with pure sulfide-bridged silsesquioxane framework chemistry via extension of Stöber method

Sulfide bond incorporated organosilica particles have been broadly applied to versatile biomedical applications, wherein the uniformity of particles and the sulfur content significantly dictate the ultimate performance. Unfortunately, due to the difficulty in controlling the chemical behavior of organosilica precursors in a sol–gel process, challenges still exist in developing a facile and green synthetic approach to fabricate organosilica particles with good dispersity and high sulfur content. In the present work, by extending the classic Stöber method, a surfactant-free synthesis of monodispersed organosilica particles with pure sulfide-bridged silsesquioxane framework chemistry is reported for the first time. By simply tailoring the ethanol-to-water ratio and amount of catalyst, the size of disulfide-bridged organosilica particles can be tuned from ~0.50 to ~1.20 µm. Moreover, this approach can be employed to prepare tetra-sulfide bridged silica nanoparticles with an extremely high sulfur content of 30.7 wt% and negligible cytotoxicity. Notably, taking advantage of this extended Stöber method, both hydrophilic (methylene blue) and hydrophobic (curcumin) molecules can be in-situ encapsulated into tetra-sulfide bridged silica nanoparticles, whose glutathione-triggered biodegradability is also demonstrated. Collectively, the innovative synthetic approach and organosilica particles developed in this work are expected to open up new opportunities in hybrid materials fabrication and bio-applications.

Electrospinning Superassembled Mesoporous AIEgen-Organosilica Frameworks Featuring Diversified Forms and Superstability for Wearable and Washable Solid-State Fluorescence Smart Sensors.

Flexible optical sensors are widely studied and applied in many fields. However, developing highly stable and washable wearable sensors in optics is still facing significant challenges. Here, we demonstrate an AIEgen-organosilica framework (TPEPMO) hybrid nanostructure-based flexible optical sensor, which is prepared by a two-step co-condensation and electrospinning superassembly process. Organosilica precursors with aggregation-induced emission (AIE) features are covalently linked into periodic mesoporous organosilica (PMO) frameworks with high fluorescent efficiency due to the restriction of intramolecular motion. The three-dimensional space of ordered porous materials provides abundant reaction sites, allowing rapid and sensitive monitoring of analytes. TPEPMOs exhibit good properties as acidic pH fluorescent sensors with a pKa of 4.3. A flexible film is obtained by dispersing TPEPMO nanospheres in a poly(lactic-co-glycolic acid) (PLGA) and polyacrylonitrile (PAN) hybrid fibrous matrix (TPEPMO-CFs) using the electrospinning superassembly technique and is successfully served as an efficient fluorescent probe for the naked eye detection of ammonia gas and HCl vapor by emission changes. The fluorescence of TPEPMO-CFs can be reversed in the presence of volatile acidic/alkaline gas for more than five cycles, exhibiting excellent recyclability. In addition, TPEPMO-CF sensors show excellent washability and long-term photostability (fluorescence was maintained above 94% after washing 10 times). These stimuli-responsive AIEgen-organosilica frameworks featuring diversified forms and superstability for wearable and washable solid-state fluorescence exhibit great potential for smart gas sensors, wearable devices, and solid-state lighting applications.

Hollow mesoporous organosilica nanospheres with multiple tiny silver nanoparticles: A polymer mediated growth approach and catalytic application

The fabrication of nanostructured catalysts based on noble metal nanoparticles has attracted much attention. In this study, multiple tiny Ag nanoparticles loaded hollow mesoporous organosilica spheres (MT-Ag@HMOS) were synthesized by a novel polymer mediated growth approach. During the preparation, polyacrylic acid@hollow mesoporous organosilica spheres (PAA@HMOS) were first produced formed by condensation of organosilica precursor on polyacrylic acid (PAA) colloids; subsequently, tiny Ag nanoparticles were in situ immobilized both in the cavity and on the shell of PAA@HMOS due to their abundant thioether groups and unique structure. The produced materials were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), N2 adsorption-desorption instruments, X-ray diffraction (XRD), and X-ray photoelectron spectra (XPS). The MT-Ag@HMOS exhibited a spherical morphology with an average diameter of about 120 nm, a high surface area of 76.5 m2·g−1, as well as high content of tiny Ag nanoparticles (approximately 3 nm). In addition, the catalytic activities of the MT-Ag@HMOS on 4-nitrophenol (4-NP), Congo red (CR), and Rhodamine B (RhB) reduction in the presence of NaBH4 in aqueous medium were investigated. Experimental results show MT-Ag@HMOS particles are promising candidates for the treatment of waste water supplemented contaminated by 4-NP and various dyes.

Hydrocarbon permeation properties through microporous fluorine-doped organosilica membranes with controlled pore sizes

F-BTESM membranes were fabricated by doping a fluorine source into bis(triethoxysilyl)methane (BTESM), which is an organosilica precursor composed of Si–CH2–Si bonds. Pore size controllability and C3–C4 hydrocarbon permeation properties for F-BTESM membranes with different concentrations of fluorine were evaluated using single-gas permeation and N2/C3–C4 hydrocarbon binary separation. The pore size of an organosilica membrane can be precisely controlled via doping with the correct concentration of fluorine. The molecular sieving properties for C3/C4 hydrocarbon separation such as that for C3H6/iso-C4H8 was dramatically enhanced with the addition of a fluorine concentration of F/Si = 0.05, and this membrane showed a C3H6/iso-C4H8 permeance ratio of 388 at 50 °C. The permeance of hydrocarbon gases was increased with an expansion of the pore size, and F-BTESM (F/Si = 0.15) showed a high level of C3H6 permeance (>5.0 × 10−7 mol m−2 s−1 Pa−1). The results of hydrocarbon adsorption and single permeation properties showed that the carbon number of the hydrocarbons and the presence of unsaturated bonds enhanced the adsorption affinity to silica-derived materials. In the binary separation of N2/C3–C4 hydrocarbons, N2 permeance was remarkably decreased by comparison with single-gas permeation, which was due to a blocking effect by the hydrocarbons adsorbed inside the pores. Hydrocarbon gases with a stronger affinity tended to inhibit the permeation of N2.

General and facile syntheses of hybridized deformable hollow mesoporous organosilica nanocapsules for drug delivery

Deformable materials have garnered widespread attention in biomedical applications. Herein, a controllable, general, and simple alkaline etching strategy was used to synthesize deformable hollow mesoporous organosilica nanocapsules (DMONs), in which multiple organic moieties were homogeneously incorporated into the framework. DMONs with double-, triple-, and even quadruple-hybridized frameworks were prepared by the selective introduction of organosilica precursors in accordance with the chemical homology principle through a surfactant-directed sol–gel procedure and a subsequent etching process in alkaline solution. The triple-hybridized DMONs possessed uniform and controllable diameters (100–330 nm), and large hollow cavities (50–270 nm). Liquid cell electron microscopy images demonstrated that the DMONs were deformable in solution. Elemental mapping images suggested that the organic components were homogeneous distribution within the entire DMONs framework. Statistical analysis of cell proliferation assays showed that breast cancer MCF-7 viability exceeded 85% when the cells are incubated with the triple-hybridized DMONs (800 μg mL−1) for 24 h. Histological assessments of main organs indicated no tissue injury or necrosis after intravenous injection of the DMONs 7 days (5 mg kg−1 body weight). Quantitative analysis indicated that the cellular uptake of the DMONs was 6-fold higher than that of their hard counterparts when the number of nanoparticles added was 1.25 × 104, and similar results were found for 4 T1 cells. Furthermore, doxorubicin (DOX) loaded triple-hybridized DMONs with a loading efficiency of 16.9 wt%, produced a strong killing effect on tumor cells. Overall, DMONs with various incorporated organic functional groups could serve as novel nanoplatforms for drug delivery in biomedical applications.