Dual-Functional Ultrafiltration Membrane for Simultaneous Removal of Multiple Pollutants with High Performance.

Simultaneous removal of multiple pollutants from aqueous solution with less energy consumption is crucial in water purification. Here, a novel concept of dual-functional ultrafiltration (DFUF) membrane is demonstrated by entrapment of nanostructured adsorbents into the finger-like pores of ultrafiltration (UF) membrane rather than in the membrane matrix in previous reports of blend membranes, resulting in an exceptionally high active content and simultaneous removal of multiple pollutants from water due to the dual functions of rejection and adsorption. As a demonstration, hollow porous Zr(OH)x nanospheres (HPZNs) were immobilized in poly(ether sulfone) (PES) UF membranes through polydopamine coating with a high content of 68.9 wt %. The decontamination capacity of DFUF membranes toward multiple model pollutants (colloidal gold, polyethylene glycol (PEG), Pb(II)) was evaluated against a blend membrane. Compared to the blend membrane, the DFUF membranes showed 2.1-fold increase in the effective treatment volume for the treatment of Pb(II) contaminated water from 100 ppb to below 10 ppb (WHO drinking water standard). Simultaneously, the DFUF membranes effectively removed the colloidal gold and PEG below instrument detection limit, however the blend membrane only achieved 97.6% and 96.8% rejection for colloidal gold and PEG, respectively. Moreover, the DFUF membranes showed negligible leakage of nanoadsorbents during testing; and the membrane can be easily regenerated and reused. This study sheds new light on the design of high performance multifunction membranes for drinking water purification.

Kinetically Controlled Assembly of Nitrogen-Doped Invaginated Carbon Nanospheres with Tunable Mesopores.

Mesoporous hollow carbon nanospheres (MHCS) have been extensively studied owning to their unique structural features and diverse potential applications. A surfactant-free self-assembly approach between resorcinol/formaldehyde and silicon alkoxide has emerged as an important strategy to prepare MHCS. Extending such a strategy to other substituted phenols to produce heterogeneous-atom-doped MHCS remains a challenge due to the very different polymerization kinetics of various resins. Herein, we report an ethylenediamine-assisted strategy to control the cooperative self-assembly between a 3-aminophenol/formaldehyde resin and silica templates. Nitrogen-doped mesoporous invaginated carbon nanospheres (N-MICS) with an N content of 6.18 at %, high specific surface areas (up to 1118 m2 g-1 ), large pore volumes (2.47 cm3 g-1 ), and tunable mesopores (3.7-11.1 nm) have been prepared. When used as electrical double-layer supercapacitors, N-MICS show a high capacitance of 261 F g-1 , an outstanding cycling stability (≈94 % capacitance retention after 10 000 cycles), and a good rate performance.

Core-Cone Structured Monodispersed Mesoporous Silica Nanoparticles with Ultra-large Cavity for Protein Delivery.

A new type of monodispersed mesoporous silica nanoparticles with a core-cone structure (MSN-CC) has been synthesized. The large cone-shaped pores are formed by silica lamellae closely packed encircling a spherical core, showing a structure similar to the flower dahlia. MSN-CC has a large pore size of 45 nm and a high pore volume of 2.59 cm(3) g(-1). MSN-CC demonstrates a high loading capacity of large proteins and successfully delivers active ß-galactosidase into cells, showing their potential as efficient nanocarriers for the cellular delivery of proteins with large molecular weights.

Sensitive detection of human insulin using a designed combined pore approach.

A unique combined pore approach to the sensitive detection of human insulin is developed. Through a systematic study to understand the impact of pore size and surface chemistry of nanoporous materials on their enrichment and purification performance, the advantages of selected porous materials are integrated to enhance detection sensitivity in a unified two-step process. In the first purification step, a rationally designed large pore material (ca. 100 nm in diameter) is chosen to repel the interferences from nontarget molecules. In the second enrichment step, a hydrophobically modified mesoporous material with a pore size of 5 nm is selected to enrich insulin molecules. A low detection limit of 0.05 ng mL(-1) in artificial urine is achieved by this advanced approach, similar to most antibody-based analysis protocols. This designer approach is efficient and low cost, and thus has great potential in the sensitive detection of biomolecules in complex biological systems.

Effect of surface functionality of silica nanoparticles on cellular uptake and cytotoxicity.

Mesoporous silica nanoparticles (MCM-41) with different surface chemistry were used as carrier system to study its influence on drug delivery and anticancer activity of curcumin (CUR). CUR was encapsulated in pristine MCM-41 (hydrophilic and negatively charged), amino functionalized MCM-41 (MCM-41-NH2 which is hydrophilic and positively charged), and methyl functionalized MCM-41 (MCM-41-CH3 which is hydrophobic and negatively charged) and evaluated for in vitro release and cell cytotoxicity in human squamous cell carcinoma cell line (SCC25). Various techniques were employed to evaluate the performance of these materials on cellular uptake and anticancer activity in the SCC25 cell line. Both positively and negatively charged surfaces demonstrated enhanced drug release and anticancer activity compared to pure CUR. Positively charged nanoparticles showed higher cell uptake compared to negatively charged nanoparticles owing to its electrostatic interaction with cells. However, hydrophobic surface modified nanoparticles (MCM-41-CH3) showed no improvement in drug release and anticancer activity due to its poor wetting effect. Cell cycle analysis and cell apoptosis studies revealed different pathway mechanisms followed by the positively and negatively charged nanoparticles but exhibiting similar anticancer activity in SCC25 cells.

Bottom-up self-assembly of heterotrimeric nanoparticles and their secondary Janus generations.

A bottom-up self-assembly approach is developed for the synthesis of ABC type heterotrimeric nanoparticles, which can be converted into secondary Janus-type silica derivatives. Compared to spherical ones, Janus silica nanoparticles stimulate stronger phagocytosis and transcytosis through intestinal epithelial microfold cells and exhibit higher cargo transport across an in vitro epithelial monolayer model mimicking the human intestinal epithelium.

Rechargeable aluminum-selenium batteries with high capacity.

Rechargeable aluminum (Al) batteries are emerging as a promising post lithium-ion battery technology. Herein, we demonstrate a conceptually new design of rechargeable aluminum-selenium (Al-Se) batteries by understanding the selenium chemistry and controlling the electrode reaction. The Al-Se battery consists of a composite cathode including selenium nanowires and mesoporous carbon (CMK-3) nanorods, an Al metal anode and chloroaluminate ionic liquid electrolyte. The working mechanism of the Al-Se battery is the reversible redox reaction of the Se2Cl2/Se pair confined in the mesopores of CMK-3 nanorods. Al-Se batteries deliver a high reversible capacity of 178 mA h g-1 (by Se mass), high discharge voltages (mainly above 1.5 V), and good cycling/rate performances.

Rattle-type magnetic mesoporous hollow carbon as a high-performance and reusable adsorbent for water treatment.

Rattle-type magnetic mesoporous hollow carbon (RMMHC) materials have shown great promise as adsorbents for water treatment. In this work, we report a surfactant-free synthesis of RMMHC nanoparticles (NPs) using magnetite NPs as the core, tetrapropyl orthosilicate, resorcinol and formaldehyde to form the shell followed by carbonization and selective silica etching. The pore size, specific surface area and pore volume of RMMHC NPs can be tuned by varying the carbonization temperature (500, 700 and 900 °C). At the optimized temperature of 700 °C, the RMMHC NPs possess the highest specific surface area of 579 m2 g-1, the largest pore volume of 0.795 cm3 g-1, and the largest pore size of 7.6 nm among all three samples. The adsorption capacity of optimized RMMHC NPs towards di (2-ethylhexyl) phthalate (a model organic pollutant) reaches as high as 783.1 mg g-1. Taking advantage of the magnetic property, the adsorbents retain more than 87% of their initial adsorption capacity over five times' reuse.

Surfactant-Free Assembly of Mesoporous Carbon Hollow Spheres with Large Tunable Pore Sizes.

Mesoporous carbon hollow spheres (MCHS) have wide applications, including catalysis, absorption, and energy storage/conversion. Herein, we report a one-pot, surfactant-free synthesis of MCHS using three molecules: resorcinol, formaldehyde, and tetrapropyl orthosilicate. The co-condensation process between the in situ generated silica primary particles and the polymer oligomers is regulated, leading to monodispersed MCHS with adjustable pore sizes from micropores to 13.9 nm. The resultant MCHS shows excellent performance for electrochemical double-layer capacitors with high capacitance (310 F g(-1) at 1 A g(-1)), excellent rate capability (157 F g(-1) at 50 A g(-1)), and outstanding cycling stability (98.6% capacity retention after 10 000 cycles at 10 A g(-1)). Our one-pot synthesis strategy is versatile and can be extended to fabricate metal oxide@mesoporous carbon yolk-shell structures in the absence of surfactant, paving the way toward designed synthesis of nanostructured mesoporous carbon composites for various applications.

Mesoporous Magnesium Oxide Hollow Spheres as Superior Arsenite Adsorbent: Synthesis and Adsorption Behavior.

Arsenic contamination in natural water has posed a significant threat to global health due to its toxicity and carcinogenity. Adsorption technology is an easy and flexible method for arsenic removal with high efficiency. In this Article, we demonstrated the synthesis of mesoporous MgO hollow spheres (MgO-HS) and their application as high performance arsenite (As(III)) adsorbent. MgO-HS with uniform particle size (∼180 nm), high specific surface area (175 m(2) g(-1)), and distinguished mesopores (9.5 nm in size) have been prepared by hard-templating approach using mesoporous hollow carbon spheres as templates. An ultrahigh maximum As(III) adsorption capacity (Qmax) of 892 mg g(-1) was achieved in batch As(III) removal study. Adsorption kinetic study demonstrated that MgO-HS could enable As(III) adsorption 6 times faster as a commercial MgO adsorbent. The ultrahigh adsorption capacity and faster adsorption kinetics were attributed to the unique structure and morphology of MgO-HS that enabled fast transformation into a flower-like porous structure composed of ultrathin Mg(OH)2 nanosheets. This in situ formed structure provided abundant and highly accessible hydroxyl groups, which enhanced the adsorption performance toward As(III). The outstanding As(III) removal capability of MgO-HS showed their great promise as highly efficient adsorbents for As(III) sequestration from contaminated water.

Mesoporous materials modified by aptamers and hydrophobic groups assist ultra-sensitive insulin detection in serum.

A novel mesoporous material modified with both insulin-binding-aptamers and hydrophobic methyl groups is synthesized. With rationally designed pore structures and surface chemistry, this material is applied in sample pre-treatment for ELISA, and enables the quantification (0.25-5 pg ml(-1)) of insulin in serum, 30-fold enhancement of the limit-of-detection compared to the commercial ELISA kit.

Applications of nanomaterials in mass spectrometry analysis.

Mass spectrometry (MS) based analyses have received intense research interest in a series of rapidly developing disciplines. Although current MS techniques have enjoyed great successes, several key challenges still remain in practical applications, especially for the detection of biomolecules in biological systems. The use of nanomaterials in MS based analysis provides a promising approach due to their unique physical and chemical properties. In this review, nanomaterials with different compositions and nanostructures employed in MS applications are summarised and classified by their functions. Such an integrated and wide reaching review will provide a comprehensive handbook to researchers with various backgrounds working in this exciting interdisciplinary area.