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A novel polyoxometalate (POM)-based hybrid is prepared for the selective adsorption of acidic and/or basic proteins. The solidification of the POM moiety P8W48 is firstly achieved through dehydration condensation between the –OH group on the P8W48 surface and the Si–OH of aminopropyltriethoxysilane (APTS), and thereafter further condensation of the P8W48O184–APTS intermediate with poly(acrylic acid) (PAA) produces a hybrid, by linking carboxyl groups in PAA with –NH2 groups in P8W48O184–APTS via the formation of an amide bond. The P8W48–APTS–PAA hybrid surface is negatively charged due to abundant COO− groups from PAA, which provides electrostatic interactions with positively charged proteins by varying pHs. Meanwhile, the d–p π bond in P8W48 offers strong affinity to other proteins via π–π stacking interaction. The hybrid thus offers potential for achieving selective adsorption of either acidic or basic proteins by simply controlling the adsorption conditions, i.e., pH value or ionic strength of the adsorption medium. With ovalbumin (Ova) and lysozyme (Lys) as the models of acidic and basic proteins, their adsorption behaviors fit the Langmuir model, with adsorption capacities of 367.0 mg g−1 and 74.0 mg g−1, respectively. The retained proteins are readily recovered with 0.01 mol L−1 CTAB, providing recoveries of 89.0% for Ova and 93.0% for Lys. The P8W48–APTS–PAA hybrid is further applied for the isolation of Ova and Lys from real biological samples, egg white.

We identified that the growth kinetics of ZrO2 could be well-tuned in a CH3COOH-CH3COONa based buffer solution, which provided an efficient way to build uniform ZrO2 nanoshells on various substrates. Using this synthetic strategy, yolk-shell structured Pd@ZrO2 is demonstrated as a promising catalyst for methane oxidation.

One-part geopolymer precursors are synthesized and preliminarily optimized by calcining bentonite with NaOH or Na 2 CO 3 to compare with the two-part ones. The ground powders of the former are hydrated by only adding water at 80 °C for 3 days and 20 °C for subsequent time. Some one-part geopolymers gain satisfying compressive strengths and are quite water-resistant similar to the two-part ones. It is found that alkali alters and deepens the thermal decomposition of the bentonite and transforms quartz impurity into X-ray amorphous cementing-active glassy phases. Nepheline is usually generated in the alkali-fused bentonite, and gehlenite also occurs when calcined at 1000 °C. Different kinds of zeolites appear in the one-part geopolymers, while the calcium ferrites, only found in the precursors exclusively activated by Na 2 CO 3 , lead to produce additional hydrous gehlenite, so Na 2 CO 3 seems facilitates hydration more effective than NaOH given the pastes from the precursors calcined with Na 2 CO 3 possess higher compressive strengths. Moreover, the ferric oxide and calcium oxide have potential to enhance the cementing properties according to the mechanisms with calcination and hydration. The low hydrolysis rate might lead to poor water-resistance and the softening coefficient of the pastes increases with alkali content and calcination temperature for one-part geopolymers.

The OMPs A (OmpA)—of Edwardsiella anguillarum and OmpU of V. vulnificus have been proven to be good antigens. In this study, after construction of a vector, a new recombinant Omp (rOMP) containing both OmpA and OmpU was expressed and purified. Then, the Japanese eels (Anguilla japonica) were intraperitoneally (i.p.) injected with the phosphate‐buffered saline (PBS group), formalin‐killed‐cell (FKC group) or the recombinant Omp (rOMP group). The stimulation index of the whole blood cells in eels from FKC group was significantly higher than the eels from PBS and rOMP groups at 28 dpi; serum titers of anti‐E. anguillarum and anti‐V. vulnificus antibody of eels from FKC and rOMP group increased significantly at 21 and 28 dpi; in the rOMP group, eels serum titer stayed at a high level on 42 dpi. The activities of lysozyme in skin mucus, liver, kidney, and serum in three groups exhibited considerable changes. The relative percent survival (RPS) rate of eels from rOMP group were 100% and 83% when challenged with V. vulnificus or E. anguillarum. These results indicated that inoculation of rOMP would protect Japanese eels against the infection by E. anguillarum and V. vulnificus.

By using phthalic acid as a soft template, we showed that it was possible to prepare a microporous aluminum-based material when the precipitation of Al(3+) was properly controlled. We also identified that this microporous aluminum-based material could be promising for the removal of fluoride ions in water treatment.

A pH and redox responsive bi-trigger continuous drug release nanocarrier is developed by capping mesoporous carbon nanoparticles (MCNs) with polyacrylic acid (PAA), termed as PAA-ss-MCN. The nanocarrier contains disulfide bond units and exhibits pH responsive behavior. It provides promising potential for drug loading due to the internal uniform channels and large surface area of MCNs. PAA grafted on the exterior surface of MCNs acts as a gating layer, generating a novel nano-container and a pH-responsive intelligent nanovalve. By loading doxorubicin (DOX) in PAA-ss-MCN, its sequential release is achieved via two approaches: (1) the intracellular acidic environment induces partial release from the surface of the PAA gating layer, (2) release of the drug sealed in nanochannels via disruption of the integrity of the nanocarrier by glutathione (GSH) caused dissociation of disulfide bonds in the physiological environment. As a result, release of 62% loaded drug is readily achieved. After culturing with HeLa cells, DOX transports into the cell interior and therein exhibits pH- and GSH-sensitive release. As most tumor sites exhibit more acidic environments or high redox potential, the pH- and GSH-sensitive releasing capability of PAA-ss-MCN is particularly useful for controllable drug delivery by taking advantage of the inherent characteristics of tumor cells.

A novel pH-responsive drug delivery system, based on permeation-enhancing glutathione (GSH) and pH sensitive polyacrylic acid (PAA) grafted mesoporous organosilica nanocarriers (MONs), is developed. PAA grafted MONs are prepared via a facile grafting-to strategy and then GSH is conjugated on the PAA chain via an amidation reaction. The resultant MONs–PAA–GSH conjugate not only shows an efficient drug loading efficiency but also offers a superb binding capability to cell membranes. With doxorubicin hydrochloride (DOX) as a model, a loading efficiency of 43.7% is readily achieved for 1.0 mg mL−1 DOX in 1.0 mL aqueous medium with 1.0 mg of MONs–PAA–GSH conjugate. The ensuing release of DOX from the DOX–MONs–PAA–GSH conjugate is pH-dependent, offering release efficiencies of 70.2% (pH 3.0), 45.5% (pH 5.0) and 16.1% (pH 6.5), within 24 h. The MONs–PAA–GSH conjugate displays favorable cellular uptake properties, minimum cytotoxic effect or excellent biocompatibility in comparison with those for MONs–PAA. It is demonstrated that the MONs–PAA–GSH conjugate serves as a promising platform for building a controlled drug delivery system.

Hollow nanostructures of metal oxides have found broad applications in different fields. Here, we reported a facile and versatile synthetic protocol to prepare hollow metal oxide nanospheres by modulating the chemical properties in solid nanoparticles. Our synthesis design starts with the precipitation of urea-containing metal oxalate, which is soluble in water but exists as solid nanospheres in ethanol. A controlled particle hydrolysis is achieved through the heating-induced urea decomposition, which transforms the particle composition in an outside-to-inside style: The reaction starts from the surface and then proceeds inward to gradually form a water-insoluble shell of basic metal oxalate. Such a reaction-induced solubility difference inside nanospheres becomes highly efficient to create a hollow structure through a simple water wash process. A following high temperature treatment forms hollow nanospheres of different metal oxides with structural features suited to their applications. For example, a high performance anode for Li-ion intercalation pseudocapacitor was demonstrated with the hollow and mesoporous Nb

A polyethyleneimine (PEI)-iron phosphate (FePO4) nanocomposite is prepared by immobilization of PEI onto the surface of FePO4 nanoparticles via electrostatic interaction. The obtained PEI-FePO4 nanocomposites are spherical with a size centered in ca. 100 nm. They provide a novel adsorbent for the solid-phase extraction of DNA from complex sample matrices. At pH 4, 50 μg mL(-1) of DNA (salmon sperm DNA sodium salt) in 1.0 mL aqueous solution are quantitatively adsorbed (100%) by 2mg of the PEI-FePO4 nanocomposites, and meanwhile the coexisting albumin at a same concentration level is not retained, demonstrating the favorable selectivity of the nanocomposites to DNA against proteins. The adsorption behaviors of DNA onto the PEI-FePO4 nanocomposites fit Langmuir model, corresponding to an adsorption capacity of 61.88 mg g(-1). The adsorbed DNA could be readily recovered by using a 0.04 mol L(-1) Britton-Robinson (BR) buffer at pH 10, resulting in a recovery of 85%. The nanocomposites have been further used for the isolation of DNA from a series of real sample matrices, including synthetic λ-DNA sample, human whole blood and Escherichia coli cell lysate. The extraction efficiency and the purity of the recovered DNA are at least comparable to those achieved by using the reported sorbent materials or commercial kits. In addition, the DNAs isolated from human whole blood and E. coli cell lysate are of high quality, which have been further demonstrated by using them as templates for successful PCR amplifications.

A Keggin-type cobalt mono-substituted silicotungstic acid doped with aniline (SiW11Co–PANI composite, where PANI denotes polyaniline) is prepared by a liquid phase method at room temperature. The obtained SiW11Co–PANI composite possesses a porous framework structure and has proven to be a promising adsorbent for the retention of proteins, which exhibits favorable selectivity toward the adsorption of ovalbumin from egg whites. 5.0 mg of SiW11Co–PANI composite gives rise to an adsorption efficiency of >70% for 100 mg L−1 ovalbumin in 1.0 mL of sample solution within a wide pH range of 3–9, and a maximum adsorption efficiency of 92% is achieved at pH 9. The adsorption behavior of ovalbumin onto the SiW11Co–PANI composite fits the Langmuir adsorption model, corresponding to a sorption capacity of 200.0 mg g−1. The retained ovalbumin could be readily recovered by using a 0.1 mol L−1 phosphate buffer at pH 5.6 as a stripping reagent, providing a recovery of 84.4%. Circular dichroism (CD) spectra illustrate virtually no change in the conformation of ovalbumin after the process of adsorption–desorption. The SiW11Co–PANI composite has been applied for the selective adsorption of ovalbumin from the chicken egg white, and SDS-PAGE assay demonstrates that high purity of ovalbumin is obtained.

A multifunctional drug nanocarrier is developed by incorporating acetaldehyde-modified-cystine (AMC) into mesoporous organosilica nanoparticles (MONs), shortly termed as MONs-AMC. The anticancer drug doxorubicin (DOX) links directly to MONs-AMC through electrostatic interaction between DOX and AMC to produce a conjugate, MONs-AMC-DOX, with a drug loading efficiency of 26.24 ± 1.35%, corresponding to a loading capacity of 0.26 ± 0.01 mg mg −1 for DOX. Schiff base AMC contains a –S–S– bond and two –C˭N– bonds which cleave in the presence of certain level of GSH and in an acidic medium, providing MONs-AMC-DOX the capability for triggering pH and glutathione (GSH) dual-responsive drug release. Further, the self-fluorescent nature of AMC offers the tracing capability without the need of fluorescent label, which facilitates real-time tracing of the drug delivery and cancer therapy process. With 10 mmol L −1 GSH and at pH 5.0, a drug release efficiency of 52.27 ± 2.84% is achieved. The intracellular drug release process is traced with confocal laser scanning microscope by monitoring the green fluorescence of MONs-AMC-DOX and red fluorescence of DOX with excitation at 408 nm and 488 nm, respectively. The drug loaded nanocarriers exhibit a time-dependent cellular uptake behavior, providing an enhanced therapeutic effect to A549 cancer cells.

Carbon dots (C-dots) have been proven to show the capability for direct reduction of Ag(+) to elemental silver (Ag(0)) without additional reducing agent or external photoirradiation by incubating Ag(+) with C-dots for 5 min in a water bath at 50 °C. Silver nanoparticles (Ag-NPs) are simultaneously formed with an average size of 3.1 ± 1.5 nm and grew on carbon dots. This process involves the oxidation of amine or phenol hydroxyl groups on the aromatic ring of C-dots. Meanwhile C-dots protect and stabilize the Ag-NPs from aggregation in aqueous medium; that is, the Ag-NPs are stable at least for 45 days in aqueous medium. The formed Ag-NPs cause significant resonance light scattering (RLS), which correlates closely with the concentration of silver cation, and this facilitates quantitative detection of silver in aqueous medium.

The detection of mercury in biological systems and its imaging is of highly importance. In this work, a ratiometric fluorescence sensor is developed based on fluorescence resonance energy transfer (FRET) with N-acetyl-L-cysteine functionalized quantum dots (NAC-QDs) as donor and Rhodamine 6G derivative-mercury conjugate (R6G-D-Hg) as acceptor. Mercury annihilates the fluorescence of NAC-QDs at 508 nm and meanwhile interacts with R6G derivative to form a fluorescent conjugate giving rise to emission at 554 nm. Resonance energy transfer from NAC-QDs to R6G-D-Hg is triggered by mercury resulting in concentration-dependent variation of fluorescence ratio F508/F554. A linear calibration of F508/F554 versus mercury concentration is obtained within 5-250 μg L(-1), along with a detection limit of 0.75 μg L(-1) and a RSD of 3.2% (175 μg L(-1)). The sensor generates colorimetric images for mercury within 0-250 μg L(-1), facilitating visual detection of mercury with a distinguishing ability of 50 μg L(-1). This feature is further demonstrated by colorimetric imaging of intracellular mercury. On the other hand, the NAC-QDs/R6G-D FRET sensing system is characterized by a combination of high sensitivity and selectivity. The present study provides an approach for further development of ratiometric sensors dedicated to selective in vitro or in vivo sensing some species of biologically interest.

China produces the greatest amount of propolis but there is still lack of basic studies on its pharmacological mechanisms. Our previous study found that ethanol extract from Chinese propolis (EECP) exerted excellent anti-inflammatory effectsin vivobut mechanisms of action were elusive. To further clarify the possible mechanisms underlying the anti-inflammatory effects of Chinese propolis (poplar type), we utilized EECP to analyze its chemical composition and evaluated its potential anti-inflammatory effectsin vitro. High-performance liquid chromatography (HPLC) profile indicated that EECP contained abundant flavonoids, including rutin, myricetin, quercetin, kaempferol, apigenin, pinocembrin, chrysin, and galangin. Next we found that EECP could significantly inhibit the production of NO, IL-1β, and IL-6 in lipopolysaccharide- (LPS-) stimulated RAW 264.7 cells and suppress mRNA expression of iNOS, IL-1β, and IL-6 in a time- and dose-dependent manner. Furthermore, we found that EECP could suppress the phosphorylation of IκBαand AP-1 but did not affect IκBα’s degradation. In addition, using a reporter assay, we found that EECP could block the activation of NF-κB in TNF-α-stimulated HEK 293T cells. Our findings give new insights for understanding the mechanisms involved in the anti-inflammatory effects by Chinese propolis and provide additional references for using propolis in alternative and complementary therapies.

The specific and non-specific immune parameters and protection of American eels (Anguilla rostrata) were evaluated after immunized eels with a bivalent expressed out membrane protein (OMP) of porin Ⅱ of Aeromonas hydrophila and ompS2 of Edwardsiella tarda. One hundred eighty eels were distributed into 3 equal groups and intraperitoneal (i.p) injection with phosphate-buffered saline (PBS group), formalin-killed-whole-cell (FKC) of A. hydrophila and E. tarda (FKC group) or the bivalent OMP (OMP group). The lymphocytes and red blood cells collected on 14, 21 and 42 days post-vaccination were used to evaluate the stimulation index (SI) and the sera collected on 14, 21, 28 and 42 days were used to assize the titers of specific antibody as well as lysozyme activity. Lysozyme activities in skin mucus, suspension of liver and kidney were also recorded on 14, 21 and 28 days. On 28 d post-vaccination, eels from all three groups were challenged by i.p injection of live A. hydrophila or E. tarda. The results show that, compared with the PBS group, proliferation of lymphocytes in OMP group was significantly (P < 0.05) enhanced on 21 days, and the serum titers of anti-A. hydrophila and anti- E. tarda antibody in eels of FKC and OMP group were significant increased (P < 0.05 or P < 0.01) on 14, 21 and 28 days. Activity of the lysozyme in serum, skin mucus, liver and kidney were significant changed (P < 0.05 or P < 0.01) between the three groups. Relative Percent Survival (RPS) after challenged with A. hydrophila on 28 days post immunization in two vaccinated groups vs. PBS group were 50%, and the RPS challenge E. tarda in FKC and OMP vs. PBS group were 50% and 37.5% respectively. These results suggest that American eels immunized with the bivalent OMP would positively affect specific as well as non-specific immune parameters and protect against infection by the two pathogens in freshwater farming.