Bioactive compounds from Physalis angulata and their anti-inflammatory and cytotoxic activities.

A new compound, physalucoside A (1), together with seven withanolides (2-8) and three flavonoids (9-11), were isolated from Physalis angulata L. (Solanaceae), a medicinal plant native to Vietnam. The chemical structures of these compounds were elucidated by one- and two-dimensional NMR spectra, high-resolution electrospray ionization mass spectrometry analyses, and chemical reactivity. The anti-inflammatory and cytotoxic activities of isolated compounds were also evaluated. These data suggest that the anti-inflammatory activity of P. angulata is due primarily to its withanolide content. This study demonstrates the potential of withanolides as promising candidates for the development of new anti-inflammatory drugs.

PEGylated PAMAM dendrimers loading oxaliplatin with prolonged release and high payload without burst effect.

Oxaliplatin (OXA) was coupled to PEGylated polyamidoamine dendrimers of fourth generation (G4-PEG@OXA) in the comparison to PEGylated ones of odd generation (G3.5-PEG@OXA). Proton nuclear magnetic resonance and Fourier-transform infrared spectroscopy were used to confirm the successful incorporation of OXA as well as the synthesis of carrier systems. Both two types of carrier systems exhibited in sphere nanoparticle shape with size of less than 100 nm that was in the range being able to cause toxicity on cancer cells. The average drug loading efficiency (DLE) of G4-PEG@OXA was obtained at 84.63% that was higher than DLE of G3.5-PEG of 75.69%. The release kinetic of G4-PEG@OXA and G3.5-PEG@OXA did not show any burst release phenomenon while free OXA was released over 40% at the first hour. The sustainable release of OXA was achieved when it was encapsulated in these carriers, but the G4 generation liberated OXA (3.4%-6.4%) slower than G3.5 one (11.9%-22.8%). The in vitro cytotoxicities of G4-PEG@OXA were evaluated in HeLa cell lines using resazurin assay and live/dead staining test. Although the free OXA showed a rather moderate killing ability, the G4-PEG@OXA still displayed the low viability of HeLa that was better to the result of G3.5-PEG@OXA due to released OXA amount. The benefit of this system was to overcome the burst release phenomenon to minimize OXA toxicity without compromising its efficiency.

Efficient Method for Preparation of Rutin Nanosuspension Using Chitosan and Sodium Tripolyphosphate Crosslinker.

High concentration of rutin nanosuspension (5%) in water was prepared by using high-speed and high-pressure homogenizer. Sodium tripolyphosphate (STPP) crosslinker and chitosan polymer were found to be an efficient encapsulating reagent and stabilizer to prepare rutin nanosuspension. In addition, the particle sizes and sedimentation rates of rutin nanosuspension were investigated under effects of several factors, including applied pressures of homogenization, the presence of co-solvent PEG 400 (polyethylene glycol 400), chitosan loading, STPP and chitosan mass ratio. Raw rutin material was characterized using powder X-ray diffraction (XRD) and high-performance liquid chromatography (HPLC). To evaluate the parameter of rutin nanosuspension, laser diffraction spectrometry (LDS) was employed to estimate the particle size distribution. Rutin nanosuspension prepared under optimal conditions was freezing dried/spray dried to form rutin powders. Properties of the rutin powders were evaluated using XRD analysis and re-dispersion into aqueous solutions of different pH values.

Photoluminescence Properties of Eu-Doped MIL-53(Fe) Obtained by Solvothermal Synthesis.

We report the facial synthesis of Eu-doped MIL-53(Fe) elongated hexagonal dipyramid by solvothermal reaction of Fe(NO3)3, Eu(NO3)3 and terephthalic acid (TPA) in the presence of N,N-dimethylformamide (DMF). The as-synthesized samples were characterized by XRD, Raman, FT-IR, PL, and SEM. From XRD and Raman results, metal replacement (Eu) with the metal ion (Fe) in the crystal lattice may change the high crystallinity of the MIL-53(Fe) structure, and all the metal ions were incorporated into the structures of MIL-53(Fe) as well as replaced Fe ion or located at interstitial site. From PL result, Eu-doped MIL-53(Fe) showed unique Eu fluorescence properties with high emission intensity, thus enabling it to be a promising functional probe for fluorescent imaging.

High Conductivity and Surface Area of Mesoporous Ti0.7W0.3O2 Materials as Promising Catalyst Support for Pt in Proton-Exchange Membrane Fuel Cells.

In this work, mesoporous Ti0.7W0.3O2 materials with high conductivity and surface area as promising catalyst support for Pt in Proton-Exchange Membrane Fuel Cells (PEMFCs) were synthesized via a single-step solvothermal process at low-temperature without using any surfactants or stabilizers. The characterizations of material are measured via XRD, TEM, SEM-EDS, and BET as well as electronic conductivity measurement. As a result, Ti0.7W0.3O2 formed a homogenous solid solution with mesoporous anatase-TiO2 structure and uniformly spherical nanoparticles morphology of about ~10 nm diameter, together with a high electrical conductivity of 0.022 S/cm compared to that of undoped-TiO2 (1.37×10-7 S/cm), which implied that tungsten (VI) ions was successfully doped into anatase-TiO2 lattices. The N2 adsorption/desorption isotherms indicated that Ti0.7W0.3O2 is being mesoporous structure with high surface area up to ~202 m²/g, which is nearly similar to that of the commercial Vulcan XC72 (~232 m²/g). The Pt nanoparticles was easily anchored onto Ti0.7W0.3O2 surface by the chemical reduction process using NaBH4 as a reducing agent. The spherical Pt nanoparticles of ~9 nm in diameter were deposited uniformly on the mesoporous support. These results suggested that mesoporous Ti0.7W0.3O2 materials synthesized are promising catalyst supports to replace carbon-based supports for Proton-exchange membrane fuel cells.

Grafting of Poly(poly(ethylene glycol) methacrylate) onto Halloysite Nanotubes via Surface-Initiated Atom Transfer Radical Polymerization.

A synthetic strategy for the functionalization of halloysite nanotubes (HNTs) with poly(poly(ethylene glycol) methacrylate) (PPEGMA) via surface-initiated atom transfer radical polymerization (SIATRP). The covalent immobilization of PPEGMA was confirmed by FT-IR analysis. The preparation of the nanohybrids was further evidenced by the XPS and EDX studies. The morphologies of functionalized HNTs were investigated by FE-SEM analysis. TGA results suggested that the nanohybrids can be used in high temperature applications. Thus, this newly developed surface functionalization protocol offers the tailoring of the HNTs surface with wide functionalities and is potentially useful to the biomedical applications.

Glutathione Capped CdSe Quantum Dots: Synthesis, Characterization, Morphology, and Application as a Sensor for Toxic Metal Ions.

Glutathione (GSH) functionalized CdSe quantum dots (QDs) (GSH-f-CdSe QDs) were prepared via a simple one-pot strategy at low temperature. The as-synthesized CdSe QDs were characterized by FT-IR and XPS analyses. The morphology, physical structure and size distribution of GSH-f-CdSe QDs were investigated by TEM, XRD and DLS analyses, respectively. The GSH-f-CdSe QDs exhibited excellent stability of optical properties as investigated by UV-Vis absorption and photoluminescence (PL) spectroscopy. The high affinity of GSH towards heavy metal ions made the GSH-f-CdSe QDs quite susceptible to Pb2+ ion which poses serious threat to the health and environment. The PL intensity of GSH-f-CdSe QDs was observed to be apparently quenched in the presence of Pb2+ ions in aqueous solution rendering their potentialities as a sensor for detection of toxic heavy metal ions.

The Preparation and Characterization of Expanded Graphite via Microwave Irradiation and Conventional Heating for the Purification of Oil Contaminated Water.

Recently, the graphite based materials have gained interest as excellent platforms to remove aqueous pollutants via adsorption routes. This is given that such materials possess large specific surface area and low density. In the present work, a comparative study of two facile and effective approaches is conventional thermal heating and microwave irradiation methods to fabricate expanded graphite from available flake graphite sources of Vietnam for oil-contaminated water purification. The as-prepared expanded graphite was characterized by using FT-IR, SEM, XRD and BET analysis. The results exhibited that expanded graphite has multilevel pore structures and the surface area of expanded graphite obtained from microwave irradiation and conventional heating was 147.5 (m²/g) and 100.97 (m²/g) under optimal processing conditions. The as-synthesized expanded graphite from the microwave irradiation method was found to have higher adsorption capacities for diesel oil, crude oil, and fuel oil compared to conventional heating method.

Modified Carboxyl-Terminated PAMAM Dendrimers as Great Cytocompatible Nano-Based Drug Delivery System.

Polyamidoamine (PAMAM) dendrimers are extensively researched as potential drug delivery system thanks to their desirable features such as controlled and stable structures, and ease of functionalization onto their surface active groups. However, there have been concerns about the toxicity of full generation dendrimers and risks of premature clearance from circulation, along with other physical drawbacks presented in previous formulations, including large particle sizes and low drug loading efficiency. In our study, carboxyl-terminated PAMAM dendrimer G3.5 was grafted with poly (ethylene glycol) methyl ether (mPEG) to be employed as a nano-based drug delivery system with great cytocompatibility for the delivery of carboplatin (CPT), a widely prescribed anticancer drug with strong side effects so that the drug will be effectively entrapped and not exhibit uncontrolled outflow from the open structure of unmodified PAMAM G3.5. The particles formed were spherical in shape and had the optimal size range (around 36 nm) that accommodates high drug entrapment efficiency. Surface charge was also determined to be almost neutral and the system was cytocompatible. In vitro release patterns over 24 h showed a prolonged CPT release compared to free drug, which correlated to the cytotoxicity assay on malignant cell lines showing the lack of anticancer effect of CPT/mPEG-G3.5 compared with CPT.

Fatty Acid, Lipid Classes and Phospholipid Molecular Species Composition of the Marine Clam Meretrix lyrata (Sowerby 1851) from Cua Lo Beach, Nghe An Province, Vietnam.

This study aims to analyze compositions of fatty acids and phospholipid molecular species in the hard clams Meretrix lyrata (Sowerby, 1851) harvested from Cua Lo beach, Nghe An province, Viet Nam. Total lipid of hard clams Meretrix lyrata occupied 1.7 ± 0.2% of wet weight and contained six classes: hydrocarbon and wax (HW), triacylglycerol (TAG), free fatty acids (FFA), sterol (ST), polar lipid (PoL), and monoalkyl diacylglycerol (MADAG). Among the constituents, the proportion of PoL accounted was highest, at 45.7%. In contrast, the figures for MADAG were lowest, at 1.3%. Twenty-six fatty acids were identified with the ratios of USAFA/SAFA was 2. The percentage of n-3 PUFA (ω-3) and n-6 PUFA (ω-6) was high, occupying 38.4% of total FA. Among PUFAs, arachidonic acid (AA, 20:4n-6), eicosapentaenoic acid (EPA, 20:5n-3), docosapentaenoic acid (DPA, 22:5n-3), and docosahexaenoic acid (DHA, 22:6n-3) accounted for 3.8%, 7.8%, 2.2% and 12.0% of total lipid of the clam respectively. Phospholipid molecular species were identified in polar lipids of the clams consisting six types: phosphatidylethalnolamine (PE, with 28 molecular species), phosphatidylcholine (PC, with 26 molecular species), phosphatidylserine (PS, with 18 molecular species), phosphatidylinositol (PI, with 10 molecular species), phosphatidylglycerol (PG, with only one molecular species), and ceramide aminoethylphosphonate (CAEP, with 15 molecular species). This is the first time that the molecular species of sphingophospholipid were determined, in Meretrix lyrata in particular, and for clams in general. Phospholipid formula species of PE and PS were revealed to comprise two kinds: Alkenyl acyl glycerophosphoethanolamine and Alkenyl acyl glycerophosphoserine occupy 80.3% and 81.0% of total PE and PS species, respectively. In contrast, the percentage of diacyl glycero phosphatidylcholine was twice as high as that of PakCho in total PC, at 69.3, in comparison with 30.7%. In addition, phospholipid formula species of PI and PG comprised only diacyl glycoro phospholipids. PE 36:1 (p18:0/18:1), PC 38:6 (16:0/22:6), PS 38:1 (p18:0/20:1), PI 40:5 (20:1/20:4), PG 32:0 (16:0/16:0) and CAEP 34:2 (16:2/d18:0) were the major molecular species.

Combined Minimum-Run Resolution IV and Central Composite Design for Optimized Removal of the Tetracycline Drug Over Metal⁻Organic Framework-Templated Porous Carbon.

In this study, a minimum-run resolution IV and central composite design have been developed to optimize tetracycline removal efficiency over mesoporous carbon derived from the metal-organic framework MIL-53 (Fe) as a self-sacrificial template. Firstly, minimum-run resolution IV, powered by the Design-Expert program, was used as an efficient and reliable screening study for investigating a set of seven factors, these were: tetracycline concentration (A: 5-15 mg/g), dose of mesoporous carbons (MPC) (B: 0.05-0.15 g/L), initial pH level (C: 2-10), contact time (D: 1-3 h), temperature (E: 20-40 °C), shaking speed (F: 150-250 rpm), and Na+ ionic strength (G: 10-90 mM) at both low (-1) and high (+1) levels, for investigation of the data ranges. The 20-trial model was analyzed and assessed by Analysis of Variance (ANOVA) data, and diagnostic plots (e.g., the Pareto chart, and half-normal and normal probability plots). Based on minimum-run resolution IV, three factors, including tetracycline concentration (A), dose of MPC (B), and initial pH (C), were selected to carry out the optimization study using a central composite design. The proposed quadratic model was found to be statistically significant at the 95% confidence level due to a low P-value (<0.05), high R2 (0.9078), and the AP ratio (11.4), along with an abundance of diagnostic plots (3D response surfaces, Cook's distance, Box-Cox, DFFITS, Leverage versus run, residuals versus runs, and actual versus predicted). Under response surface methodology-optimized conditions (e.g., tetracycline concentration of 1.9 mg/g, MPC dose of 0.15 g/L, and pH level of 3.9), the highest tetracycline removal efficiency via confirmation tests reached up to 98.0%-99.7%. Also, kinetic intraparticle diffusion and isotherm models were systematically studied to interpret how tetracycline molecules were absorbed on an MPC structure. In particular, the adsorption mechanisms including "electrostatic attraction" and "π-π interaction" were proposed.

Core-Shell Fe@SiO2 Nanoparticles Synthesized via Modified Stober Method for High Activity in Cr(VI) Reduction.

In this paper, Fe@SiO2 nanoparticles (α-Fe nanoparticles coated with SiO2 shell) were synthesized at room temperature using the modified Stöber method combined with potassium borohydride (KBH4) reduction process. The present study depicts the facile synthesis of Fe@SiO2 without the presence of surfactants and stabilizers. In this experiment, KBH4 acted both as a reducing agent for iron salt and a catalyst for hydrolysis and polycondensation of tetraethylorthosilicate (TEOS). The Fe@SiO2 nanoparticles were characterized using X-ray diffraction method, specific surface area (BET) technique, transmission electron microscope (TEM), and vibrating sample magnetometer (VSM). The optimal mass ratio of Fe in the form of anhydrous ferric chloride (FeCl3) and SiO2) in the form of TEOS was 4:1. α-Fe-Fe nanoparticles (size of about 45 nm) were coated with approximately 10 nm thick SiO2 shells. Moreover, Fe/SiO2 (Fe0 nanoparticles supported by silica nanoparticles) was synthesized to compare the results. Due to the silica shells, Fe cores cannot be oxidized when dipped in the concentrated sulfuric acid, and hence, the removal of Cr(VI) was not weakened in the acidic environment.

One-Step Hydrothermal Synthesis of a New Nanostructure Ti07Ir03O2 for Enhanced Electrical Conductivity: The Effect of pH on the Formation of Nanostructure.

Non-carbon materials are considered as the promising candidates for carbon-based catalyst support to increase the durability of proton exchange membrane fuel cells (PEMFCs). Due to the high stability and good electrical conductivity of TiO2, M-doped TiO2 (M is transition metals: Mo, Ru, V, W) is an emerging candidate for Pt nanoparticles support on the cathode side of PEMFCs. In this research, the synthesis mechanism of Ti0.7Ir0.3O2 nanostructure by the one-step hydrothermal method at low temperature was studied. We found that by only controlling the pH of the precursor solution, Ti0.7Ir0.3O2 can be synthesized with different morphology and phase selection without any formation of mixed oxides. In particular, Ti0.7Ir0.3O2 nanostructure synthesized at pH = 0 exhibited concomitant anatase, brookite, and rutile phases. The spherical particles of diameter 20-40 nm, cubic particles of 30-50 nm in side-length and rod-like particles with 70 nm in length and 20 nm in diameter represented the anatase, brookite, and rutile phases respectively. At a pH value of 1 or 2, the majority of spherical nanoparticles were homogeneous at 15-20 nm in diameter. It was observed that the electronic conductivity of novel Ti0.7Ir0.3O2 nanostructure was significantly higher than that of the undoped TiO2. Thus the promising properties of this new nanostructure open a new path to the much-needed fuel cell applications.

Nanostructured Ti07Mo03O2 as Efficient Non-Carbon Support for PtRu Catalysts in Direct Methanol Fuel Cells.

This study was focused on a new strategy by investigating whether the novel Ti0.7Mo0.3O2 material can be used as a conductive support for PtRu to prevent carbon corrosion and improve catalyst activity as the novel Ti0.7Mo0.3O2 support has some functional advantages. The 30 wt% PtRu/Ti0.7Mo0.3O2 catalyst showed the highest current density at the complete potential, which is approximately 12-fold and 1.4-fold higher than that of the commercial 20 wt% Pt/C (E-TEK) and 30 wt% PtRu/C (JM) catalysts, respectively, at 0.6 V (NHE) toward the methanol oxidation (MOR). Our data suggest that this enhancement is a result of the electronic Pt structure change upon its synergistic interaction with Ti0.7Mo0.3O2 support and the improved mass transport kinetics of PtRu/Ti0.7Mo0.3O2 compared to the carbon support (Pt or PtRu). The PtRu/Ti0.7Mo0.3O2 catalyst exhibited a much higher stability than carbon-supported catalysts because of the strong metal/support interactions between the Pt particles and Ti0.7Mo0.3O2, the inherent structural and chemical stability, and the corrosion resistance of the Ti0.7Mo0.3O2 in acidic and oxidative environments.

Advanced Ti0.7W0.3O2 Nanoparticles Prepared via Solvothermal Process Using Titanium Tetrachloride and Tungsten Hexachloride as Precursors.

The degradation of Pt-based catalysts is considered as the main barrier to the commercialization of fuel cells. M-doped TiO2 (M is a transition metal) has been investigated to improve the stability of electrocatalysts. Recently, W-doped TiO2 materials have been found as a good catalyst support for the photocatalyst applications but their application in Proton-exchange membrane fuel cell application has rarely been reported. In addition, the agglomeration of nanoparticles, which are synthesized from the organic precursor, has been reported. Here, we report Ti0.7W0.3O2 nanoparticles prepared via a one-step solvothermal method with inorganic precursors without using surfactants or stabilizers for restricting nanoparticle agglomeration. The properties of the material were measured by XRD, TEM, BET, and electronic conductivity. The mean particle size of ∼5 nm, the high specific surface area of 126.471 m2/g and a moderate electronic conductivity of 0.014 S/cm were obtained for the sample prepared at 220 °C for 4 h. It was observed that using inorganic precursors to prevent particle agglomeration is more advantageous compared to organic precursors as mentioned in previous reports.

Synthesis and Characterization of Advanced Nanomaterials: Tin-Doped Indium Oxide (ITO) and Platinium Deposited on Tin-Doped Indium Oxide (Pt/ITO).

This article describes the synthesis and characterization of tin-doped indium oxide (ITO) and platinum nanoparticles deposited on ITO. For different calcination temperatures, the tin-doped indium oxide nanoparticles (ITO NPs) were synthesized successfully by a nonaqueous sol-gel method with indium acetylacetonate and tin bis(acetylacetonate) dichloride in oleylamine as the precursors. The ITO sample that calcinated at 500 °C exhibited a spherical morphology with a narrow range of the particle size distribution (15-20 nm). Moreover, the electrical conductivity of the sample (1.242 S/cm) was higher than many different non-carbon supports. In addition, 20% platinum nanoparticles (Pt NPs) were also deposited uniformly on the ITO supports via chemical reduction process using NaBH4 as the reducing agent. The size of Pt NPs was about 5 nm and the crystalline structure of ITO supports remained unchanged.

The Suppressive Activity of Fucofuroeckol-A Derived from Brown Algal Ecklonia stolonifera Okamura on UVB-Induced Mast Cell Degranulation.

UV light, especially UVB, is known as a trigger of allergic reaction, leading to mast cell degranulation and histamine release. In this study, phlorotannin Fucofuroeckol-A (F-A) derived from brown algal Ecklonia stolonifera Okamura was evaluated for its protective capability against UVB-induced allergic reaction in RBL-2H3 mast cells. It was revealed that F-A significantly suppress mast cell degranulation via decreasing histamine release as well as intracellular Ca2+ elevation at the concentration of 50 µM. Moreover, the inhibitory effect of F-A on IL-1ß and TNF-α productions was also evidenced. Notably, the protective activity of F-A against mast cell degranulation was found due to scavenging ROS production. Accordingly, F-A from brown algal E. stolonifera was suggested to be promising candidate for its protective capability against UVB-induced allergic reaction.

Synergic Activity Against MCF-7 Breast Cancer Cell Growth of Nanocurcumin-Encapsulated and Cisplatin-Complexed Nanogels.

Nanogel-based systems loaded with single anticancer drugs display miscellaneous effectiveness in tumor remission, gradually circumventing mutation and resistance in chemotherapy. Hence, the existence of dual-drug delivered nano-sized systems has been contemporaneous with drug development and preceded the conventional-dose chemotherapy. Among outstanding synergistic drug nanoplatforms, thermosensitive copolymer heparin-Pluronic F127 (Hep-F127) co-delivering cisplatin (CDDP) and curcumins (Cur) (Hep-F127/CDDP/Cur) has emerged as a notable candidate for temperature-responsive drug delivery. The procedure was based on the entrapment of curcumin into the hydrophobic core of bio-degradable co-polymer Hep-F127 while the hydrophilic drug CDDP subsequently conjugated to the backbone heparin to form the core-shell structure. The copolymer was characterized by Fourier transform infrared (FT-IR) spectrophotometry, Transmission Electron Microscopy (TEM), and Dynamic Light Scattering (DLS), to corroborate the successful synthesis and via HPLC along with AES-ICP to evaluate the high drug loading along with a controllable release from the nano-gels. A well-defined nano-shell with size in the 129.3 ± 3.8 nm size range could enhance higher the efficacy of the conjugated-CDDP to Hep-F127 than that of single doses. Moreover, the considerable amount of dual-drug released from thermosensitive nanogels between different conditions (pH = 7.4 and pH = 5.5) in comparison to CDDP from Hep-F127 partially indicated the significantly anti-proliferative ability of Hep-F127/CDDP/Cur to the MCF-7 cell line. Remarkably, drug testing in a xenograft model elucidates the intricate synergism of co-delivery in suppressing tumor growth, which remedies some of the problems affecting in cancer chemotherapy.

Application of response surface methodology to optimize the fabrication of ZnCl2-activated carbon from sugarcane bagasse for the removal of Cu2.

The present study focused on the application of response surface methodology to optimize the fabrication of activated carbon (AC) from sugarcane bagasse for adsorption of Cu2+ ion. The AC was synthesized via chemical activation with ZnCl2 as the activating agent. The central composite design based experiments were performed to assess the individual and interactive effect of influential parameters, including activation temperature, ZnCl2 impregnation ratio and activation time on the AC yield and removal of Cu2+ ion from the aqueous environment. The statistically significant, well-fitting quadratic regression models were successfully developed as confirmed by high F- and low P-values (<0.0001), high correlation coefficients and lack-of-fit tests. Accordingly, the optimum AC yield and removal efficiency of Cu2+ were predicted, respectively, as 48.8% and 92.7% which were approximate to the actual values. By applying the predicted optimal parameters, the AC shows a surprisingly high surface area of around 1,500 m2/g accompanied by large pore volume and narrow micropore size at low fabrication temperature.