Lentinan-functionalized selenium nanoparticles induce apoptosis and cell cycle arrest in human colon carcinoma HCT-116 cells.

Selenium nanoparticles (SeNPs) have gained extensive attention for their excellent biological activity and low toxicity. However, SeNPs are extremely liable to aggregate into non-bioactive or gray elemental selenium, which limits their application in the biomedicine field. This study aimed to prepare stable SeNPs by using lentinan (LNT) as a template and evaluate its anti-colon cancer activity. The average particle diameter of obtained lentinan-selenium nanoparticles (LNT-SeNPs) was approximately 59 nm and presented zero-valent, amorphous, and spherical structures. The monodisperse SeNPs were stabilized by LNT through hydrogen bonding interactions. LNT-SeNPs solution remained highly stable at 4°C for at least 8 weeks. The stability of LNT-SeNPs solution sharply decreased under high temperature and strong acidic conditions. LNT-SeNPs showed no obvious cytotoxic effect on normal cells (IEC-6) but significantly inhibited the proliferation of five colon cancer cells (HCT-116, HT-29, Caco-2, SW620, and CT26). Among them, LNT-SeNPs exhibited the highest sensitivity toward HCT-116 cells with an IC50 value of 7.65 µM. Also, LNT-SeNPs displayed better cancer cell selectivity than sodium selenite and selenomethionine. Moreover, LNT-SeNPs promoted apoptosis of HCT-116 cells through activating mitochondria-mediated apoptotic pathway. Meanwhile, LNT-SeNPs induced cell cycle arrest at G0/G1 phase in HCT-116 cells via modulation of cell cycle regulatory proteins. The results of this study indicated that LNT-SeNPs possessed strong potential application in the treatment of colorectal cancer (CRC).

Removal of the Homolog Tellurium of Polonium by SiO2 Nanofiber Filter for Lead Alloy-Cooled Reactors.

The lead-bismuth eutectic (LBE) can be easily activated by neutron radiation to produce the radionuclide 210Po. It is therefore necessary to establish an effective method to remove vaporized polonium in the cover gas to prevent its release into the air in scenarios of reactor maintenance and coolant leakage accidents. This paper presents a SiO2 nanofiber membrane prepared based on the electrostatic spinning and calcination process. The SiO2 nanofiber membrane had the advantages of good flexibility, high-temperature resistance, and corrosion resistance. In the trapping experiments, the SiO2 nanofiber membrane filters showed excellent filtration performance at 300~400 °C, and the filtration efficiencies for Te, Pb, and Bi could reach 99%, 99%, and 98%, respectively. Proper filtration temperature and gas flow rate are important to maintain high filtration efficiency. After five cycles, the SiO2 nanofiber membrane filter still exhibited excellent cycle-use performance. In the density functional theory (DFT) calculations, PbPo and PbTe had strong interactions with amorphous SiO2, having adhesion energies of -2.96 to -2.83 eV/molecule.

Layered ammonium vanadate nanobelt as efficient adsorbents for removal of Sr2+ and Cs+ from contaminated water.

In this study, a layered ammonium vanadate (NH4V4O10) nanobelt adsorbent was synthesized by a facile hydrothermal method to remove Sr2+ and Cs+ from contaminated water. The NH4V4O10 nanobelt was texturally and morphologically characterized by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman, thermogravimetric differential thermal analyzer (TG-DSC), Brunauer- Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS) both before and after adsorbing Sr2+ and Cs+. The results showed that the NH4V4O10 nanobelt exhibited the optimal morphological structure with a 2:1 ratio of NH4VO3:dipropylamine. In the lattice of the adsorbent, the horizontal distance between oxygen atoms was 0.55 nm, the vertical distance between vanadium was 0.35 nm, and the layer distance of the adsorbent was 0.931 nm. The structure characterization indicated the VO6 octahedron formed a basic framework through sharing connected vertices. Adsorption mechanism studies indicated that ion exchange was the main adsorption mechanism for removing Sr2+ and Cs+. Batch experiments revealed that the adsorption capacity for Sr2+ was 192.52 mg/g under a pH of 2. Similarly, the adsorption capacity for Cs+ was 251.09 mg/g when the pH was 5. The adsorption kinetics and adsorption isotherms data were in accordance with the pseudo-second-order kinetic model and Langmuir model, respectively. Adsorption isotherms results also indicated that the adsorption of Sr2+ and Cs+ was endothermic (ΔHSr0 = 3.6 kJ/mol, ΔHCs0 = 29.1 kJ/mol) and increased entropy (ΔSSr0 = 29.15 J/molK, ΔSCs0 = 160.38 J/molK). Finally, the structure of the adsorbent, the adsorption performance and mechanism, and the interpretation of selective adsorption were also calculated by DFT method at the molecular level and the results were consistent with the experimental data.

Removal of V(V) From Solution Using a Silica-Supported Primary Amine Resin: Batch Studies, Experimental Analysis, and Mathematical Modeling.

Every year, a large quantity of vanadium-containing wastewater is discharged from industrial factories, resulting in severe environmental problems. In particular, V(V) is recognized as a potentially hazardous contaminant due to its high mobility and toxicity, and it has received considerable attention. In this study, a silica-supported primary amine resin (SiPAR) was prepared by in-situ polymerization, and the V(V) adsorption from the solution was examined. The as-prepared resin exhibited fast adsorption kinetics, and it could attain an equilibrium within 90 min for the V(V) solution concentration of 100 mg/L at an optimum pH of 4, whereas the commercial D302 resin required a treatment time of more than 3 h under the same conditions. Furthermore, the maximum adsorption capacity of the resin under optimum conditions for V(V) was calculated to be 70.57 mg/g. In addition, the kinetics and isotherm data were satisfactorily elucidated with the pseudo-second-order kinetics and Redlich-Peterson models, respectively. The silica-based resin exhibited an excellent selectivity for V(V), and the removal efficiency exceeded 97% in the presence of competitive anions at 100 mmol/L concentrations. The film mass-transfer coefficient (kf) and V(V) pore diffusivity (Dp) onto the resins were estimated by mathematical modeling. In summary, this study provided a potential adsorbent for the efficient removal of V(V) from wastewater.

Simultaneous Conversion of C5 and C6 Sugars into Methyl Levulinate with the Addition of 1,3,5-Trioxane.

The simultaneous conversion of C5 and C6 mixed sugars into methyl levulinate (MLE) has emerged as a versatile strategy to eliminate costly separation steps. However, the traditional upgrading of C5 sugars into MLE is very complex as it requires both acid-catalyzed and hydrogenation processes. This study concerns the development of a one-pot, hydrogenation-free conversion of C5 sugars into MLE over different acid catalysts at near-critical methanol conditions with the help of 1,3,5-trioxane. For the conversion of C5 sugars over zeolites without the addition of 1,3,5-trioxane, the MLE yield is quite low, owing to low hydrogenation activity. The addition of 1,3,5-trioxane significantly boosts the MLE yield by providing an alternative conversion pathway that does not include the hydrogenation step. A direct comparison of the catalytic performance of five different zeolites reveals that Hß zeolite, which has high densities of both Lewis and Brønsted acid sites, affords the highest MLE yield. With the addition of 1,3,5-trioxane, the hydroxymethylation of furfural derivative and formaldehyde is a key step. Notably, the simultaneous conversion of C5 and C6 sugars catalyzed by Hß zeolite can attain an MLE yield as high as 50.4 % when the reaction conditions are fully optimized. Moreover, the Hß zeolite catalyst can be reused at least five times without significant change in performance.