Well-dispersed M@TiO 2 (M = Ag, Pd, Au, Pt) nanocomposite particles with a diameter of 200-400 nm can be synthesized on a large scale by a clean photochemical route which does not require any additives using spherical rutile nanoparticles as a support. The sizes of Pt, Au, and Pd nanoparticles formed on the surface of TiO 2 particles are about 1 nm, 5 nm, and 5 nm, respectively, and the diameter of Ag nanoparticles is in the range 2-20 nm. Moreover, the noble metal nanoparticles have good dispersity on the particles of the TiO 2 support, resulting in excellent catalytic activities. Complete conversion in catalytic CO oxidation is reached at temperatures as low as 333 and 363 K, respectively, for Pt@TiO 2 and Pd@TiO 2 catalysts. In addition, the antibacterial effects of the as-synthesized TiO 2 nanoparticles, silver nanoparticles, and Au@TiO 2 and Ag@TiO 2 nanocomposites have been tested against Gram-negative Escherichia coli (E. coli) bacteria. The results demonstrate that the presence of the TiO 2 matrix enhances the antibacterial effect of silver nanoparticles, and the growth of E. coli can be completely inhibited even if the concentration of Ag in Ag@TiO 2 nanocomposite is very low (10 μg/mL).

Many potential health benefits of raspberry (Rubus idaeus L.) leaves were attributed to polyphenolic compounds, especially flavonoids. In this study, the methanol extract of R. idaeus leaves showed significant protein tyrosine phosphatase-1B (PTP1B) inhibitory activity with IC50 value of 3.41 ± 0.01 µg mL(-1) Meanwhile, a rapid and reliable method, employed high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry, was established for structure identification of flavonoids from PTP1B inhibitive extract of R. idaeus leaves using accurate mass measurement and characteristic fragmentation patterns. A total of 16 flavonoids, including 4 quercetin derivatives, 2 luteolin derivatives, 8 kaempferol derivatives and 2 isorhamnetin derivatives, were identified. Compounds 3: and 4: , Compounds 6: and 7: and Compounds 15: and 16: were isomers with different aglycones and different saccharides. Compounds 8: , 9: and 10: were isomers with the same aglycone and the same saccharide but different substituent positions. Compounds 11: and 12: were isomers with the same aglycone but different saccharides. Compounds 2: , 8: , 9: and 10: possessed the same substituent saccharide of glycuronic acid. Most of them were reported inR. idaeus for the first time.

The cycloaddition reaction of CO2 and various epoxides is one of the most promising approaches for CO2 fixation. Inspired by the synergistic catalysis mechanism based on the double activation model...

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