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Room-temperature ionic liquids (ILs) are liquids that are constituted entirely of ions and can provide a solvent environment quite unlike any other available at room temperature. They continue to attract considerable interest in the chemistry research community as they are good solvents for a wide range of both inorganic and organic materials. In this study, a CZE method has been established for resolving natural flavonoids, quercetin, kaempferol and isorhamnetin in the Chinese herbal extract from Hippophae rhamnoides and its medicinal preparation (Sindacon Tablet). In this method, 1-alkyl-3-methyl-imidazolium-based ILs are used as the additive, and the effects of the alkyl group, imidazolium counterion (anionic part), along with the concentration of IL are investigated and discussed. Baseline separation, high efficiencies and symmetrical peaks of the three flavonoids were obtained. The separation mechanism seems to be the hydrogen-bonding interaction between the imidazolium cations of IL and the flavonoids.

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A simple and rapid capillary electrophoretic method was developed for the simultaneous determination of noradrenaline (NA) and dopamine (DA) in Portulaca oleracea L. The buffer solution used in this method was 40 mM tris (hydroxymethyl) aminomethane (Tris)-H3PO4 at pH 2.00 containing 15% methanol. The effects of pH value, organic modifier, and applied voltage were investigated. The linear ranges of NA and DA were 0.5-100 microg/mL (r=0.9952) and 6.25-200 microg/mL (r=0.9992), respectively. The relative standard deviations of the corrected peak area were 6.73% and 4.26%, respectively. NA and DA in Portulaca oleracea L. were simultaneous determined successfully within 5.6 min. In this way, the contents of NA and DA in different parts (stem, leaves, and seeds) of P. oleracea L. and in different extracts of leaves with different solvents (distilled water, 50% methanol, and methanol) were studied.

The development of efficient and stable catalyst systems using low-cost, abundant, and nontoxic materials is the primary demand for photocatalytic water oxidation. Distinguishing the true active species in a heterogeneous catalytic system is important for construction of efficient catalytic systems. Herein, hydrothermally synthesized Ti3+ self-doped TiO2, labeled as Ti3+/TiO2, was first used as a light absorber in a powder visible light-driven photocatalytic water oxidation reaction. When an iron-containing polyoxometalate Na27[Fe11(H2O)14(OH)2(W3O10)2(α-SbW9O33)6] (Fe11) was used as a cocatalyst, an amorphous layer of active species was wrapped outside the initial Ti3+/TiO2 nanorod and the in situ formed composite was labeled as F/Ti3+/TiO2. When the composite F/Ti3+/TiO2 was tested as a photocatalytic water oxidation catalyst, dramatically improved oxygen evolution performance was achieved. The composite F/Ti3+/TiO2 showed an oxygen evolution rate of 410 μmol/g/h, which was about 11-fold higher than that of prism Ti3+/TiO2. After 24 h of illumination, an O2 yield of 36.4% was achieved. The contrast experiments, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy characterization demonstrated that FeO x is the true cocatalyst that enhanced the oxygen evolution activity of TiO2. A recycling experiment proved that the composite F/Ti3+/TiO2 has favorable stability in the oxygen production process.

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