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In this paper, two new amino acid imidazole ionic liquids IL‐3 and IL‐4 were synthesized for the first time, and their separation performance as the stationary phase for capillary gas chromatography (GC) was tested. The statically coated IL‐3 and IL‐4 capillary columns exhibited moderate to high polarity, and achieved the column efficiency of 2242 plates/m and 2487 plates/m respectively determined by n‐octanol at 120 °C. Importantly, the IL‐3 and IL‐4 columns exhibited excellent separation capability for analytes with varying polarity, including n‐alkanes, arenes, esters, alcohols, bromoalkanes, halogenobenzenes, and halogenated anilines. In addition, the IL‐3 and IL‐4 columns presented high selectivity and separation capability for positional, structural and cis‐/trans‐isomers. In particular, they showed high separation performance of the chloroaniline, bromaniline, iodoaniline and xylidine isomers as an important environmental pollutant. The IL‐3 and IL‐4 columns displayed advantageous resolving capability over the commercial HP‐35 column for aromatic amine isomers, and the separation performance of IL‐4 with long carbon chain was better than that of IL‐3. Moreover, it was applied to determine isomer impurities in real samples, and showing huge potential in GC applications. This work demonstrates the potential of the amino acid imidazole ionic liquids as a new type of stationary phase in GC separations. [ABSTRACT FROM AUTHOR]

The estrogenic effects of six components (ecdysterone, saffcomin A, tanshinone I, tanshinone IIA, psoralen and isopsoralen) isolated from Chinese herbs on cell proliferation and cell cycle in cultured breast cancer cells (MCF7) were analyzed using MTT assay and flow cytometry. Estrogenic effects of these components were also examined in presence of estrogen receptor (ER) antagonist, ICI180,782. The proliferation of MCF7 cells was increased significantly following treatment with either ecdysterone, saffcomin A, psoralen or sopsoralen. The cell cycle was enhanced from G1 to S by the treatment. The effects of the components on boosting proliferation were inhibited by adding ICI180,782. In contrast to the above 4 compounds, Tanshinone I and tanshinone IIA showed inhibitory effects on the cell proliferation, but the effects were also blocked by ICI182,780. The results suggest that ecdysterone, saffcomin A, psoralen and isopsoralen are estrogenic, but tanshinone I and tanshinone IIA produce anti-estrogenic effects. Both estrogenic and anti-estrogenic effects of the components are mediated through ER. [ABSTRACT FROM AUTHOR]