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A novel functional absorbent, polyvinyltetrazole fiber (PVT), was made from polyacrylonitrile fiber through [3+2] azide‐nitrile cycloaddition reaction of cross‐linked polyacrylonitrile with sodium azide. The obtained PVT showed strong adsorption ability to the investigated heavy‐metal ions, Cu(II), Cd(II), Ni(II), and Zn(II), with the maximum adsorption capacities of 323, 278, 200, and 175 mg g−1, respectively. The adsorption process was described as an ion exchange mechanism. The adsorption isotherms were better fitted for Langmuir model, while adsorption kinetics was better described by the pseudo‐second order equation. In addition, the tested heavy‐metal ions could be desorbed efficiently from PVT at pH below 2.0, and the adsorption capacity of the regenerated PVT had no loss until seven cycles. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

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An expeditious and effective HPLC-UV method has been developed for the simultaneous determination of seven major flavonoids in Apocyni Veneti Folium (AVF) extract. The chemical profile of seven flavonoids, including quercetin-3-O-β-D-glc(2 → 1)-β-D-glucoside, rutin, isoquercetin, kaempferol-3-O-β-D-glucoside, quercetin-3-O-(6″-O-malonyl)-β-D-glucoside, quercetin and kaempferol was acquired by HPLC-UV. The analysis was performed on a Diamosil C18 analytical column with a gradient solvent system of acetonitrile-0.1% aqueous acetic acid. Full validation of the method was carried out (linearity, reproducibility, repeatability, accuracy and limit of detection). The results indicated that the contents of investigated flavonoids in Apocyni Veneti Folium varied significantly from habitat to habitat, with contents ranging from 0.01 to 5.57 mg g⁻¹. The antioxidant activity results demonstrate that the seven flavonoids showed great efficiency in scavenging DPPH radicals. The high content of flavonoid components of AVF could be responsible for its high antioxidant activity. This study provides powerful evidence for the relationship between the chemical ingredients of and bioactivity in AVF.