Selective adsorption of active ingredients liquiritin and isoliquiritin from Glycyrrhiza uralensis Fisch with multi-walled carbon nanotubes(MWNTs) has been studied.Distribution coefficients of liquiritin between ethanol solvent and r-MWNTs or o-MWNTs in 293K is 37.5 and 43.3,while the distribution coefficients of isoliquiritin between ethanol solvent and r-MWNTs or o-MWNTs is 717 and 1080,respectively.It was indicated that the distribution coefficient of isoliquiritin adsorbed by MWNTs was much larger than that of liquiritin,and oxidation treatment of MWNTs could obviously enhance their adsorption ability.The possible reasons that MWNTs can selectively adsorb isoliquiritin other than liquiritin were discussed on the bases of molecular structure of the active ingredients and their interaction with nanotubes.
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B.Wang W.Y.Feng~* M.T.Zhu Y.Wang Y.L.Zhao~* Z.F.Chai (Laboratory for Bio-Environmental Effects of Nanomaterials and Nanosafety,Key Laboratory of Nucelar Analytical Techniques,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing,100049,China
With large-scale production and application at large scale, carbon nanotubes (CNTs) may cause ad-verse response to the environment and human health. Thus, study on bio-effects and safety of CNTs has attracted great attention from scientists and governments worldwide. This report briefly summa-rizes the main results from the in vitro toxicity study of CNTs. The emphasis is placed on the descrip-tion of a variety of factors affecting CNTs cytotoxicity, including species of CNTs, impurities contained, lengths of CNTs, aspect ratios, chemical modification, and assaying methods of cytotoxicity. However, experimental information obtained thus far on CNTs' cytotoxicity is lacking in comparability, and some-times there is controversy about it. In order to assess more accurately the potential risks of CNTs to human health, we suggest that care should be taken for issues such as chemical modification and quantitative characterization of CNTs in cytotoxicity assessment. More importantly, studies on physical and chemical mechanisms of CNTs' cytotoxicity should be strengthened; assaying methods and evaluating criteria characterized by nanotoxicology should be gradually established.
ZHU Ying1,2 & LI WenXin1 1 Laboratory of Nano-biology and Medicine, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China