EDTA修饰的壳聚糖磁性吸附剂对当归提取液中的重金属的去除

Removal of heavy metals from extract of Angelica sinensis by EDTA-modified chitosan magnetic adsorbent

中药提取液中的重金属不仅含量低,而且还易与提取液中的多种有机组分产生络合作用,一般很难高效脱除。该文应用EDTA修饰的壳聚糖磁性吸附剂(EDTA-modified chitosan/SiO2/Fe3O4,简称EDCMS)对当归提取液中低浓度的重金属进行了吸附脱除实验。结果表明EDCMS对提取液中低浓度的重金属如铜,镉,铅等具有很高的去除效率,其中对镉、铅的去除率可分别达到90%,94.7%。此外,EDCMS对药液中的其他重金属如锌、锰等也有一定的脱除作用,但在脱除重金属过程中,药液中的含固量、阿魏酸的含量以及HPLC指纹图谱等均无显著变化。上述实验结果提示EDCMS对重金属的去除过程不会引起当归药液中主要药效成分的变化。

The concentrations of heavy metals in the extracting solutions of traditional Chinese medicine are usually very low. Furthermore, a vast number of organic components contained in the extracting solutions would be able to coordinate with heavy metals, which might lead to great difficulty in high efficient removal of them from the extracting solutions. This paper was focused on the removal of heavy metals of low concentrations from the extracting solution of Angelica sinensis by applying an EDTA-modified chitosan magnetic adsorbent （EDTA-modified chitosan/SiO2/Fe3O4,abbreviated as EDCMS）. The results showed that EDCMS exhibited high efficiency for the removal of heavy metals, such as Cu, Cd and Pb, e.g. the removal percentage of Cd and Pb reached 90% and 94.7%, respectively. Besides, some amounts of other heavy metals like Zn and Mn were also removed by EDCMS. In addition, the total solid contents, the amount of ferulic acid and the HPLC fingerprints of the extracting solution were not changed significantly during the heavy metal removal process. These results indicate that EDCMS may act as an applicable and efficient candidate for the removal of heavy metals from the extracting solution of A.sinensis.keywords：EDTA modified chitosan