Polyethylene glycol functionalized Fe3O4@MIL-101(Cr) for the efficient removal of heavy metals from Ligusticum chuanxiong Hort

In recent years, the quality and safety issues of Chinese medicinal herbs have received great attention worldwide. Thereinto, heavy metal contamination has been one of the most serious concerns. Compared to the wide research in the analysis of heavy metals in medicinal herbs, the studies on the removal of heavy metals are relatively limited. In this study, polyethylene glycol functionalized Fe3O4@MIL-101(Cr) (Fe3O4@MIL-101(Cr)@PEG) was designed and synthesized to remove heavy metals from the decoction of Ligusticum chuanxiong Hort. The in-house fabricated Fe3O4@MIL-101(Cr)@PEG was characterized by a porous structure and a large specific surface area. Then, the efficiency of the material for the removal of five heavy metals was tested under optimal adsorption conditions. Meanwhile, the content of Senkyunolide A, Senkyunolide I, and Ferulic acid, the solid content, and the HPLC fingerprints similarity were used as the quality monitoring indicators of Ligusticum chuanxiong Hort decoction before and after the heavy metal removal. Results showed that the magnetic nanomaterial had excellent removal efficiency for As5+ (81.4 %), Cd2+ (88.19 %), and Pb2+ (83.79 %) and certain removal efficiency for Ni2+ (51.59 %) and Zn2+ (55.4 %) under the spiked concentration of 50 lg/mL. The content of Senkyunolide A, Senkyunolide I, and Ferulic acid were decreased by less than 8.00 % after the removal of heavy metals. Besides, the loss rate of solid content was only 0.18 %, and the finger prints similarity was over 99.9 %. The results indicated that Fe3O4@MIL-101(Cr)@PEG could effi-ciently and selectively remove heavy metals from Ligusticum chuanxiong Hort without affecting its effective components. Due to the advantages of low-cost, simple manipulation, and good efficiency, the material can be recommended for heavy metals removal from the aqueous solutions of medic-inal herbs, providing a new and promising application for the removal of exogenous contaminants in medicinal herbs.(c) 2023 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

In recent years, there has been great attention worldwide to the quality and safety issues of Chinese medicinal herbs, especially heavy metal contamination. This study designed and synthesized a magnetic nanomaterial, Fe3O4@MIL-101(Cr)@PEG, to efficiently remove heavy metals from Ligusticum chuanxiong Hort decoction. The results showed that the nanomaterial had good removal efficiency for As5+, Cd2+, and Pb2+, with certain removal efficiency for Ni2+ and Zn2+, without significantly affecting the effective components of the decoction. This material is recommended for heavy metal removal from aqueous solutions of medicinal herbs.