| The harmful elements and complex matrix interference in plant medicine pose a high challenge to the removal,purification and detoxification of high-quality medicinal plants.Up to now,there are relatively few studies on the removal and purification of harmful elements in the whole industrial chain of medicinal plants at home and abroad.This subject,combined with ICP-MS and HPLC technology,has investigated the content and distribution characteristics of various types of inorganic elements and active ingredients in plant drugs.Based on the interdisciplinary technologies of magnetomechanics,electrospinning technology,electrochemical technology and solid phase adsorption,and for Hg,Cd,Pb and other harmful elements with high toxicity and easy to pollute medicinal plants have formed a series of highly efficient and environmentally friendly modified chitosan nano-spun fiber materials and purification and removal systems,which are used for the removal and purification of harmful elements in plant drugs and their preparations,and have evaluated the loss of the modified nanofiber materials on the effective components,the impact on the quality and quality of medicinal plants,and the biological safety,It provides certain data support and technical reference for the research on the removal and purification of harmful elements in plant medicine.The implementation of this project has both theoretical and practical significance in reducing the pollution and harm of harmful elements in medicinal plants,ensuring the quality of medicinal plants and the safety of people’s medication.The main contents and corresponding results of the study are as follows:1.Based on inductively coupled plasma mass spectrometry(ICP-MS),multiple types of harmful elements in medicinal plants such as Astragalus membranaceus,Codonopsis pilosula,Salvia miltiorrhiza and Angelica sinensis were analyzed,and the content levels of more than 20 kinds of elements were analyzed,which laid an experimental foundation for the characterization of material removal effect in the future.The test results showed that among the 19 batches of medicinal plants,Salvia miltiorrhiza and Codonopsis pilosula were plants with high Se content,and Astragalus membranaceus and Astragalus membranaceus were plants rich in Fe and Ca elements.According to the requirements of the maximum residue limit value in the 2020 edition of Chinese Pharmacopoeia,no harmful elements exceeded the standard in Angelica sinensis.Among the 5 batches of Salvia miltiorrhiza,1 batch of Hg exceeded the standard,and 1 batch of Cr exceeded the standard.In Codonopsis pilosula and Angelica sinensis,one batch of Cr element exceeded the standard,which had certain health risks and safety hidden dangers.2.Chitosan hydrogel and chitosan electrospinning fiber membrane were designed and prepared.The removal efficiency of harmful elements and the interference of drug effect were investigated.In the experiment,the preparation and removal parameters of hydrogel and electrospinning were optimized,and the kinetics and removal effects of the two adsorbents were investigated.The results showed that the removal effect of chitosan electrospinning membrane was better than that of hydrogel,and the removal rates of Hg,Cu and Pb in aqueous solution were 95.3%,72.1% and 44.2%,respectively.However,the removal effect of chitosan hydrogel on medicinal plant aqueous solution was better than that of electrospinning fiber membrane materials.The removal rates of Cu in Astragalus and Angelica were 63.6%and 44.7% respectively.3.In order to enhance the selective removal ability of chitosan materials in medicinal plant solution and reduce the interference of pharmacodynamic components,this topic designed and prepared modified chitosan nanomaterials,characterized the morphology,structure,thermal stability and other parameters of the modified chitosan materials,and explained the adsorption mechanism of the modified materials by combining the kinetic adsorption model and infrared spectroscopy.Finally,it was applied to study the removal effect of harmful elements.The results showed that the material showed superior removal efficiency in aqueous solution,the removal rates of Hg,Cu,Cd and Pb reached 97.7%-53.6%,and showed specific adsorption in the water decoction of Codonpsis pilosula,the corresponding removal rates reached100%(Hg)-35.1%(Cd).The similarity of fingerprint before and after removal was0.999,indicating that the material had little interference on chemical composition.In conclusion,the purification system based on modified chitosan nanomaterials can be preliminarily applied to the purification and removal of harmful elements in the aqueous decoction of medicinal plants. |
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