Selective Adsorption and Purification of the Acteoside in Cistanche tubulosa by Molecularly Imprinted Polymers

Abstract

Acteoside (ACT) is the main component of phenylethanoid glycosides in Cistanche tubulosa, and it is extremely desirable for obtaining high purification of ACT by molecularly imprinted polymers (MIPs) from their extracts. In this study, MIPs were designed and synthetized to adsorb selectively the ACT in C. tubulosa. The effects of different functional monomers, cross-linkers, and solvents of MIPs were investigated. MIPs were studied in terms of static adsorption experiments, dynamic adsorption experiments, and selectivity experiments. The optimal functional monomer, cross-linking agent, and solvent are 4-vinylpyridine, ethylene glycol dimethylacrylate, and the mixed solvent (acetonitrile and N,N-dimethylformamide, 1:1.5, v/v), respectively. Under the optimal conditions, the synthesized MIP1 has a high adsorption performance for ACT. The adsorption capacity of MIP1 to ACT reached 112.60 mg/g, and the separation factor of ACT/echinacoside was 4.68. Because the molecularly imprinted cavities of MIP1 resulted from template molecules of ACT, it enables MIP1 to recognize selectively ACT. Moreover, the N-H groups on MIP1 can form hydrogen bonds with the hydroxyl groups on the ACT; this improves the separation factor of MIP1. The dynamic adsorption of ACT accorded with the quasi-second-order kinetics; it indicated that the adsorption process of MIP1 is the process of chemical adsorption to ACT. MIPs can be applied as a potential adsorption material to purify the active ingredients of herbal medicines.

Synthesis and Characterization of a New Molecularly Imprinted Polymer for Selective Extraction of Mandelic Acid Metabolite from Human Urine as a Biomarker of Environmental and Occupational Exposures to Styrene

“…The results demonstrate that 4-VP was successfully polymerized into the MIPs. The presence of the template, which formed hydrogen bonds with 4-VP, probably caused a relatively broad peak at 3629 cm −1 compared to the NIP and MIP infrared spectra (after washing) [ 43 ]. Therefore, the results from the FT-IR spectra suggest that the MIPs were properly synthesized.…”

Studies on Cistanches Herba: A Bibliometric Analysis

“…Recent studies demonstrated that the active ingredients of C. tubulosa can be better purified using novel adsorption materials (molecularly imprinted polymers, mesoporous carbon, etc.) [11,12]. Presently, scholars are dedicated to the study of the pharmacologically active ingredients and related mechanisms of action of Cistanche through advanced analytical identification techniques, such as ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS).…”

A Universal Mathematical Methodology in Characterization of Materials for Tailored Design of Porous Surfaces

“…Adsorption phenomena have numerous industrial and environmental applications, such as desalination, cooling, wastewater treatment, gas or heat storage, and air purification (Burhan et al, 2016a , 2017 , 2018a , 2019a , 2020 ; Xie et al, 2018 ; Oh et al, 2019 ; Shahzad et al, 2019a , b ; Zhao et al, 2020 ). Such processes involve distinct interaction of adsorbate molecules over the porous surface of adsorbent material.…”