Preparation and characterization of molecularly-imprinted polymers for extraction of sanshool acid amide compounds followed by their separation from pepper oil resin derived from Chinese prickly ash (Zanthoxylum bungeanum)

Abstract

Molecularly imprinted polymers were prepared using the molecular structure analogs of sanshool as template molecule, 2-vinylpyridine and β-cyclodextrin as double functional monomers, ethylene dimethacrylate as cross linker, and azobisisobutyronitrile as initiator. The structural characteristics of the polymers were determined by Fourier-transform infrared spectroscopy and scanning electron microscopy. Dynamic adsorption and isothermal adsorption were also investigated. The molecularly imprinted polymers were used to prepare a molecularly imprinted solid-phase extraction column in order to separate acid amide components from pepper oil resin derived from Chinese prickly ash (Zanthoxylum bungeanum). After eluting, the percentage of acid amide components was enhanced to 92.40 ± 1.41% compared with 23.34 ± 1.21% in the initial pepper oil resin, indicating good properties of purification of molecularly imprinted polymers and potential industrial application.

Keywords: Chinese prickly ash; functional monomers; molecularly-imprinted polymers; solid-phase extraction; traditional Chinese medicine.