Preparation and characterization of dummy molecularly imprinted polymers for separation and determination of farrerol from Rhododendron aganniphum using HPLC

Abstract

A dummy molecularly imprinted polymer (d-MIP) was developed for extraction and cleanup of farrerol from Rhododendron aganniphum. The d-MIP was prepared by precipitation polymerization using quercetin as the dummy template, 4-vinylpyridine as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, and acetonitrile as the porogen. The d-MIP was characterized by scanning electron microscopy and Fourier-transform infrared spectroscopy. Dynamic curves, adsorption isotherms, and Scatchard plots showed the d-MIP had good affinity, capacity, and selectivity for the target compound. The prepared d-MIP was used as a sorbent in solid-phase extraction cartridges and successfully applied to specific extraction and purification of farrerol from real samples. High recoveries were obtained for four spiked levels of farrerol in Rhododendron aganniphum using d-MIP solid-phase extraction coupled with high-performance liquid chromatography. The linear range was 1–100 µg mL−1, the limit of detection was 2.23 mg kg−1, the farrerol recovery range was 85.7%–104.1%, and the relative standard deviations (n = 3) were all less than 2.2% for real samples. The proposed method provides a simple, rapid, and environmentally friendly approach to the analysis of farrerol in complex herbal products.