Highly selective extraction of baicalin in natural herbs and medicinal preparations by molecularly imprinted polymer

Selective extraction of bioactive compounds in natural products and traditional medicines is difficult but necessary for drug analysis and new drug development. In this study, baicalin-imprinted polymer particles were prepared for selective recognition and extraction of baicalin from herbs and traditional Chinese medicines. The molecularly imprinted polymer (MIP) was synthesized by co-polymerization of 4-vinylpridine and ethylene glycol dimethacrylate in the presence of baicalin with a ratio of 8 : 40 : 1, where N,N-dimethyl formamide/acetonitrile served as porogen. The prepared MIP particles showed good selectivity by comparing with non-imprinted polymer and possessed an imprinted factor of 2.17; selectivity to other molecules was also tested by extracting an analogue, naringin. The performances of the MIP particles were systematically investigated, including adsorption kinetics, isotherm experiment, and Scatchard analysis. The imprinted particles were also applied to extract baicalin from natural herb Plantago asiatica L, and traditional Chinese medicine Longdanxiegan bolus. The results showed that baicalin in these complex matrixes could be selectively extracted and well isolated with other components. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1873-1878, 2013