Effectively designed molecularly imprinted polymers for selective extraction of glabridin from Glycyrrhiza glabra L. residues by screening the library of non-imprinted polymers.

Molecularly imprinted polymers (MIPs) with high selectivity and affinity to glabridin were designed based on the screening results of the library of non-imprinted polymers (NIPs). The NIP library contained 48 polymers that were polymerized with the combinations of different functional monomers, cross-linkers, and porogenic solvents. The distribution coefficient (k) values were used to estimate the affinity of NIPs to glabridin. The corresponding MIPs of the best three NIPs were prepared. After evaluating the imprinting effects and selectivity of the three MIPs, the performance of the best MIP as solid phase extraction sorbent was investigated. Glabridin with percent recovery of 83 was obtained from the extract of Glycyrrhiza glabra L. (G. glabra L.) residues by molecularly imprinted solid phase extraction (MISPE). Thus, this material can be successfully used for the extraction and purification of glabridin from G. glabra L. residues.