Examination of the Chemical Composition of Propolis IX. Solid Phase Extraction of Coumarins from Propolis by Using Molecularly Imprinted Polymer

Abstract

The group selective molecularly imprinted polymers (MIPs) for coumarins, including umbelliferone, herniarin, 4-methylumbelliferone, scoparone were developed. Using umbelliferone as the template molecule, methacrylic acid as functional monomer, ethylene glycol dimethacrylate as linking agent, chloroform as porogen and bulk polymerization as synthetic method, the MIPs were synthesized and characterized with rebinding experiments. The characteristics of MIPs were evaluated by chromatographic method and frontal analysis, and demonstrating good selectivity and high binding capacity (269 μg of umbelliferone per 100 mg of polymer). The group selective MIP was used as sorbent for the SPE pretreatment of coumarins from propolis extracts prior to HPLC analysis. Analysis of the samples showed good recoveries (>70 %). The limits of quantitation (LOQs) for studied compounds were 0.3-10 ng.mL^-1 (determined for fluorescence detection).