Preparation and application of cellulose-based molecularly imprinted polymers for the targeted separation of esculetin

A novel molecularly imprinted polymer(Esc-SMIPs) with specific selectivity for esculetin (Esc), was synthesized in this work. Dehydroabietic acid [2-(acryloyloxy) ethyl] ester (DAAEE) and 4-vinylpyridine (4-VP) were utilized as bifunctional monomers, and porous cellulose microspheres derived from traditional Chinese medicine residue were employed as the carrier. The polymer was characterized by FT-IR, SEM, BET, TEM, and TGA. Experimental results demonstrated that the Esc – SMIPs prepared by these bifunctional monomers exhibit higher adsorption capacity (37.12 mg/g) and a superior imprinting factor (2.55) compared with the SMIPs derived from other monomers (PS, AA, 4 - VP, AM and DAAEE). In addition, Esc – SMIPs were applied as the solid – phase extraction filler for the selective identification and separation of Esc from Cortex fraxini extract. The concentration of Esc in the eluent (70% ethanol) was found to be significantly higher than that in the Cortex fraxini extract. The recovery rates of spiked samples for Esc were in the range of 98.06% − 101.93%, with relative standard deviation (RSD) values below 1.86%. When compared with macroporous adsorption resin D101 or Esc – SNIPs, excellent targeted enrichment and high separation efficiency for Esc are possessed by Esc – SMIPs.