Grafting of doxycycline imprinted polymers on silica surface for selective solid-phase extraction in beef samples

Abstract

A molecularly imprinted polymer (MIP) for separation and enrichment of doxycycline (DC) has been synthesized using DC as the template, acrylamide-tung oil acid methyl ester (AM-ESA) and propenoic acid (AA) as the functional monomers, ethylene glycol dimethacrylate (EGDMA) as the cross-linker and 2,2′-azo-bis-isobutyronitrile (AIBN) as the initiator. The chemical and morphological characteristics of the MIPs were investigated by FT-IR and SEM. The static and kinetic adsorption, selectivity and recovery of the polymers were evaluated. The results indicated that the MIPs had higher chemical affinity for DC than the non-imprinted polymer (NIP). The maximum adsorption capacity of the DC-MIPs was calculated to be 257 μmol g⁻¹. Finally, the MIPs were successfully used as a stationary phase for solid-phase extraction (SPE) to enrich DC from beef samples and the recoveries were in the range of 92.5–96.4% with RSDs of 3.1–7.0%.