Preparation and characterization of erythromycin surface molecularly imprinted polymers based on two-step distillation-precipitation polymerization

Surface molecularly imprinted polymers (SMIPs) with a core-shell structure were prepared through a novel two-step distillation precipitation polymerization (DPP) method. The first-step DPP allowed formation of cores composed of copolymeric microsphere of methacrylic acid and divinylbenzene (PMAA-co-DVB), and in the second-step DPP, the core was modified with a molecularly imprinting layer with erythromycin (EM) as template, methacrylic acid (MAA) as functional monomer, divinylbenzene (DVB) as crosslinking agent and azobisisobutyronitrile (AIBN) as initiator. Laser particle size determination, scanning electron microscope (SEM) and a series of binding tests were employed to characterize the morphology and the binding properties of the obtained SMIPs. It showed that when the fraction of the monomers was 7 vol% in the whole reaction system, the prepared PMAA-co-DVB microspheres afforded good morphology and monodispersity. Moreover, when the molar ratio of MAA to EM was 1:4 and the fraction of the monomers was 2. 8 vol% in the secondstep DPP, the synthesized SMIPs displayed optimal binding performance with the maximum binding capacity of 76. 8 mg/g and the binding saturation time of 90 min. Meanwhile, the produced SMIPs exhibited higher binding ability to the template molecule-EM, compared with its analogue, roxithromycin.