Abstract: Objective To prepare molecularly imprinted polymer (MIP) microspheres of α-tocopherol by precipitation polymerization and the conditions optimization, moreover, the products absorption property were evaluated. Methods The MIPs of α-tocopherol were synthesized by precipitation polymerization by using methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) and acetonitrile as functional monomer, cross-liker and solution, respectively. The morphology of the MIP microspheres was characterized by scanning electron microscope (SEM) and the corresponding effect factors were optimized. Results The optimal conditions were as follows: acetonitrile as solvent; reaction temperature at 60 °C; 0.20 mmol template molecule (α-tocopherol) and 40 mg initiator (azobisisobutyronitrile, AIBN); and stirring speed at 100 r/min. The absorption property and the binding characteristics of the MIPs were evaluated by equilibrium binding experiment and Scatchard analysis. The results showed that two classes of binding sites were produced in the polymer matrix, their dissociation constant (Kd) and the apparent maximum equilibrium binding capacity (Qmax) were 0.995 mmol/L, 22.420 μmol/g for high affinity binding sites and 0.458 mmol/L, 15.865 μmol/g for low affinity binding sites. Conclusion Under optimal conditions, the α-tocopherol MIPs showed good morphology of microsphere with particle size around 200 nm and good absorption of α-tocopherol.
Template and target information: α-tocopherol
Author keywords: α-Tocopherol, Molecularly imprinted polymer microspheres, precipitation polymerization