Abstract: Pyrazosulfuron-ethyl molecularly imprinted polymers (PS-MIPs) have been synthesized by the molecular imprinting technique using pyrazosulfuron-ethyl (PS) as the template molecule, methacrylic acid (MAA) as the functional monomer, azobisisobutyronitrile (AIBN) as the initiator and trimethylolpropane trimethacrylate (TRIM) as the cross-linking agent. Three different porogens were used to synthesise PS-MIPs, and the effect of porogen volume on the adsorption capacities and the particle size of the MIPs were evaluated. The results showed that the MIPs that utilised dichloromethane as the porogen exhibited higher binding capacities than those prepared with n-hexane or n-hexane: dichloromethane (volume ratio 1:1). The porogen volume had little effect on the adsorption capacities, but it clearly affected the particle size. The largest particle size was obtained for MIP3 (D50=5.36 μm) when 36mL of dichloromethane was used as the porogen and the materials also had a high adsorption capacity of 3321.29 μg/g. The polymers were studied by scanning electron microscopy and infrared spectroscopy and the imprinting sites in MIP could be clearly observed. The PS-MIPs synthesized by the above method showed high selectivity for PS in selective adsorption experiments. The adsorption capacity of PS-MIPs for PS, bensulfuron-methyl (BSM), tribenuron-methyl (TBM), metsulfuron-methyl (MSM) and nicosulfuron (NS) were 1146.19, 1044.21, 1087.27, 1051.92 and 1023.89 μg/g, respectively.
Template and target information: pyrazosulfuron-ethyl, PS
Author keywords: pyrazosulfuron, molecularly imprinted polymer, Infrared spectroscopy, adsorption capacity