Phosmet Molecularly Imprinted Polymer Synthesis And Application

In this dissertation, we explored a new sample pretreatment, the molecularly imprinted-solid phase extraction, to extract phosmet pesticide residues from plant-derived samples that contain complex matrix, such oats, peach, et al. In this paper, this phosmet-imprinted polymer (MIPs) was prepared by bulk polymerization, and its recognition property was characterized by static and kinetic adsorption model. In the end, the MIPs were used to the sorbent of solid phase extraction to extract phosmet residues from several plant-derived samples. An extraction protocol developed in this dissertation resulted in a reliable MISPE method suitable for HPLC analysis.Synthetic solvents, functional monomer, crosslinker, the ratio between template molecule, functional monomer and cross linker were optimized in detail, we ultimately chosed3mL THF and1mL toluene,1mmol of the phosmet molecules,4mmol MAA, and4mmol TRIM as the main materials of synthesis. The MIPs synthesized with above materials obtained a satisfied adsorption and specificity.The imprinted polymer held fast uptake kinetics tested by kinetic adsorption experiment. The recognition property of the MIPs was evaluated by static adsorption test. The data obtained in equilibrium adsorption experiment was processed by Scatchard analysis, which displayed that the MIPs had one affinity binding sets. When methyl parathion and chlorpyrifos were used as competitive molecules, the values of the distribution coefficient (kd) is1.33and2.34, the values of the selectivity coefficient (K) and relative selectivity coefficient (K) of static adsorption is1.07and1.47, which All exhibited that MIPs have a good recognition characteristic.This polymer was used as a molecular imprinted solid-phase extraction sorbent to selectively preconcentrate phosmet from plant-derived samples. An extraction protocol for aqueous standards was developeded by optimizing loading, washing and eluting conditions. The extraction protocol result to a satisfactory recovery of phosmet in sample with72%～98%, and The RSDs of recovery inferior to3%and revealed that MISPE could be applied for cleaning sample and enriching the template in the complicated samples. Comparison with C18, the MIPs had advantages for clean-up samples, especially excellent adsorption and selectivity.