Uniformly imprinted polymer microspheres were prepared by precipitation polymerization in chloroform.MCP(monocrotophos),MAA(methacrylic acid),EGDMA(ethylene glycol dimethacrylate) and AIBN(azobisisobutyronitrile) were used as template,functional monomer,crosslinker and initiator,respectively.UV and IR spectra were used to demonstrate the mechanism of the interaction between MCP and MAA.It was found that one MCP was entrapped by three MAA molecules in chloroform.Langmuir model was used to fit the adsorption data,the results showed that the MCP imprinted polymer microspheres showed specific binding sites to the MCP.The data obtained in equilibrium adsorption experiments were processed by Scatchard analysis,the dissociation contents(KD1) and the apparent maximum binding capacity (Bmax1) were KD1=0.062?mmol/L,Bmax1=3.26?μmol/g for high affinity binding sites and KD2=3.03?mmol/L,Bmax2=65.70?μmol/g for low affinity binding sites,respectively.The MCP imprinted polymers have showed higher affinity to MCP than to the other organophosphorus pesticide used.So the imprinted polymers microspheres can be used for trace pesticide residue separation,enrichment and analysis.
Molecularly imprinted microspheres (MIP) for monocrotophos have been prepared by precipitation polymerization in acetonitrile (ACN) 60℃,24 h,using methacrylic acid (MAA),ethylene glycol dimethacrylate (EGDMA) and 2, 2-azobisiobutyronitrile (AIBN) as functional monomer,cross-linker and initiator,respectively.The recognition mechanism was elucidated by UV-vis spectra and computer modeling.Equilibrium binding experiment was employed to investigate the rebinding properties,Scatchard analysis showed that specific binding sites formed in the imprinted microspheres,and there were two kinds of binding sites,one was high binding sites,the other was low binding sites.This microspheres can be useful affinity absorbent used for organophosphorus pesticides separation and purification in food and environmental analysis.