Uniform molecularly imprinted polymer (MIP) microspheres were prepared by precipitation polymerization of methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) using melamine as template in acetonitrileethylene glycol mixed solvent (20∶1

V/V).1HNMR and UV spectrometry were employed to demonstrate the mechanism of the interaction between melamine and MAA

and the structure of the polymer microspheres was characterized by scanning electron microscopic (SEM) photographs and IR spectrometry.The results showed that the melamineMAA complexes of 1∶2 mole ratio were obtained by cooperative hydrogen bonding.The MIP particles with many binding abilities on their surface were microspheres and the diameters ranging from 400 nm to 500 nm were larger than those of the nonimprinted polymer microspheres.The adsorption efficiency was investigated by equilibrium adsorption experiments.The data obtained showed that the imprinted polymer microspheres reached equilibrium after 4 h and had higher adsorption efficiency compared to the nonimprinted polymer microspheres

which had the same chemical composition.Scatchard plots analysis revealed that the apparent maximum binding capacity and the dissociation contents were Qmax1= 22.97 mol/g，Kd1 = 0.1410-3 mol/L for high affinity binding sites and Qmax2 = 157.65 mol/g，Kd2 = 2.5510-3 mol/L for low affinity binding sites

respectively.Thus

the apparent imprinting efficiency and the effective imprinting efficiency were calculated to be 68% and 58%

respectively.The melamine imprinted polymer microspheres synthesised in this method had better performance and could be used for separation

enrichment and analysis of melamine.