Preparation and Adsorption Ability of Molecularly Imprinted Polymer Microspheres for Malachite Green

Molecularly imprinted polymer (MIP) microspheres were synthesized through precipitation polymerization using malachite green (MG) as template, methacrylic acid (MAA) as monomer, and trimethylolpropane trimethacrylate (TRIM) as cross-linker. The microsphere structure of MIP was characterized by IR spectroscopy and SEM. The influence of preparation conditions such as monomer and cross-linker dosages on the polymer absorption of MG in acetonitrile solution was also explored. Under the optimum synthesis conditions (0.25 mmol MG, 1.5 mmol MAA, 2.5 mmol TRIM, 40 mL acetonitrile), the prepared MIP microspheres have a binding capacity as high as 2000 µg g−1 of MG with an imprinting factor of above 4.0. The result suggests that the prepared MIP microspheres are promising material for the selective extraction of MG in complicated matrix solutions.