Uniform-sized clenbuterol molecularly imprinted polymers prepared with methacrylic acid or acrylamide as an interacting monomer

Clenbuterol molecularly imprinted polymer microbeads were prepared with a two-step swelling and thermal polymerization technique with either methacrylic acid or acrylamide (AAm) as the monomer and ethylene glycol dimethacrylate as the crosslinker at different monomer/crosslinker ratios. The quality of the microbeads, in terms of shape, size distribution, rigidity, and monomer incorporation, was evaluated as a function of the reaction parameters. A good imprinting effect was obtained with both systems, as assessed by high-performance liquid chromatography (HPLC) experiments with phosphate-buffered saline/acetonitrile eluents, with a complete baseline separation of clenbuterol with respect to other beta-adrenergic agents obtained. When AAm was used as the monomer, improved control of the polymerization process was achieved, producing microbeads with lower polydispersity and no lack of separation capacity. (C) 2002 John Wiley Sons, Inc.