Surface imprinting of pepsin via miniemulsion polymerization

Surface imprinted polymers allow accessibility of the selective binding sites to large molecules such as proteins. In this work, small polymer particles offering a large surface area were prepared via miniemulsion polymerization in the presence of pepsin serving as a template molecule. The influence of four different functional monomers and of the amount of the template on the imprinting effect of pepsin was investigated. After the miniemulsion polymerization and a washing step, stable polymer suspensions with an average particle diameter of 400-600 nm and a specific surface area of 30-65 m² g^-1 were obtained. The results of detailed rebinding experiments revealed that the highest imprinting effect was achieved with (3-acrylamidopropyl)trimethylammonium chloride as a functional monomer and a high amount of the template. These polymer particles also showed selectivity for pepsin against various proteins. This approach provides a fundamental step towards the development of synthetic protein receptors and protein scavenger materials useful in biomimetic assays and for clean-up in biotechnology.