Temperature-responsive chromatography using a functional polymer modified stationary phase with molecular recognition sites

A novel packing materials for high-performance liquid chromatography (HPLC) was developed, which is silica gel, modified with a temperature-responsive polymer (N-isopropylacrylamide) (PNIPAAm) surface. The advantage of this system is that it works with an aqueous mobile phase, without using an organic solvent. Therefore the separation of biomolecules can be achieved without loss of their activity. In this study, we introduced a proline derivative and a naphthylalanine derivative as molecular recognition sites into PNIPAAm chains. As a result, the selectivity of separation was enhanced by CH-π interaction and n-n interaction, respectively. This result suggested that a temperature-responsive chromatography system utilizing PNIPAAm derivatives would be useful for biomolecule separation. Temperature-responsive chromatography is expected to be applicable to the separation of bioactive species in various fields, such as medical and pharmaceutical science.