Affinity control of immobilized metal ligands with proteins using thermoresponsive nanogel-like interfaces

In the present research, we newly developed thermoresponsive nanobio interfaces for possible applications in affinity regulations. We introduced thermoresponsive polymers having metal chelating segments (iminodiacetic acid moiety on the side chains) onto animated silica beads surfaces. Utilizing thermoresponsive expanding-contracting changes of poly(N-isopropylacrylamide) on the bead surfaces, we succeeded in on-off regulation of specific affinity interactions between immobilized metal ligands and lysozyme having one histidine residue. The obtained results suggest that affinity modulation can be achieved by utilizing thermally regulated polymer chain hydration changes without any use of competitive agents.