Polymer-based stimuli-responsive systems for protein capture: capacity, reversibility, and selectivity

To develop effective (chromatography-like) separation systems, it's crucial to control protein interactions. Stimulus-responsive polymers, or “smart coatings,” have emerged as a promising tool for achieving superior control by dynamically adjusting their physicochemical properties in response to stimuli like pH, temperature, salt, CO₂, or an electric field. This review provides an overview of protein capture systems that incorporate stimulus-responsive polymers and examines how conformational changes underlie the switch in protein-surface interactions. Specifically, we highlight the importance of a high adsorption capacity and selectivity for efficient capture, as well as reversibility for material reusability and sustainability. Our focus is on the key characteristics that determine the possibility of scaling up towards industrial separation systems with complex, diluted protein streams. Finally, we offer suggestions for further enhancement and identify critical investigation areas to drive the advancement of these innovative stimuli-driven separation techniques.