Interfaces functionalized with polymers are known for providing excellent resistance towards biomolecular adsorption and for their ability to bind high amounts of protein while preserving their structure. However, making an interface that switches between these two states has proven challenging and concepts to date rely on changes in the physiochemical environment, which is static in biological systems. Here we present the first interface that can be electrically switched between a high‐capacity (>1 μg cm−2) multilayer protein binding state and a completely non‐fouling state (no detectable adsorption). Switching is possible over multiple cycles without any regeneration. Importantly, switching works even when the interface is in direct contact with biological fluids and a buffered environment. The technology offers many applications such as zero fouling on demand, patterning or separation of proteins as well as controlled release of biologics in a physiological environment, showing high potential for future drug delivery in vivo.

Interfaces functionalized with polymers are known for providing excellent resistance towards biomolecular adsorption and for their ability to bind high amounts of protein while preserving their structure. However, making an interface that switches between these two states has proven challenging and concepts to date rely on changes in the physiochemical environment, which is static in biological systems. Here we present the first interface that can be electrically switched between a high-capacity (> 1 μg cm À 2 ) multilayer protein binding state and a completely non-fouling state (no detectable adsorption). Switching is possible over multiple cycles without any regeneration. Importantly, switching works even when the interface is in direct contact with biological fluids and a buffered environment. The technology offers many applications such as zero fouling on demand, patterning or separation of proteins as well as controlled release of biologics in a physiological environment, showing high potential for future drug delivery in vivo.

<p>We present a polyelectrolyte brush electrode with high-capacity for protein immobilization that captures and releases proteins by an electrochemical potential. Central to our concept is the use of polyelectrolyte brushes that switch reversibly by electrochemistry. Our electrode enables high-fidelity control of protein species in space and time. We predict several application areas for this technology; for instance in protein separation and in biomedical devices.</p>

<p>We present a polyelectrolyte brush electrode with high-capacity for protein immobilization that captures and releases proteins by an electrochemical potential. Central to our concept is the use of polyelectrolyte brushes that switch reversibly by electrochemistry. Our electrode enables high-fidelity control of protein species in space and time. We predict several application areas for this technology; for instance in protein separation and in biomedical devices.</p>