Fig. 1

a Schematic sketch of the HPF molecule. The hydrophobic E and D domains consist of amino acids; whereas, its hydrophilic α chains at the outer ends are based on carboxyl groups. This structural combination allows a conformational change after the adoption on a material: b on hydrophobic surfaces, the hydrophobic domains D and E preferentially adsorb, which results in a stretched conformation. c The hydrophilic α chains are more attracted to hydrophilic surfaces. The chains interfold for the latter case in order to improve the connection, which leads to a rather globular structure