Multi-responsive physical gels formed by a biosynthetic asymmetric triblock protein polymer and a polyanion

We report the design, production and characterization of a biosynthetic asymmetric triblock copolymer which consists of one collagen-like and one cationic block spaced by a hydrophilic random coiled block. The polymer associates into micelles when a polyanion is added due to the electrostatic interaction between the cationic block and the polyanion. The collagen-like block self-assembles into thermo-responsive triple helices upon cooling. When both end blocks are induced to self-assemble, a physical gel is formed via thermo-responsive association of the charge-driven micelles. The self-assembly of both end blocks and the effects of salt and temperature thereon were characterized by light scattering and rheology.