초록 |
In biological systems, responsive materials are ubiquitous in the form of viscoelastic colloid/polymer composite. While new materials inspired by these composites may advance bio-related technologies, experimental study remains in its infancy. Here, we present the thermo-responsive colloid/biopolymer hydrogels capable of 3 times modulus switch upon heating and cooling. Non-responsive colloids were first integrated into fibrin biopolymer hydrogels, and the rheological properties were investigated. Fibrin exhibits non-linear stiffening after colloids are introduced. Our interest was extended to responsive composites. The poly(N-isopropylacrylamide) (PNIPAM) microgels were fabricated and incorporated into fibrin to produce thermo-responsive composites. As the temperature passes through the low critical solution temperature of PNIPAM, we observe huge yet reversible changes in spatial organization and dynamic mechanical property, which was attributed to thermally-induced fibrin stiffening. |