초록 |
The hydrogels are widely used for drug delivery. Their uses as a carrier depend on controlling the mechanical properties. However, conventional strategies to increase the stiffness lead to decrease in the toughness and subsequently limit the releasing of encapsulated materials. To solve this limitation, we hypothesized that the functional cross-linker composed of chemically cross-linking units and physically assembling moieties would improve the toughness while keeping on increasing the stiffness. First, the bio-inspired oligo(L-valine)-based cross-linker, acrylated poly(ethylene glycol)-b-oligo(L-valine) was successfully synthesized to form micelle-like self-assemblies in an aqueous solution. Then, the gel was examined by varying of molecular weights and their concentrations. The underlying mechanism to decouple the inversed dependency of toughness on the stiffness would be explained by the reversible cross-links of β-sheets in response to applied mechanical force. |