Supramolecular hydrogels with tuned mechanical properties for tissue engineering

Hydrogels have been studied extensively for many tissue engineering applications. Nowadays, it is well established that their mechanical properties together with the chemical composition influence tremendously both cellular and tissue compatibility.[1] However, tailoring these hydrogel properties is not a straightforward task as changes in chemical composition often result in altered mechanical properties. Herein, we report on a strategy that uses short amphiphiles to obtain supramolecular hydrogels with tuned properties. In this strategy the chemistry of the gel is determined by the structure of the amphiphile(s), while its mechanical properties are tailored by adjusting the amphiphile(s) concentration.[2] Noteworthy, these network structures are assembled under mild often physiological conditions and have the inherent ability to respond to external stimuli, such as pH, temperature, as they are assembled via weak and reversible non-covalent interactions.[3, 4] Moreover, they are highly hydrated and present nanofibril structure, which is of a similar scale to the native extracellular matrix.[5]

Our results demonstrated that by tuning the chemistry of the amphiphile we can influence the directional assembly, i.e. we can obtain nanofibers with different length. We further show that under physiological conditions (cell culture medium) the nanofibers with different sizes form gels with different mechanical properties and altered stability. Finally, these gels are compatible with different cells, e.g. adipose-derived stem cells, bone marrow stem cells, ATDC5.