Biocompatible elastin-like click gels: design, synthesis and characterization.

Elastin-like recombinamer click gels (ELR-CGs) for biomedical applications, such as drug delivery or tissue engineering, have been developed by taking advantage of the click reaction (CuAAC) in the absence of traditional crosslinking agents. ELRs are functionalized with alkyne and azide groups using conventional chemical techniques to introduce the reactivity required to carry out the 1,3-dipolar cycloaddition under mild biocompatible conditions, with no toxic by-products and in short reaction times. Hydrogels with moduli in the range 1,000-10,000 Pa have been synthesized, characterized, and tested in vitro against several cell types. The cells embedded into ELR-CGs possessed high viability and proliferation rate. The mechanical properties, porosity and swelling of the resulting ELR-CGs can easily be tuned by adjusting the ELR concentration. We also show that it is possible to replicate different patterns on the hydrogel surface, thus allowing the use of this type of hydrogel to improve applications that require cell guidance or even differentiation depending on the surface topography.