Hydrogels have been prepared by the copolymerization
between N,N-dimethylacrylamide or N-isopropylacrylamide
with furfuryl methacrylate using N-4-(chlorocarbonyl)
phenyl maleimide or N-maleoyl-L-leucine, respectively,
coupled with polyethylene glycol to synthesize polymeric
dienophiles [24,25]. Poly(N-vinyl-2-pyrrolidone)-based
hydrogels were also prepared using N-alaninyl maleimide
[26] and dienophile-functionalized cyclodextrins were
cross-linked with furan-based isopropylacrylamide [27].
Recently, hyaluronic acid-based hydrogels preparations
by means of aqueous DA reaction between furan-modified
hyaluronic acid structures and either polyethylene glycol
based maleimides [15] or maleimide functionalized hyaluronic
acid have been reported [21].