The formation of dynamic hydrazone bonds through the reaction of hydrazide-modified HA (ADH-HA) with both aldehyde-modified HA (HA-CHO) and aldehyde-modified CNCs (CNC-CHO), enabled covalent crosslinking of HA and the coupling of CNCs to the HA chains, resulting in hybrid hydrogels with reinforced mechanical properties well-suited for application in wound dressing, and in tissue engineering (Figure ). . For wound treatment, the structural stability of hydrogels and their ability to recover rapidly from damage are central in (Figure ). The loading of Dox into the nanogels and combretastatin-A4 phosphate (CA4P) in the dispersing matrix, resulted in a dual drug delivery system for synergistic local therapy. To be noted that in this case the particles had no impact on the material properties and its reinforcement was mediated by the presence of an additional crosslinker, namely a 4-arm-PEG-SH (4 wt%) capable to react with the oxidized polymer scaffold. Adapted with permission. Copyright 2018 American Chemical Society.