mPEG-CHO (MW 5000) is involved in the formation of three-dimensional porous scaffolds and acts as a delivery carrier when combined with active substances. The -CHO functional group interacts with the -NH2 group of chitosan chains, forming a glutaraldehyde-type adduct that functionalizes mPEG. This process of functionalization and crosslinking affects the rigidity of the delivery system, enabling the crosslinked conjugate system to possess slow release capabilities.