mPEG-CHO (MW 350) participates in the formation of three-dimensional porous scaffolds and acts as a delivery vehicle by carrying active substances. The -CHO functional group interacts with the -NH2 functional group of the chitosan chain to form a glutaraldehyde-type adduct, functionalizing mPEG. This functionalization and cross-linking can affect the rigidity of the delivery system, enabling the cross-linked conjugated system to have a slow-release function.