Interestingly, high crosslinked networks can exhibit a higher swelling ratio compared to their NP-free counterpart, which can be attributed to an enhanced 3D network facilitating the retention of water. Water uptake can also be promoted by increased osmotic pressure due to metal oxide NPs (e.g., CuO ) the formation of larger pores and spaces. The latter may arise from reduction of the crosslinking degree as observed with PEDOT NPs in a HA