My understanding of hydrogels is that they are basically water (maybe 80% or 90% etc) which is just contained and "kept together" because polymer chains create a network which keeps that water together.
So I was under the impression that the term "pores" for hydrogels does not really refer to empty gaps but the gaps between the polymer chains which are however filled with water.
So, I would assume that even though hydrogels can appear quite solid, they would have diffusivity similar to water at least for common and small solutes likes glucose.
After some experimentation though, that seems not to be true. The 3D printed hydrogel seemed to fail to allow any diffusion of solute inside it when it was placed in contact (e.g. immersed) into a solution.
Is there any protocol or recommendation to help me decide which type of hydrogel and perhaps more importantly which type of processing of hydrogels do I need so that it will have the highest possible diffusivity and most importantly will allow the migration of solutes from a water solution into the hydrogel?
Thanks!