The importance of hydrogels in the biomedical and biotechnological
fields induced researchers to experimentally and theoretically
study their properties. Among them, one of the most important
is represented by the mesh size distribution of their polymeric
network. Indeed, this characteristic heavily rules the mass exchange
processes between the hydrogel and the surrounding. The aim of
this chapter is to present and discuss some techniques devoted to
the estimation of the polymeric network mesh size. In particular, attention
will be focused on rheology, low-field NMR, crioporosimetry,
and release tests.
