In order to provide expressions for the different terms in Eq. ( ), we restrict our model to a mean-field approximation, where the microions are modelled as non-interacting charged ideal gasses, neglecting intermicroion correlations. Furthermore, the suspension is described by means of cell model approximation: we consider a single microgel located at the center of a spherical cell, whose radius is determined by the microgel concentration, fulfilling electroneutrality.