A crosslinked system from scleroglucan derivative: preparation and characterization

Matrices obtained by a crosslinking reaction between the polycarboxylated derivative of scleroglucan (sclerox) and 1,6-hexanedibromide have been prepared and characterized. Different ratios between the alkane dihalide and sclerox yielded products with different properties. Water uptake by the hydrogel with a low degree of crosslinking was remarkably affected by ionic strength. The determination of the crosslink density is led by simultaneously solving two Flory equilibrium equations referring to two different conditions characterized by the presence or the absence of a salt in the swelling agent. Moreover, the swelling kinetics was studied by means of a recently proposed model. Finally, the permeation of two model molecules (theophylline and polystyrene sulphonate-sodium salt) through the hydrogels was evaluated.