Preparation of spherical porous hydrogel beads based on ion-crosslinked gum tragacanth and graphene oxide: Study of drug delivery behavior.

In this study, new spherical pH-sensitive porous hydrogel beads were prepared based on the water-soluble gum tragacanth (GT) polysaccharide and graphene oxide (GO) nanosheets by using Ca+2 and Ba+2 ions as crosslink agents, calcium carbonate particles as solid porogen, and Rivastigmine (RIV) as a model drug. The prepared hydrogel beads were characterized by FE-SEM, XRD, FTIR, BET, and TGA techniques. The swelling behavior of the beads was affected by cross-linker content, type of cross-linker, composition of beads, and pH. These hydrogel beads exhibited well pH-sensitivity during drug release investigation under simulated gastric (<45% at pH 1.2) and intestinal (∼97% at pH 7.4) media. The cytotoxicity test was performed on human fibroblast cells using MTT assay. The results indicated that cell survival rate was more than 98% in <125 μg/mL beads concentration. Incorporating of GO in the hydrogel increased the swelling capacity, entrapment efficiency, and ensuring a controlled release of the entrapped drug.