Scleroglucan and guar gum. The synergistic effects of a new polysaccharide system

Scleroglucan (Sclg) and guar gum (GG) are capable of giving gels in the presence of borax. This study focuses on how a mixed system of the two polysaccharides can be affected by the addition of borax. The anisotropic swelling behavior of tablets obtained by compression of the freeze-dried new gel system is also investigated and compared to that of Sclg and GG alone. Rheological characterization evidences a synergistic effect in terms of critical time, mesh size, as well as cross-linking density. Also creep recovery experiments, carried out in the presence of borax, show a synergistic effect: when the polymers are mixed, quite low compliance was estimated in comparison to that of Sclg and GG. On the other side, the flexible chains of GG induce the self-healing properties of the mixed gel system since the rigid, triple helix of Sclg does not show such peculiar characteristics. The deep insight into the physico-chemical properties of the new hydrogel system can play a fundamental role in optimizing its practical application (e.g., in drug delivery, cosmetic products, human tissue repair, wound dressing, and food staff).