Sclerotium rolfsii scleroglucan: The promising behavior of a natural polysaccharide as a drug delivery vehicle, suspension stabilizer and emulsifier

VIÑARTA S.C.; FRANÇOIS N.J.; DARAIO M.E.; FIGUEROA L.I.C.; FARIÑA J.I.

INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES

ELSEVIER

Lugar: Netherlands; Año: 2007 vol. 41 p. 314 - 323

0141-8130

Gel matrices of scleroglucans from Sclerotium rolfsii ATCC 201126 (EPS I and EPS II, from 48-h and 72-h fermentations, respectively) wereevaluated on their release kinetics of theophylline (Th). Equivalent polymer (2%, w/w) and Th (0.2%, w/w) concentrations showed almost coincident drug release patterns, independently of polymer molecular weight or the microstructural properties of gel matrices. Dynamic rheological studies of scleroglucan hydrogel structures (storage, G_, and loss, G__, moduli) indicated a solid-like behavior. Differences on pore size dimensions (EPS I = 20_m and EPS II = 7_m) were in accordance to the differences in G_ (EPS I = 113 Pa and EPS II = 161 Pa), a fact likely related to variations in the cross-linking density of polymer networks. Compared to already known biopolymers, EPS I and EPS II at 0.5 g/L showed a good dispersing ability against particulate suspensions of activated charcoal, bentonite, CaCO3, celite and quartz powder. Emulsifying ability of both EPSs at 2 g/L was high (E = 56?60%) when tested with kerosene, moderate (∼30%) with hexadecane, and negligible in the presence of olive oil-in-water emulsions.