(573h) Tuning Thermo Responsive Behavior and Rheological Properties of Cranberry Oligosaccharide Hydrogels

Cranberry is a popular functional food whose best known benefit has been promotion of urinary tract health. Cranberry oligosaccharides have shown effects on bacterial adhesion and biofilm formation. Futhermore, bioactive cranberry constituents containing phenolic compounds like flavanols and proanthocyanidins have known to associate with complex carbohydrates in solution. This makes cranberry oligosaccharides a suitable candidate for synthesizing hydrogels for delivering cranberry bioactive compounds for biomedical and pharmaceutical applications. Understanding the structure, gelation time and mechanical properties of such hydrogels will enable us to engineer effective drug delivery systems.

Here, we present a non-enzymatic gelation study of cranberry oligosaccharide using alcohols. These hydrogels are reversibly thermoresponsive and their mechanical properties can be adjusted by tailoring the synthesis stoichiometry. Both hydrophilic and hydrophobic interactions are believed to affect the solution state conformations. Observing rheological proeprties during gelation leads to insights into the microstructure of the gel. DLS and rheological measurements were utilized to study the influence of concentration, temperature and ionic strength on gelation behavior. Oscillatory rheology measurements confirmed the shear thinning behavior of the hydrogel. Evolution and crossover of storage modulus (G’) and loss modulus (G”) with temperature was studied for different concentration of hydrogels to determine gelation temperature for each of these systems. This study provides a novel insight into controlling gelation behavior and mechanical properties of cranberry oligosaccharide hydrogels