Polysaccharide micro/nanoparticles, incorporating stabilizers (natural antioxidants), prodegradingagents (such as enzymes or metal oxide nanoparticles) or other active ingredients,can be considered ideal chaperones to introduce various and heterogeneous substances intopolysaccharide films in virtue of their structural affinity. The possibility of obtainingbiodegradable and colloidally stable nanoparticles from xyloglucan has been hereinvestigated.Xyloglucans are a major class of structural polysaccharides found in the primary cell walls ofhigher plants. They are particularly interesting raw materials for their excellent film formingproperties, thermal stability and hydroxyl rich, highly branched molecular structure, whichcontrols hydrophobicity and solubility characteristics and, thereby, temperature or solventresponsiveness. If the branching degree and molecular weight are properly modified, stablexyloglucan nanoparticles dispersions can be obtained.During the first part of this CRP protocols for xyloglucan purification and dispersion in waterin the form of stable colloids have been developed. 60Co γ irradiation has been applied tomodify the molecular weight distribution of a partially degalactosylated xyloglucan variant.Aqueous dispersions of the irradiated materials have been characterized by both dynamic lightscattering measurements at different temperatures and gel filtration chromatography. Theaggregation kinetics at 37°C of nonirradiated and irradiated variants have been studied bydynamic light scattering measurements in order to confirm their temperature-responsivebehavior, when dispersed in water at low concentration. Chemical modification of xyloglucanwith nitrocinnamic acid has been performed in order to graft nitrocinnamate pendant groupsthrough an esterification reaction, thereby inducing reversible photocrosslinking. The successof the reaction has been confirmed through UV-vis and FTIR spectroscopies, whereas a morequantitative estimation of the derivatisation degree is undergoing.
|Number of pages||12|
|Publication status||Published - 2012|