Self-aggregates of hydrophobized polysaccharides in water. Formation and characteristics of nanoparticles

Solution properties in water of hydrophobized pullulan containing 1.6 cholesterol groups per 100 glucose units (CHP-55-1.6) were studied. SEC measurements show that CHP (1.0 mg/mL, 0.10 wt %) intermolecularly aggregates and provides relatively monodispersive particles upon ultrasonication. Spherical particles with relatively uniform size (the diameter, 25±5 nm) were observed in the negatively stained electron microscopy of the aqueous CHP solution. The hydrodynamic radius of the CHP self-aggregate was approximately 13 nm and the aggregation number was approximately 13.