The conformation properties of clinically relevant hybrid macromolecular antioxidants (dextran
hydrophobically modified by sterically hindered phenols) in aqueous solution were characterized by
a combination of dynamic light scattering (DLS), size exclusion chromatography (SEC), and small-angle
neutron scattering (SANS). We were able to split and analyze separately two different types of polydispersity
—polydispersity over molecular weights and the one over substitution degree. The properties of the
hybrid macromolecules are determined by the number of hydrophobic antioxidants in a single molecule.
An insertion of hydrophobic groups into a hydrophilic chain changes the conformation of a single conjugate
macromolecule. We have established that with the increasing of a number of hydrophobic antioxidant
groups, a conformational transition occurs where a single conjugate undergoes a transition from a Gaussian
coil conformation to a more compact structure.