Nanoparticles based on quaternary ammonium-chitosan conjugate: A vehicle for oral administration of antioxidants contained in red grapes

The purpose of this study was to demonstrate that nanoparticles (NP), obtained by ionotropic cross linking of reduced-MW chitosan (rCh) derivatives with reduced-MW hyaluronan (rHA), could be profitable vehicles for oral administration of beneficial doses of antioxidant constituents of red grape seeds extracts (GSE). NP have previously shown aptitude for internalisation by endothelial progenitor cells. Here they were seen by a fluorescence microscope migrating across excised rat intestine from mucosal to serosal side and permeating from the donor to the acceptor compartment of an Ussing chamber while carrying significant (15-20%) steadily associated fractions of initial antioxidant load. Freshly prepared NP dispersions were stabilised by lyophilisation. The NP dispersions were regenerated from the lyophilised products by adding water under gentle stirring. Lyophilisation-regeneration caused a significant NP size increase yet particles did not grow beyond the upper size limit of particles able to cross the intestinal barrier (500 nm).