STRUCTURAL CHARACTERIZATION (SHAPE AND DIMENSIONS) AND STABILITY OF POLYSACCHARIDE LIPID NANOPARTICLES/

The structure of a new supramolecular drug carrier (named Biovectors-B V) was studied using light scattering and scanning electronic microsco py techniques. This system consists of a polysaccharide core of chemic ally cross-linked maltodextrins to which phospholipids (and, in some c ases, cholesterol) are added. Both polysaccharide cores and BV crossli nked with phosphate (negatively charged) and epichlorhydrin (no net ch arge) are spherical particles. The increase in the ionic strength of t he medium increases the density of the charged polysaccharide cores. T he lipid strongly interacts with neutral and negatively charged cores, decreasing both intra- and interparticle interactions. The results (m ainly, rho = R(g)/R(h) < 0.775 in some cases) suggest that BV are gel- like particles of variable variable density, referred to as microgels or soft spheres. Neutral polysaccharides have a strong tendency to sel f-aggregate. This self-aggregation of polysaccharide neutral cores is prevented by the addition of lipid or dimethylsulfoxide. (C) 1997 John Wiley & Sons, Inc.