Abstract: A biodegradable particulate vector for transporting biologically active molecules is prepared containing a nucleus formed of a cross-linked polysaccharide or oligosaccharide matrix having grafted ionic ligands, a layer of fatty acid compounds covalently bonded to the nucleus and a layer of phospholipids hydrophobically bonded to the layer of fatty acid compounds. Dextran, cellulose or starch may be cross-linked with epichlorohydrin to form a cross-linked polysaccharide matrix. Ionic ligands may be grafted using an acidic compound such as succinic acid, phosphoric acid or phosphorous oxychloride, or a basic compound such as choline, hydroxycholine, 2-(dimethylamino)ethanol or 2-(dimethylamino) ethylamine fastened onto the grafted acidic compound. Phosphoric acid or phosphorous oxychloride in one step provide both cross-linking and ionic ligands. Co-cross-linking can be obtained using a protein such as keratin, collagen or elastase.

Abstract: A biodegradable particulate vector for transporting biologically active molecules is prepared containing a nucleus for containing a biologically active molecule, a first layer of fatty acid compounds covalently bonded to the nucleus and a second layer of phospholipids hydrophobically bonded to the first layer. The nucleus is between 10 nm and 10 .mu.m in size and is formed of a cross-linked polysaccharide or oligosaccharide matrix onto which ionic ligands are uniformly grafted. The cross-linked polysaccharide may be dextran, cellulose or starch cross-linked with epichlorohydrin. The ligand may be an acidic compound selected from succinic acid, phosphoric acid, citric acid, glycine, alanine, glutamic acid and aspartic acid, or a basic compound such as choline, hydroxycholine, 2-(dimethylamino)ethanol or 2-(dimethylamino)ethylamine fastened onto the matrix via the acidic compound. The polysaccharide or oligosaccharide may be co-cross-linked with a protein such as keratin/collagen or elastase.