The chemical structure of lactobionic acidcontains a galactose unit and a gluconic acid unit linked by etherlinkage. The carboxyl group of gluconic acid unit reacts with theamino group of chitosan to form an amide linkage. The lactobionicacid grafted chitosan demonstrated higher transfection efficiencythan ligand-free chitosan (45.3% vs 19.8%) in ASGPR overexpressedHepG2 cells