One or more embodiments of the present invention provide a novel composition for gene delivery are directed to a group of polysaccharide polymers, having one or more nucleic acid delivery side chains comprising cationic peptides. In some embodiments, these cationic peptides condense and physically bond to one or more nucleic acids to form a polysaccharide-nucleic acid complex that permits delivery to and transfection of the nucleic acid(s) into cells. In some embodiments, the polysaccharide polymers of the present invention may also have one or more zwitterionic side chains and/or reactive side chains.