An arginine-grafted bioreducible poly(disulfide amine) (“ABP”) as a reagent for efficient and nontoxic gene delivery is described. ABP forms positively charged nano-particles of less than 200 nm with plasmid DNA. ABP is biodegraded under reducing conditions, such as the cytoplasm. ABP exhibits much higher transfection efficiency than polyethyleneimine in mammalian cells and exhibits no cytotoxicity.
