Abstract: The present invention relates to a drug delivery system and methods of using the delivery system, particularly a delivery system for transporting pharmaceutically active agents across, for example, the skin, the surface of the eye or mucosal membranes. The drug delivery system comprises a pharmaceutically effective moiety and a polyamine or amine moiety, wherein the polyamine or amine moiety does not comprise two or more contiguous basic amino acid residues. The drug delivery system may be provided for use as a medicament, or for use in the treatment of a disease or condition selected from eye disease, burns, infection, and trauma. The invention also provides a method comprising administering a pharmaceutically effective amount of the drug delivery system of the invention to a patient in need thereof.