Cationic liposomes bind with nucleic acids such as plasmids and oligodeoxynucleotidles to form complexes known as lipoplexes. Although these lipoplexes have several advantages over other forms of nucleic acid transfer methods in cell culture and in-vivo, toxicity remains a problem, especially in-vivo. Nevertheless, these carriers have been used in clinical trials against cystic fibrosis and cancer and their usage is attributed mainly to their versatility, especially when it comes to the range of routes available for administration of nucleic-acid-based drugs in-vivo.