SAINT-2 is a cationic lipid with gene transfection activity and is a pyridinium lipid analog. It forms molecular membranes that interact with plasmids, creating lipid complexes. Once these complexes are taken up by cells, the plasmid dissociates from the lipid complex due to the action of DOPE, facilitating translocation across the endosomal and/or nuclear membranes. This process efficiently transfers small oligonucleotides into cells.