Very long-chain fatty tails for enhanced transfection.

The long chain saturated fatty acids, arachidic (C20) and lignoceric (C24), are found as components of phospholipids within mammalian cellular membranes. Although these lipids have rarely been used as components of transfection reagents, we recently demonstrated that elongation of the fatty tail beyond C18 provide a means of increasing the transfection efficiency of cationic lipids. To investigate this effect further, a new library of single-chained cationic lipids consisting of mono-, di- or tri-arginine residues, a range of amino acid spacers and these long-chain saturated fatty tails were synthesised using an Fmoc solid-phase strategy, which allowed the preparation of 18 compounds, some with remarkable transfection abilities.