L-Dierucoyl Lecithin-D9 is a labelled analogue of L-Dierucoyl Lecithin (D441945). L-Dierucoyl Lecithin is a phospholipid that is used in the formation of netural lipid bilayer membranes for the purposes of research and experimentation in the fields of biology and biochemistry. L-Dierucoyl Lecithin is a derivative of Lecithin, a phospholipid that is an important component of naturally occurring, biological membranes.