Liposomes are extensively used to study the interaction of proteins, peptides and other molecules with the surface of a lipid membrane. One of the parameters that affects this interaction is the charge of the liposomal membrane. Phosphatidylserine (PS) is a negatively charged molecule. The amount of the negative zeta potential in the liposomes depends on the molar percentage of the phosphatidylserine (PS) in the formulation. Anionic Cellsome®-Phosphatidylserine (PS) catalog contains the products made from 0.5 up to 100 percent DOPS with various amount of negative zeta potentials. The matrix lipid DOPC that is used in the formulations does not significantly contribute to the charge of the liposomes. Anionic liposomes are used in blood complement studies and various types of in vitro studies.
