Cationic Lipid

Cationic lipids typically have a positively charged head group followed by a hydrophobic tail of varying composition. In an aqueous environment, these lipids form micelles with positively charged surfaces that complex with DNA. After interacting with nucleic acids, cationic liposomes form aggregated clusters of vesicles. These liposomes act to neutralize charge repulsion between cell membranes and DNA and promote endocytosis, similar to the mechanism of cationic polymers. The positive charge of phospholipids allows cationic liposomes to form complexes with negatively charged nucleic acids (DNA, mRNA, and siRNA) through ionic interactions. These interactions allow cationic liposomes to coagulate and encapsulate various therapeutic and diagnostic agents in their aqueous compartments or in their lipid bilayers.