Invasomes A Novel Drug Delivery for Transdermal Drug Delivery System

Invasomes are a novel class of elastic phospholipid vesicles designed to enhance the percutaneous penetration of drugs, offering an improved alternative to conventional liposomes. These vesicles are composed of phosphatidylcholine, ethanol, and a variety of terpenes, which are known to significantly enhance skin penetration. Terpenes, such as citral, limonene, and cineole, disrupt the stratum corneum lipids, interact with intracellular proteins, and improve the partitioning of drugs into the skin, facilitating better drug absorption. Ethanol further enhances the vesicle's ability to penetrate the skin by providing a net negative surface charge and preventing vesicle aggregation through electrostatic repulsion. This synergistic effect between ethanol and terpenes significantly enhances the percutaneous absorption of both hydrophilic and lipophilic drugs. Moreover, the low irritancy of terpenes at concentrations between 1-5% makes them clinically acceptable penetration enhancers. This review discusses the composition, preparation methods, physicochemical characteristics, stability, and pharmaceutical applications of invasomes, highlighting their potential as an effective and non-invasive drug delivery system.