Recent Advances in Cationic Nanoemulsions for Drug Delivery: Preparation, Properties, and Applications.

Nanoemulsions have gained popularity as drug delivery vehicles owing to the enhanced solubility of insoluble drugs, the augmented stability of photo- and thermosensitive substances, and the facilitation of transdermal permeation of efficacy substances. As the cell surfaces of the skin, cornea, gastrointestinal mucosa, and other cells in living organisms carry negative charges, cationic nanoemulsions (CNE) mainly promote drug absorption through electrostatic effects. In this review, a brief characterization of CNEs is provided, and the types of cationic agents and their roles in nanoemulsions, including cationic surfactants, cationic lipids, cationic polymers, cationized polysaccharides, and phytosphingosine (PS), are discussed.