Microemulsion as drug and gene delivery vehicle: An inside story

Abstract

Microemulsions (MEs, water-in-oil or oil-in-water) are the isotropic mixtures of two immiscible liquids, that is, the aqueous phase (water with or without hydrophilic drug) and an organic phase (oil with or without lipophilic drug) with emulsifying agents (surfactant/cosurfactant). Numerous studies suggest that MEs guard labile drug, upsurge the solubility of drugs, sustain the discharge of the active moieties, and enhance the bioavailability of active molecules. In addition, owing to their exceptional properties, namely, great interfacial area, ultralow interfacial tension, the capability to solubilize large extent of insoluble drugs, and thermodynamic stability, it has been developed and exploited in the treatment of many illnesses via several routes. MEs are widely utilized for effective delivery of several active moieties, for example, acyclovir, chloramphenicol, diazepam, fluconazole, via the topical route in pharmaceutical fields. MEs for skin use permit quick dissemination of drug molecules owing to the great exposure of the continuous phase with the outer layer of the skin. Further other additives diminish the hindrance effect of the stratum corneum. This chapter covers several ways (i.e., oral, intravenous, transdermal/topical, nasal, ophthalmic, targeted drug delivery, gene delivery) through which MEs have been delivered to treat various illness. © 2019 Copyright © 2019 Elsevier Inc. All rights reserved..