Nanoemulsion: A Potential Carrier for Topical Drug Delivery

Nanoemulsions (NEs) are stable nanocarrier systems consisting mainly of oil and water, which are stabilized by surfactant with cosurfactant. Due to their typical size, nano-emulsions are transparent or translucent, and minute droplet size makes them stable against sedimentation or creaming. The nanoemulsion system may be in the form of oil-in-water (O/W) or water-in-oil (W/O). The recent literature revealed that NEs as a colloidal carrier system has been confirmed to be a valuable strategy to improve the bioavailability of topically applied drugs. NE has been proposed as a viable alternative to conventional topical dosage forms due to the ability to overcome the skin/ocular barriers faced after administration. Better permeation rate, improved therapeutic efficacy and reduction of dose, non–specific toxicity, and targeted drug delivery system can improve drug effectiveness when drugs are incorporated into NEs. In recent years, research studies have focused more on ion nanoemulsion systems using a mixture of surfactants to solve critical factors, such as solubility, stability, and drug delivery applications. This chapter outlines the recent development in nanoemulsion as a delivery system to study topical drug delivery.