A SCIENTIFIC REVIEW ON NANOEMULSION FOR TARGETING DRUG DELIVERY SYSTEM

Nanoemulsions have attracted great attention in research, dosage form design, and pharmacotherapy. This is as a result of some attributes peculiar to nanoemulsions such as optical clarity, ease of preparation, thermodynamic stability and increased surface area. Poor water solubility remains the main culprit for the formulation scientist which can be overcome by canonization. Nanoemulsion is a kinetically stable and isotropic system of two immiscible liquids in the submicron size range. Nanoemulsions are composed of oil droplets dispersed in an aqueous medium and stabilized by surfactant molecules. Many parenteral nutrition and drug emulsions on the market confirm the safe use of NE over the years. Parenteral emulsions loaded with APIs (active pharmaceutical ingredients) are considered as drug delivery systems (DDS). DDS focuses on the regulation of the in-vivo dynamics, such as absorption, distribution, metabolism, and extended bioavailability, thereby improving the effectiveness and the safety of the drugs. Nanoemulsion is the thermodynamically stable isotropic system in which two immiscible liquid (water and oil) are mixed to form a single phase using an appropriate surfactant or its mix with a droplet diameter approximately in the range of 0.5-100 µm. Nanoemulsion droplet sizes fall typically in the range of 20-200 nm and show narrow size distributions. Problems such as creaming, coalescence sedimentation, and flocculation are not a concern for nanoemulsions due to their small droplet size. A comprehensive review is presented to give basic ideas about nanoemulsions, their preparation methods, and stability aspects. In this review, the attention is focused on giving brief regarding nanoemulsion formulation aspect, a method of preparation, characterization techniques with special emphasis on various applications and explains the components required, low and high energy processes involved in the preparation of nanoemulsions. This review sheds light on the current state of nanoemulsions in the delivery of drugs and other bio-actives. The morphology, formulation, characteristics, and characterization of nanoemulsions were also addressed.