Nanoemulsions as medicinal components in insoluble medicines

Abstract

Background: Medicine’s success relies on solubility, which is the process of dissolving a solid substance in a fluid phase to create a uniform molecular dispersion. However, hydrophobic active medicinal components exhibit poor solubility in water, limiting their effectiveness and incorporation into medications. Aim: This review explores the potential of nanoemulsions as a solution for delivering hydrophobic medicinal components with low solubility. The study investigates the benefits of nanoemulsions, including enhanced absorption, effective targeting, controlled release, and protection of encapsulated bioactive ingredients. Materials and methods: Nanoemulsions are formulated by combining two immiscible liquids with emulsifying agents within a thermodynamically stable colloidal dispersion system. The review categorizes various preparation techniques into high-energy and low-energy spontaneous emulsification methods. The choice of preparation procedures and materials used significantly affects the stability of nanoemulsions over time. Evaluation of nanoemulsions includes studying medication release in vitro, in vitro permeation, stability and thermodynamic stability, shelf life, viscosity, interfacial tension, pH, and osmolarity. Results: Nanoemulsions, such as Celecoxib (Phase Inversion), acetylsalicylic acid (Ultrasonication), and Flurbiprofen (Homogenization and Ultrasonication), offer distinct advantages for medications with low solubility compared to conventional emulsions. These nanoemulsions comprise small droplets with a larger surface area, promoting enhanced absorption. They demonstrate effective targeting, controlled release, and protection of encapsulated bioactive ingredients. Moreover, the diminutive droplet sizes of nanoemulsions contribute to their reduced susceptibility to issues like flocculation, coalescence, sedimentation, or creaming. Conclusion: Nanoemulsions hold great promise in overcoming the solubility limitations of hydrophobic medicinal components. They provide enhanced absorption, effective targeting, controlled release, and protection of bioactive ingredients. The choice of preparation techniques and materials plays a crucial role in ensuring the stability of nanoemulsions over time. Further studies are warranted to optimize their use and explore their potential applications in drug delivery systems.