ABSTRACT
A nanoemulsion is a multiphase colloidal dispersion and is characterized by stability and clarity. A marginal difference between nanoemulsions and microemulsions exists as a micellar phase or mesophase. Microemulsions are formed through thermodynamic self-assembly, whereas nanoemulsions require an external shear for rupturing the droplets. Microemulsions are not emulsions of microscale droplets as they are formed by a self- assembled equation phase where the surface tension does not play a significant role. Nanoemulsions underline the basic principle in microemulsion formulation. Nanoemulsions have a smaller particle size and are most effectively produced using high-pressure equipment. The most commonly used methods for producing nanoemulsions are high-pressure homogenization and microfluidization, used on both laboratory scale and industrial scale. Methods like ultrasonication and in situ emulsification are also suitable for the preparation of nanoemulsions. The homogenizing pressure for developing nanoemulsions is important to induce adhesive forces around the chosen chemical entity like magnetic nanoparticles capped with citric acid.
