What is the difference between Macroemulsion and microemulsion?
Microemulsions are thermodynamically stable systems, whereas macroemulsions are kinetically stable systems [2]. Also, microemulsions are translucent and of low viscosity, while macroemulsions are opaque and of relatively high viscosity.
What is micro and macro emulsion?
IUPAC definition. Emulsion in which the particles of the dispersed phase have diameters from approximately 1 to 100 μm. Note 1: Macro-emulsions comprise large droplets and thus are “unstable” in the sense that the droplets sediment or float, depending on the densities of the dispersed phase and dispersion medium.
What is microemulsions and explain how it differs from emulsions?
Another difference is that microemulsions are clear or translucent with droplet size in nanometers, while emulsions are coarse, milky dispersions with droplet size usually measured in micrometers. The use of microemulsions for the transdermal delivery of specific therapeutic agents is also described.
Why is microemulsion not a true emulsion?
In contrast to ordinary emulsions, microemulsions form upon simple mixing of the components and do not require the high shear conditions generally used in the formation of ordinary emulsions.
What is HLB number?
Hydrophilic–lipophilic balance (HLB) HLB represents the oil and water solubility of an emulsifier and is used to classify emulsifiers. The HLB number is usually on a scale of 0–20. Lower HLB values are an indication of high oil affinity.
What is emulsification agent?
An emulsifying agent (emulsifier) is a surface-active ingredient which adsorbs at the newly formed oil–water interface during emulsion preparation, and it protects the newly formed droplets against immediate recoalescence.
What are microemulsions used for?
Microemulsions have ultralow interfacial tension between the water phase and the oil phase. Water-in-oil microemulsions have been used to deliver water-soluble oilfield chemicals into subterranean rock formations.
What is nano emulsion technology?
Nanoemulsions are nano-sized emulsions, which are manufactured for improving the delivery of active pharmaceutical ingredients. These are the thermodynamically stable isotropic system in which two immiscible liquids are mixed to form a single phase by means of an emulsifying agent, i.e., surfactant and co-surfactant.
Why microemulsions are optically transparent?
A microemulsion is considered to be a thermodynamically or kinetically stable liquid dispersion of an oil phase and a water phase, in combination with a surfactant. Because the droplet size is less than 25% of the wavelength of visible light, microemulsions are transparent.
Why emulsifying agents are used?
emulsifying agents Substances that are soluble in both fat and water and enable fat to be uniformly dispersed in water as an emulsion. Emulsifying agents are also used in baking to aid the smooth incorporation of fat into the dough and to keep the crumb soft. …