Microemulsions as a potential carrier for improved drug delivery

Abstract

Microemulsions are thermodynamically stable colloidal dispersions formed in an oil-water environment with the help of surfactants. They are transparent or translucent, isotropic, and have a small droplet size, typically 10 to 100 nanometers. In the pharmaceutical industry, microemulsions are often used to enhance the solubility of poorly soluble drugs. Many drugs have low aqueous solubility, leading to poor bioavailability and reduced therapeutic efficacy. However, when formulated as microemulsions, these drugs can be solubilized in the oil-water interface of the microemulsion system, resulting in a significant increase in their apparent solubility. The small droplet size and large interfacial area of microemulsions provide an ideal environment for incorporating hydrophobic drugs, as the drug molecules can be accommodated in the hydrophobic core of the micelles or droplets. This solubilization makes the drug more readily available for absorption in the body, thereby improving its bioavailability. As thermodynamically stable colloidal dispersions, microemulsions have gained significant attention due to their unique properties and versatile applications. This review paper aims to provide a comprehensive overview of microemulsions with respect to its patentability arena, delving into nuanced aspects that have not been extensively covered in prior review articles. We address key unanswered questions in the existing literature, offering fresh perspectives and insights. Our analysis encompasses the latest advancements in microemulsion research, highlighting novel applications, formulation strategies, emerging trends, market potential of microemulsion as well as its future scope in the pharmaceutical industry.

Keywords

• Microemulsion
• Ternary phase
• solubilization
• applications
• co-solvents

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