Microemulsions parenteral drug delivery

Microemulsions, and Lipid-Based Drug Delivery Systems for Drug Solubilization and Delivery—Part I Parenteral Applications... 

The production of microemulsions is comparatively simple and cost-effective, and thus, they have attracted a great interest as drug-delivery vehicles. Microemulsions have the capability of transporting lipophilic substances through an aqueous medium, and can also carry hydrophilic substances across lipoidal medium. Based on this attribute, potential of microemulsions has been explored for oral, transdermal, parenteral, topical, and pulmonary administration of lipophilic and hydrophilic drugs. In the last decade, microemulsions have also been explored for their potential as vehicles for topical ocular drug delivery."- ... 

Apart from the already established formulations, researchers are trying to develop novel oil-based formulations to combat the poor solubility and bioavailablity of NCE. Shevachman et al. developed novel U-type microemulsions to improve the percutaneous permeability of diclofenac. Shah et al.2 2 used microwave heating for the preparation of solid lipid nanoparticles by microemulsion techniques, which resulted in improved particle characteristics. Ki et al. reported sustained-release liquid crystal of injectable leuprolide using sorbitan monooleate. Recently, various novel oil-based drug delivery technologies are reported, which includes tocol emulsions, solid lipid nanopar-ticles, nanosuspensions, Upid microbubbles, sterically stabilized phospholipid micelles, and environmentally responsive drug delivery systems for parenteral administration.25 259... 

Micellar solutions and microemulsions are also used for parenteral delivery of hydrophobic drugs. They are usually stabilized by large amounts of hydrophilic surfactants, such as bile salts and polysorbates. Owing to their small size, micelles are less readily recognized by the immune system, resulting in prolonged circulation [36]. An example of micellar formulation is Taxol , in which the active antitumor agent paclitaxel is solubilized in micelles of polyoxyl castor oil. 

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