Positively charged microemulsions of dexamethasone: comparative effects of two cosurfactants on ocular drug delivery and bioavailability.
BACKGROUND
The objective of this investigation was to evaluate the potential of mucoadhesive chitosan-coated positively charged microemulsions (CH-MEs) of dexamethasone with respect to the change in nonionic cosurfactants.


METHODS
CH-MEs were prepared with different concentrations of surfactant and cosurfactant using the water titration method and coated with low-molecular-weight chitosan.


RESULTS
All formulations displayed an average globule size between 85 and 187 nm and a positive surface charge. The optimized CH-MEs showed greater penetration of dexamethasone in the anterior segment of the eye, resulting in twofold and fourfold higher dexamethasone concentration than uncoated ME and drug suspension, respectively.


CONCLUSIONS
The developed CH-MEs shows increases in ocular penetration and bioavailability.
Department of Pharmaceutics, Indian Institute of Technology, Banaras Hindu University, Varanasi-221005 UP, India.
Karthikeyan
K
Kesavan
Jayanta Kumar
JK
Pandit
Shri
S
Kant
Madaswamy Sona
MS
Muthu