Micellar Solubilization of Carbamazepine

Aims: An important property of micelles with particular significance in pharmacy is their ability to increase the solubility of poorly soluble drugs in water thus increasing their bioavailability. It was of interest to increase the solubility of carbamazepine (CBZ) in aqueous media. Therefore, solubilization of carbamazepine (CBZ) in variety of surfactants was investigated.
Study Design: In this work the solubilization of carbamazepine (CBZ) was studied in micellar solutions of different anionic and cationic surfactants.
Place and Duration of Study: Department of Chemistry, University in Tuzla, between
January 2012 and June 2012.
Methodology: The solubilization data were analyzed on the basis of a pseudo-phase model. An ultraviolet–visible spectrophotometry was used to analyze carbamazepine solubility and its molecular location in the micelles.
Results: It was found that carbamazepine solubility increases due to an increase in the carbon length of cationic surfactants. This indicates that carbamazepine is solubilized primarily in the hydrophobic micellar core. Of all surfactants used, the one that gives the highest solubilization of carbamazepine is SDS with value of molar solubilization capacity 0.163 and the lowest is DTAB and SDBS with value of molar solubilization capacity 0.090 nad 0.092.
Conclusion: The results confirm that SDS micelles can solubilize carbamazepine and significantly increase its total aqueous solubility. The solubility of carbamazepine is present only at a concentration of surfactants exceeding the critical micellar concentration (cmc).