Development and characterization of dexamethasone mesylate anchored on multi walled carbon nanotubes

Dexamethasone conjugated multi wall carbon nanotubes (DEX-MWCNTs) were developed for controlled delivery of a doxorubicin HCl (DOX) with reduced toxicity. The DEX-MWCNTs were prepared by sequential functionalization of MWCNTs. The DOX was physically loaded onto the purified raw MWCNTs and DEX-MWCNTs at pH 7.4 phosphate buffer solutions (PBS) and evaluated for entrapment efficiency, in vitro release, hemolytic toxicity and ex vivo studies on A-549 lung epithelial cancer cell line. DOX was efficiently loaded into purified raw and DEX-MWCNTs formulation and the highest entrapment of DOX was found to be 92.6 +/- 0.5% in the case of DEX-MWCNTS with good dispersion. In-vitro release of DOX was studied from the DOX/DEX-MWCNTs at pH 5.5 and 7.4 (PBS), which displayed an initial faster followed by sustained release up to 200 h. Further, DOX/DEX-MWCNTs were found to be less hemolytic and more cytotoxic as compared to free DOX on A-549 lung epithelial cancer cell line.