Complexation behavior of antiestrogen drug tamoxifen citrate with natural and modified β-cyclodextrins

Inclusion complexes of the poorly-soluble antiestrogen drug tamoxifen citrate (TMX) were prepared with beta-cyclodextrin (beta-CD) and 2,3-di-O-hexanoyl-beta-cyclodextrin (beta-CDC6) being natural and amphiphilic cyclodextrins, respectively using the co-lyophilization technique. Complexation occurred in aqueous medium for natural cyclodextrin beta-CD and a medium of water:ethanol mixture for the amphiphilic cyclodextrin beta-CDC6. The complexes were characterized using analytical techniques including Differential Scanning Calorimetry (DSC), Fourier Transform Infrared spectroscopy (FTIR) and proton Nuclear Magnetic Resonance Spectrometry (H-1 NMR). Anticancer efficacies of the complexes were determined against MCF-7 human breast carcinoma cell line with MTT assay. It was found that tamoxifen citrate can be incorporated in the cavity for beta-CD and both in the cavity and the aliphatic chains for beta-CDC6. The latter having two hydrophobic sites for inclusion of water-insoluble drug exhibited significantly higher anticancer efficacy accordingly.