Interaction of taxol and other anticancer drugs with alpha-cyclodextrin

The interaction between 23 anticancer drugs and alpha-cyclodextrin (alpha-CD) was studied by reversed-phase charge-transfer thin-layer chromatography and the relative strength of interaction was calculated. As alpha-CD has smaller cavity than beta- and tau-CD it interacted only with 10 anticancer drugs proving the relatively poor complex forming capacity of alpha-CD. The hydrophobicity of host-guest inclusion complex was always different from that of the uncomplexed drug suggesting that the complex formation may influence the uptake, absorption, half-life etc. of the original drug. The inclusion forming capacity of drugs differed considerably according to their chemical structure. The intensity of interaction significantly depended on the hydrophobicity of the guest molecule proving the preponderant role of hydrophobic interactions in inclusion complex formation.