A new complex of curcumin with sulfobutylether-β-cyclodextrin: characterization studies and in vitro evaluation of cytotoxic and antioxidant activity on HepG-2 cells

Curcumin is a natural polyphenol with anti-oxidative, anti-inflammatory and anti-cancer properties but its therapeutic potential is substantially hindered by the rather low water solubility and bioavailability. Thus, in this work, a new soluble inclusion complex of curcumin with sulfobutylether--cyclodextrin (SBE-β-CD) was prepared in solution and at the solid state using different preparation techniques and characterized by FT-IR, NMR, DSC, SEM, phase solubility studies and Job’s plot method. Results clearly indicate that curcumin reacts with SBE-β-CD to form a host-guest complex with an apparent formation constant of 1455 M-1. Moreover, SBE-β-CD strongly increases water solubility of curcumin (from 0.56 to 102.78 g/ml, at 25◦C) and lyophilization method seems to be the best preparation technique to obtain the complex at the solid state. Finally, an in vitro test on a human hepatic cancer cell line (HepG-2) shows that complexation positively influences curcumin anticancer and antioxidant activity