Curcumin (CR) is a natural polyphenol with antioxidative, anti-inflammatory, and anticancer
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 CR with sulfobutylether-β-cyclodextrin (SBE-β-CD) was prepared in solution and
at the solid state using different preparation techniques and characterized by Fourier
transform infrared, nuclear magnetic resonance, differential scanning calorimetry,
scanning electron microscopy, phase solubility studies, and Job's plot method. Results
clearly indicate that CR 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 CR (from 0.56 to 102.78 μg/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 CR anticancer and antioxidant activity.