Nanoemulsion: A new medium to study the interactions and stability of curcumin with bovine serum albumin

Phospholipid-based nanotherapeutics such as nanoemulsions are gaining popularity as nutraceutical delivery systems due to their efficacy in improving the solubility, stability and bioavailability of the loaded food components. Curcumin, a potential component of Indian diet is not only a potential anticancer but also possess remarkable antioxidant properties. The paper exploits the formulation of curcumin loaded O/W nanoemulsion of Tween 80/Lecithin/ethyl oleate (EO)/water by controlling the oil/surfactant ratio. The mean droplet diameter (about 24 +/- 6 nm) and stability of nanoemulsion has been characterized by particle size estimation and IN-visible absorption spectroscopic studies. Attempt has been made to understand in vitro, loading and release of the formulated nanoemulsion. The hydrolysis of curcumin (degradation) at pH 7.4 has been controlled by encapsulating it in nanoemulsion. Interactions of curcumin with bovine serum albumin in aqueous medium have also been studied. Structural analysis shows that curcumin binds BSA via polypeptide polar groups with overall binding constants of K = 2.863 +/- 0.042 x 10(4) M-1. The number of binding site (n) is 0.98 for curcumin at 25 degrees C. (C) 2015 Elsevier B.V. All rights reserved.