New dendrimer-based nanoparticles enhance solubility of curcumin.

Curcumin, the main curcuminoid of the popular Indian spice turmeric, is a potent chemopreventive agent and useful in many different diseases. A major limitation of applicability of curcumin as a health promoting and medicinal agent is its extremely low bioavailability due to efficient first pass metabolism, poor gastrointestinal absorption, rapid elimination and poor aqueous solubility. In the present study nanotechnology was selected as a choice approach to enhance bioavailability of curcuminis. A new PAMAM dendrimer (G0.5) was synthesized and characterized and tested for the cytotoxicity in MCF-7 cells. No cytotoxicity of G0.5 was found in the range between 10-3 and 3x10-8 M. Consequently, G0.5 was used to prepare spherical nanoparticles (NPs) of ca. 150 nm, which were loaded with curcumin (molar ratio G0.5/curcumin 1:1 and 1:0.5). Remarkably the occurrence of a single population of NPs having an excellent polydispersity index (<0.20) was found in both formulations. Formulation having a molar ratio G0.5/curcumin 1:1 was selected to test in vitro drug release because superior in terms of EE% (62%) and LC% (32%). Solubility of curcumin was increased ca. 415 and 150 times with respect with the unformulated drug, respectively for formulation 1 and formulation 2. The release of curcumin from the NPs showed an interesting prolonged and sustained release profile.