Nanoparticles based on oleate alginate ester as curcumin delivery system

Hydrophobic alginate derivative was prepared by the modification of alginate with methyl oleate. The synthesized oleate alginate ester (OAE) conjugate was characterized by FTIR and 1HNMR analysis. Results of critical aggregation concentration (CAC) revealed that OAE conjugate had low CAC and was prone to form self-assembled nanoparticles in aqueous medium. Curcumin loaded OAE nanoparticles (Cur-OAE Nps) were developed by a simple sonication method and the physicochemical parameters of the nanoparticles such as zeta potential, size distribution and drug encapsulation were characterized. The results showed that zeta potential of the prepared nanoparticles was -55.4±0.91 mV and the average size was about 200 nm. A significant enhancement in aqueous solubility and stability of curcumin were observed after encapsulation into OAE nanoparticles. With the increase of curcumin concentration, loading efficiency increased but encapsulation efficiency decreased. The in vitro release profile exhibited significant sustained release pattern with initial burst release followed by a slower release over a period of one week. Cytotoxicity assay against MCF-7cells showed that Cur-OAE Nps had slow and continuous cytotoxic effect. Furthermore, in vitro cell uptake study revealed that cell uptake of curcumin from OAE nanoparticles was sustained and both were time and concentration dependent. Therefore, the developed Cur-OAE Nps might be promising candidates for curcumin delivery to cancer cells.