In order to increase the bioavailability of hydrophilic unstable drugs like anthocyanins， we employed a polymer-based nanoparticles approach due to its unique properties such as high stability， improved bioavailability and high water-soluble drug loading efficiency. Anthocyanins constitute a subfamily of flavonoids that possess anti-oxidative， anti-inflammatory and neuroprotective properties. However， anthocyanins are unstable because their phenolic hydroxyl groups are easily oxidized into quinones， causing a reduced biological activity. To overcome this drawback and improve the free radical scavenging capabilities of anthocyanins， in the current study we for the first time encapsulated the anthocyanins in biodegradable nanoparticle formulation based on poly (lactide-co-glycolide) (PLGA) and a stabilizer polyethylene glycol (PEG)-2000. The biological activity and neuroprotective effect of anthocyanin loaded nanoparticles (An-NPs) were investigated in SH-SY5Y cell lines.