Galactosylated chitosan–polycaprolactone nanoparticles for hepatocyte-targeted delivery of curcumin

► Galactosylated chitosan–polycaprolactone is synthesized for delivery of curcumin. ► Initial load of curcumin in the resulting nanoparticles reaches around 6%. ► Curcumin release from nanoparticles is controlled by polycaprolactone component. ► Nanoparticles have hepatocyte-targeted specificity toward HepG2 cells. ► Bioavailability of curcumin can be greatly improved using these nanoparticles. Galactosylated chitosan–polycaprolactone (Gal-CH–PCL) copolymers with a galactosylation degree of around 10% and varied PCL percentages less than 40wt% were synthesized and used to produce nanoparticles for delivering curcumin. Some nanoparticles with encapsulation efficiency of 70% or higher and sizes changing from 100 to 250nm were able to deliver curcumin in a controlled manner. PCL content in Gal-CH–PCLs was found to be a key factor for governing the release behavior of nanoparticles. Hepatocyte-targeted characteristic of nanoparticles was confirmed using human hepatocellular carcinoma (HepG2) cells. In comparison to free curcumin, curcumin-loaded Gal-CH–PCL nanoparticles well retained its anticancer activity. At an equivalent curcumin-dose of around 20μg/mL that was found to be relatively safe to human normal liver cells, the results obtained from flow-cytometry revealed that some optimized Gal-CH–PCL nanoparticles showed more than 6-fold increasing abilities to induce the apoptosis and necrosis of HepG2 cells during 72h treatment compared to free curcumin.