Effect of the Folate Ligand Density on the Targeting Property of Folated‐Conjugated Polymeric Nanoparticles

Targeted drug delivery systems have attracted increasing attention due to their ability for delivering anticancer drugs selectively to tumor cells. Folic acid (FA)‐conjugated targeted block copolymers, FA‐Pluronic‐polycaprolactone (FA‐Pluronic‐PCL) are synthesized in this study. The anticancer drug paclitaxel (PTX) is loaded in FA‐Pluronic‐PCL nanoparticles by nanoprecipitation method. The in vitro release of PTX from FA‐Pluronic‐PCL nanoparticles shows slow and sustained release behaviors. The effect of FA ligand density of FA‐Pluronic‐PCL nanoparticles on their targeting properties is examined by both cytotoxicity and fluorescence methods. It is shown that FA‐Pluronic‐PCL nanoparticles indicated better targeting ability than non‐targeted PCL‐Pluronic‐PCL nanoparticles. Furthermore, FA‐F127‐PCL nanoparticle with 10% FA molar content has more effective antitumor activity and higher cellular uptake than those with 50% and 91% FA molar content. These results prove that FA‐F127‐PCL nanoparticle with 10% FA molar content can be a better candidate as the drug carrier in targeted drug delivery systems.