A comparative study of polydopamine modified and conventional chemical synthesis method in doxorubicin liposomes form the aspect of tumor targeted therapy.

Polydopamine (PDA) has been a simple, novel and versatile method to prepare targeted nanoparticles, which can be used as a platform for conjugating targeted ligands to polymer carriers without reactive chemical groups. To better understand the difference between the novel PDA method and conventional chemical synthesis way, we developed two kinds of folate (FA)-targeted liposomes loaded doxorubicin (DOX) by the above methods. FA-PDA-DOX liposomes and DOX-FA liposomes represented PDA and conventional method, respectively. FA-PDA-DOX liposomes had a smaller particle size than DOX-FA liposomes, and both of them presented good stability, spherical morphology, strong inhibition effect to HeLa cells and high drug accumulation in the tumor site. There were no significant differences between the two targeted liposomes in the in vitro cytotoxicity study and in vivo bio-distribution assay. While only FA-PDA-DOX liposomes showed pH-sensitive properties, which was attributed to the PDA layers and can control the drug release better. Compared to DOX-FA liposomes, FA-PDA-DOX liposomes were much safer in an antitumor experiment in vivo, and the inhibition rate was still over 70%. This study demonstrated the PDA method could achieve therapeutic levels similar to traditional methods in a simpler and safer way, which can be useful and promising nanocarriers for drug delivery system in the future.