PEG/RGD-modified magnetic polymeric liposomes for controlled drug release and tumor cell targeting

Polymeric liposomes (PEG/RGD-MPLs), composed of amphiphilic polymer octadecyl-quaternized modified poly (γ-glutamic acid) (OQPGA), PEGylated OQPGA, RGD peptide grafted OQPGA and magnetic nanoparticles, was prepared successfully. These PEG/RGD-MPLs could be used as a multifunctional platform for targeted drug delivery. The results showed that PEG/RGD-MPLs were multilamellar spheres with nano-size (50-70 nm) and positive surface charge (28-42 mV). Compared with magnetic conventional liposomes (MCLs), PEG/RGD-MPLs exhibited sufficient size and zeta potential stability, low initial burst release and less magnetic nanoparticles leakage. The cell uptake results suggested that the PEG/RGD-MPLs (with RGD and magnetic particles) exhibited more drug cellular uptake than non RGD and non magnetism carriers in MCF-7 cells. MTT assay revealed that PEG/RGD-MPLs showed lower in vitro cytotoxicity to GES-1 cells at ≤100 μg/mL. These data indicated that the multifunctional PEG/RGD-MPLs may be an alternative formulation for drug delivery system.