Enhanced cellular uptake of iron oxide nanoparticles modified with 1,2-dimyristoyl-sn-glycero-3-phosphocholine

Abstract

It is important for nanoparticles to enter cells to implement their biological applications. We synthesized and characterized superparamagnetic iron oxide nanoparticles (SPIONs) modified with poly(ethylene glycol) (PEG) and polyethyleneimine (PEI) (PEG/PEI-SPIONs), and further with 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) (DMPC-SPIONs) to improve their intracellular uptake. The nanoparticles internalized into PC-12 cells were observed by transmission electron microscopy (TEM) and quantified by inductively coupled plasma emission spectroscopy (ICP-OES). There was a much greater uptake of DMPC-SPIONs than PEG/PEI-SPIONs into PC-12 cells and remarkable amounts of accumulated nanoparticles were found in the lysosome, endoplasmic reticulum, mitochondria, vesicles, and around the nucleus, and some nanoparticles remained on the cell membrane. This can be attributed to the similarity between the chemical structures of DMPC and membrane phospholipids which result in the fusion of DMPC and cell membranes. Our results encourage further research on DMPC-SPIONs as drug carriers, transfection agents, MRI contrast agents for cells and hyperthermia agents.