Influence of Physicochemical Properties and PEG Modification of Magnetic Liposomes on Their Interaction with Intestinal Epithelial Caco-2 Cells.

The present study aimed to investigate the effect of particle size (100, 500 nm), surface charge (cationic, neutral and anionic) and polyethylene glycol (PEG) modification of magnetic liposomes on their interaction with the human intestinal epithelial cell line, Caco-2. The cellular associated amount of all the magnetic liposomes was significantly increased by the presence of a magnetic field. The highest association and internalization into Caco-2 cells was observed with magnetic cationic liposomes. Moreover, small magnetic liposomes were more efficiently associated and taken up into the cells, than large ones. In contrast, PEG modification significantly attenuated the enhancing effect of the magnetic field on the cellular association of magnetic liposomes. We also found that magnetic cationic liposomes had the highest retention properties to Caco-2 cells. Moreover, the retention of large magnetic liposomes to the cells was much longer than that of small ones. In addition, magnetic cationic and neutral liposomes had relatively high stability in Caco-2 cells, whereas magnetic anionic liposomes rapidly degraded. These results indicate that the physicochemical properties and PEG modification of magnetic liposomes greatly influences their intestinal epithelial transport.