Related Experiment Video
Updated: May 29, 2026

Polyethyleneimine-coated Iron Oxide Nanoparticles as a Vehicle for the Delivery of Small Interfering RNA to Macrophages In Vitro and In Vivo
Published on: February 5, 2019
The internalization pathway, metabolic fate and biological effect of superparamagnetic iron oxide nanoparticles in
Jingli Gu1, Haifei Xu, Yehua Han
1Department of Physiology and Pathophysiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing 100005, China.
Abstract:
The potential applications of superparamagnetic iron oxide nanoparticles (SPIONs) in several nanomedical fields have attracted intense interest based on the cell-nano interaction. However, the mechanisms underlying cell uptake, the intracellular trail, final fate and the biological effects of SPIONs have not yet been clearly elucidated. Here, we showed that multiple endocytic pathways were involved in the internalization process of SPIONs in the RAW264.7 macrophage. The internalized SPIONs were biocompatible and used three different metabolic pathways: The SPIONs were distributed to daughter cells during mitosis; they were degraded in the lysosome and free iron was released into the intracellular iron metabolic pool; and, the intact SPIONs were potentially exocytosed out of the cells. The internalized SPIONs did not induce cell damage but affected iron metabolism, inducing the upregulation of ferritin light chain at both the mRNA and protein levels and ferroportin 1 at the mRNA level. These results may contribute to the development of nanobiology and to the safe use of SPIONs in medicine when administered as a contrast medium or a drug delivery tool.

