November 27, 2006
Targeted Nanoparticles for Liver Imaging
Coated iron oxide nanoparticles have proven useful as magnetic resonance imaging (MRI) contrast agents for detecting metastatic lesions in lymph nodes. Now, investigators at the Kyungpook National University in Korea have shown that these nanoparticles can be targeted specifically to liver cells, and as a result, could eventually provide clinicians with a highly sensitive method for spotting metastatic lesions in the liver.
Reporting its work in the journal Biomaterials, a research team headed by Inn-Kyu Kang, Ph.D., developed this liver-targeting contrast agent by coating magnetic nanoparticles with lactobionic acid, a type of sugar that binds to a receptor on the surface of liver cells known as hepatocytes. When the investigators added these nanoparticles to cultured liver cells, the nanoparticles accumulated inside the cells. In contrast, liver cells took up very few nanoparticles coated with a related sugar known as maltotrionic acid, indicating that lactobionic acid was indeed acting as a hepatocyte targeting agent.
Next, the researchers injected the nanoparticles into rabbits. MRI scans of the rabbits showed clear evidence that the nanoparticles were accumulating in the liver. The resulting MR images showed no evidence of nanoparticle accumulation within the lung or bile duct.
This work is detailed in a paper titled, “Surface modification of magnetite nanoparticles using lactobionic acid and their interaction with hepatocytes.” This paper was published online in advance of print publication. An abstract is available through PubMed.