Nanotech News

September 19, 2005

Multifunctional Magnetic Nanocrystals Provide Dual Imaging of Cancer Cells

Magnetic nanocrystals have shown promise as tools for detecting cancer using magnetic resonance imaging (MRI). Now, new research from a team of investigators led by Jeon-Soo Shin, M.D., Ph.D., and Jinwoo Cheon, Ph.D., both of Yonsei University in Seoul, South Korea, demonstrates that antibody-labeled magnetic nanocrystals used with MRI can rapidly detect breast cancer cells in a living animal. This work was published in the Journal of the American Chemical Society.

Building on their initial efforts at preparing antibody-labeled magnetic nanocrystals (click here to see previous story), the investigators now report on their work with an improved water-soluble antibody-nanocrystal conjugate that binds tightly to the HER2/neu receptor that is overexpressed on certain types of breast cancer and which is targeted by the anticancer therapy Herceptin^®. The researchers describe how they make their magnetic nanocrystals and link the nanoparticles to the Herceptin antibody. They then demonstrate that this formulation, when injected into mice bearing human breast tumors, travels quickly to the site of the tumors and renders them visible in an MRI scan. Tumors are visible within an hour after nanocrystal injection.

The investigators then showed that adding a fluorescent label to the nanocrystal-antibody formulations enabled them to image breast cancer cells growing in culture using a fluorescent microscope. In practice, this labeling suggests that these nanocrystals could be used to both detect breast cancer using MRI and then provide an optical signal during surgery to aid in the complete removal of all malignant tissue.

This work is detailed in a paper titled, “In Vivo Magnetic Resonance Detection of Cancer by Using Multifunctional Magnetic Nanocrystals.” An abstract is available through PubMed. View abstract.