The team found to its surprise in its experiments that a single mother-ship can carry multiple iron oxide nanoparticles, which increases their brightness in the MRI image.
"The ability of these nanostructures to carry more than one superparamagnetic nanoparticle makes them easier to see by MRI, which should translate to earlier detection of smaller tumors," said Sailor. "The fact that the ships can carry very dissimilar payloadsa magnetic nanoparticle, a fluorescent quantum dot, and a small molecule drugwas a real surprise."
The researchers noted that the construction of so-called "hybrid nanosystems" that contain multiple different types of nanoparticles is being explored by several other research groups. While hybrids have been used for various laboratory applications outside of living systems, said Sailor, there are limited studies done in vivo, or within live organisms, particularly for cancer imaging and therapy.
"That's because of the poor stability and short circulation times within the blood generally observed for these more complicated nanostructures," he added. As a result, the latest study is unique in one important way.
"This study provides the first example of a single nanomaterial used for simultaneous drug delivery and multimode imaging of diseased tissue in a live animal," said Ji-Ho Park, a graduate student in Sailor's laboratory who was part of the team. Geoffrey von Maltzahn, a graduate student working in Bhatia's laboratory, was also involved in the project, which was financed by a grant from the National Cancer Institute of the National Institutes of Health.
The nano mother ships look individually like a chocolate-covered nut cluster, in which a
|Contact: Kim McDonald|
University of California - San Diego