Nanoparticles reveal then kill cancers…maybe

Go back to the beginning of MRI, in the early and mid-1980s, and you’ll find an almost rabid adoption of the modality, despite scant evidence of its clinical value. MRI has since done much to gain the trust of the medical community, opening a diagnostic cornucopia in the process. But the future has to bring more if MR is going to extend this legacy. Researchers at Wake Forest University Baptist Medical Center are working on it.

In research announced July 21 and presented at the American Association of Physicists in Medicine meeting in Philadelphia, they have created iron-containing multiwalled carbon nanotubes that, thanks to their ferrous character, show up beautifully on MRI.

Multiwalled carbon nanotubes are incredibly small concentric cylinders. They measure about a nanometer in diameter, about 1/10,000th the diameter of a human hair. But this alone is not enough to make them noteworthy. Nor is it sufficient to build them into MR imaging agents.

Iron-based imaging agents have been kicking around MRI labs for decades. What distinguishes them is the fact they absorb energy, laser energy to be exact, and turn it into heat.

Exposed to laser light while inside a tumor, these nanotubes become red-hot pokers that sear cancer at its cellular roots. Their iron content makes them visible with MRI, confirming they are in place to wreak oncologic mayhem.

Reflective of the research itself, progress with these nanoparticles is taking shape in tiny steps, actually mouse steps. As part of his ongoing Ph.D. thesis work at Wake Forest Baptist, Xuanfeng Ding demonstrated that the tiny particles were indeed visible under MRI and did heat up under laser light, so much that they could destroy tumor cells in which they have settled. Whether they ever will is hard to say.

A decade may pass from the inception of a good idea to the emergence of a pharmaceutical product. What’s remarkable—more remarkable than the potential of this one experimental concoction—is that this research is at once novel and routine: novel in the tailoring done to the particles to make them visible to MRI; routine in the tools applied during this process.

Nanotechnology is rapidly reshaping the future, it seems, for just about everything from imaging agents to electric car batteries. It is modern alchemy whose promise has not yet been achieved but, unlike medieval efforts to turn common metals into gold, likely will be.

How ironic that the very tiny will reshape the world on such a macro level.