In Translation

Dawn of a New Machine

A gargantuan machine can trace carcinogens and other tiny particles as they travel through living tissues.

But for a small handful of now-indispensable machines, medicine as we know it today would not exist: the microscope, which permitted discovery of the cell; the hypodermic syringe, which made blood transfusion possible; the x-ray, which allowed doctors to see inside the body without cutting it open.

Now another new machine — the accelerator mass spectrometer, or AMS — is again transforming medical science.
“It’s opened up a world for us equivalent to what the microscope did for biologists,” said Ken Turteltaub, a toxicologist and co-leader of the UC Davis Integrated Cancer Research Program’s biomedical molecular oncology program.

The AMS counts atoms that have been “tagged” with carbon-14 or another radioactive isotope. Insert a small sample of blood or tissue into the giant machine and it will tell you, within seconds, whether the tagged substance you’re looking for — a potential carcinogen, perhaps, or a chemotherapy drug — is present. The AMS can detect a single tagged atom out of a quadrillion (1,000,000,000,000,000).

This exquisite sensitivity enables scientists to measure exact levels of a tagged substance in the tissues of living human beings, even when only a faint trace of the substance is present.

Lawrence Livermore scientists Karen Dingley and Ken Turteltaub conducted some of the first human experiments using the accelerator mass spectrometer.