Other patients may be better off undergoing other treatments.
“When most people think about carbon dating, they think about dating objects that are thousands of years old,” says Bench.
Scientists are beginning to study the possibility of giving patients very small doses of chemotherapy drugs laced with a radioactive tracer. But they are large enough that, when a researcher views the patient’s blood a few hours later using AMS, she can determine whether the drug has successfully bound to DNA, as it is supposed to, or if something in the patient’s biological makeup stopped this binding from taking place.
Chemotherapy, one of the most common cancer treatments, is not effective for everyone; as many as 40 percent of patients don’t respond to treatment.
Carbon dating relies on carbon-), which corresponds to a sample age of 50,000 years.
Another highly sensitive technique is optical spectroscopy, which detects small quantities of a substance by measuring the amount of light it absorbs.
But the system De Natale and his colleagues have developed is times more sensitive because it can isolate the two types of losses with the sample present.
For this calibration step, the system essentially turns off the absorption for a short time by using a laser with sufficient power to excite all of the target molecules, putting them into a state in which they can’t absorb light.These vastly different projects have one thing in common: They all use accelerators to measure levels of carbon-14 and other isotopes.