Year of Invention: 1955
What Is It? A blood test that measures trace amounts of blood components.
Who Invented It? Rosalyn Yalow (in New York)
The 1977 Nobel Prize committee wrote that Rosalyn Yalow’s radioimmunoassay (RIA) “brought a revolution in biological and medical research.” They said that it was “more important than the discovery of X-rays.”
RIA is used to measure hormones, vitamins, enzymes, toxins, and other trace elements too minute to be otherwise detected. For the first time in history, doctors could accurately diagnose conditions associated with minute changes in hormones—some cancers, hypertension, diabetes, thyroid disease, and sterility. Criminologists use RIA to detect the minute presence of lethal drugs in corpses. The versatility and dependability of this procedure have made it one of the most effective diagnostic tools ever invented.
Doctors struggled to make accurate diagnoses of many diseases through the mid-twentieth century, often having to base a diagnosis on indirect information and indirect clues. Far too often a firm diagnosis required specific chemical information that doctors had no way to obtain. Diagnosis was more art than precise science.
By age eight (in 1930), Rosalyn Sussman (her married name was Yalow) decided that she wanted to be a “big-deal scientist.” She liked knowing things; she liked logic.
When the United States entered World War II, the draft quickly depleted graduate programs of their male students. For a few short years, graduate programs opened their doors to women. Rosalyn received her Ph.D. in nuclear physics in 1945 and moved back to New York City. Radioisotopes (artificially produced radioactive substances) were just coming into use in medicine, and in 1947, Yalow began her work in nuclear medicine for the Veterans Affairs Medical Center in the Bronx.