Rosalyn Sussman Yalow was co-developer of radioimmunoassay (RIA), a technique that uses radioactive isotopes to measure small amounts of biological substances. In widespread use, the RIA helps scientists and medical professionals measure the concentrations of hormones, vitamins, viruses, enzymes, and drugs, among other substances. Yalow's work concerning RIA earned her a share of the Nobel Prize in physiology or medicine in the late 1970s. At that time, she was only the second woman to receive the Nobel Prize in medicine. During her career, Yalow also received acclaim for being the first woman to attain a number of other scientific achievements.

Yalow was born on July 19, 1921, in The Bronx, New York, to Simon Sussman and Clara Zipper Sussman. Her father, owner of a small business, had been born on the Lower East Side of New York City to Russian immigrant parents. At the age of four, Yalow's mother had...