Rosayln S Yalow was born in New York in 1921. She was awarded the Nobel Prize in medicine for the development of the technique of radioimmunoassay in 1977. Dr. Yalow was not an immunologist but an endocrinologist who was studying diabetes millitus. She required a method of measuring the very low levels of antibodies against insulin with a radioisotope. This technique was eventually refined so that exquisitely small levels of molecules such as hormones could be readily measures. The technique of radioimmunoassay is now used in many fields other than endocrinology

(From Tizard an introduction to Immunology 4th edi p 251