Doisy, Edward A. (Adelbert)(1893–1986) biochemist; born in Hume, Ill. He was an assistant in biochemistry at Harvard Medical School (1915–17), then moved to the Washington University (St. Louis, Mo.) School of Medicine (1919–23). He joined the St. Louis University School of Medicine (1923–65), while concurrently serving as administrator and director of St. Mary's Hospital, St. Louis (1924–86). In collaboration with American embryologist Edgar Allen, he developed the Allen-Doisy vaginal smear for assaying estrogen potency; the two scientists also purified several female sex hormones (1929–35). In 1939 Doisy isolated two forms of the coagulant vitamin K. For this contribution to the treatment of hemorrhagic disorders, he shared the 1943 Nobel Prize for physiology. He also made major advances in antibiotic research, the biochemistry of bodily buffer systems, and the purification of insulin and the placental hormone chorionic gonadotropin.