Sarah Ratner is a biochemist whose research has focused on amino acids, the subunits of protein molecules. Her use of nitrogen isotopes to study metabolism --the chemical processes by which energy is provided for the body--resulted in the discovery of argininosuccinic acid, a substance formed by a sequence of reactions that take place in the liver. Ratner's awards for her work include the Carl Neuberg Medal from the American Society of European Chemists in 1959.

Ratner was born in New York City on June 9, 1903, the daughter of Aaron and Hannah (Selzer) Ratner. She received her bachelor of arts degree from Cornell University before proceeding to Columbia University for graduate studies, where she received an M.A. in 1927. Ratner worked as an assistant in biochemistry in the College of Physicians and Surgeons of Columbia University until she received her Ph.D. in biochemistry from the university in 1937. Following her graduation...