Florence B. Seibert was an American biochemist best known for her contributions to the tuberculin test and to safety measures for intravenous drug therapy. She is a member of the U.S. National Women’s Hall of Fame.
Seibert was born in Easton, Pennsylvania. As the age of three she contracted polio which left her with a lifelong limp. When Seibert was a teacher she read biographies of famous scientists which lead to her interest in the subject. She graduated as high school valedictorian before continuing her education at Goucher College in Maryland. She studied chemistry and zoology on a scholarship. After graduating from College in 1918, Seibert worked briefly as a chemist at Hammersley Paper Mill under the direction one of her chemistry teachers, Jessie E. Minor. Seibert and Minor were responsible for filling positions vacated by men fighting in World War I. Together they co-authored scientific papers on the chemistry of cellulose and wood pulps.
Seibert moved on from the Paper Mill after winning a scholarship to attend Yale University. She earned a doctorate in biochemistry from Yale in 1923. While at Yale, Seibert discovered that intravenous injections made with contaminated distilled water could cause fevers in patients. She was able to devise an improved method for making distilled water which eliminated all bacteria.
In 1924 Seibert worked as a postdoctoral fellow at the University of Chicago, her position was paid for by the Porter Fellowship of the American Philosophical Society. She then moved on to teach pathology at the Sprague Memorial Institute in Chicago where she started as an instructor before being promoted to assistant professor of biochemistry. While at the Sprague Memorial Institute in Chicago Seibert began working with Esmond R. Long whom she had met at seminars at the University of Chicago. They were supported by a grant from the National Tuberculosis Association and together spent thirty-one years collaborating on tuberculosis research.
In 1891 Robert Koch had discovered that animals previously infected with tuberculosis reacted when tuberculosis bacteria fragments or dead bacteria were injected under the skin. The reaction, caused by the culture extract tuberculin was called the tuberculin reaction and was caused by an immune response called delayed hypersensitivity. Koch was unable to create consistent batches of tuberculin which proved problematic for testing. Seibert was able to develop a method of isolating and purifying the active substance in tuberculin under the supervision of Esmond R. Long. She refined her research while a Guggenheim fellow at the University of Uppsala, Sweden where she learned new techniques for the separation and identification of proteins in solution. On her return from Sweden she was able to create large, consistent batches of purified protein derivative (PPD) to serve as the basis for a standard dosage of the first reliable tuberculin test. The test was adopted as the standard by the United States in 1941 and by the World Health Organization in 1952 and is still in use today. She received the 1938 Trudeau Medal from the National Tuberculosis Association for her work.
In 1932 Long transferred to the University of Pennsylvania’s Henry Phipps Institute and Seibert followed. Seibert was able to rise from assistant professor to associate professor to full professor of Biochemistry before retiring in 1958. Seibert served as a consultant to the United States Public Health Service and then as director of the Cancer Research Laboratory at the Mound Park Hospital. She also continued to conduct research in a small laboratory in the same hospital. She devoted herself to studying the bacteria associated with certain types of cancers. She was inducted into the National Women’s Hall of Fame in 1990, a year before her death.