Seibert, Florence B. (1897–1991)

American biochemist who developed the skin test for tuberculosis. Born Florence Barbara Seibert on October 6, 1897, in Easton, Pennsylvania; died on August 23, 1991; daughter of George Peter Seibert and Barbara (Memmert) Seibert; Goucher College, A.B. and LL.D.; University of Chicago, Sc.D.; Yale University, Ph.D.

For her work in developing a reliable skin test for tuberculosis, once the leading cause of death in America, Florence Seibert earned distinction as one of the country's greatest biochemists. Writing shortly after this accomplishment, Edna Yost noted, "The tuberculin Florence Seibert 'discovered' can be depended upon to give identical tests because she found the way to isolate pure tuberculin from its impurities. It took her ten years to do it. But that is not bad when you stop to consider that many others had been attempting over a sixty-year period to do it." Among the honors Seibert received for her work were a Guggenheim Fellowship (1937), the Trudeau Gold Medal from the National Tuberculosis Association (1938), the Garvan Gold Medal from the American Chemical Society (1942), several honorary degrees, and induction into the Women's Hall of Fame (1990).

She was born in 1897 in Easton, Pennsylvania, and had two siblings, an older brother Russell and a sister Mabel Seibert . Both Russell and three-year-old Florence were victims of the polio epidemic which swept through Easton. Their parents, George and Barbara Seibert , helped them to learn to walk with braces, which were later discarded, and relocated the family so that Florence and Russell would be nearer to school. "Because I was disabled," noted Seibert, "I stuck to things harder"; she also replaced activities which were out of her reach, like going to dances, with study. On the night that she graduated from Easton High School, she received a scholarship to Goucher College in Baltimore, Maryland. But her father was concerned about her enduring the physical challenges of a college campus, so that September he accompanied her there; he left within a week. George had quickly realized that she was at home in her new environment. "I learned … that I was not an invalid but could stand on my own two feet with a chance to make a contribution to the world."

Telling her teachers, "I'm going to Johns Hopkins and become a doctor," Seibert ignored those friends and faculty members who advised her against what they considered a difficult pursuit for a woman, particularly a woman with a disability. She took pre-med courses, despite knowing that her family did not have the means to put her on the path to Johns Hopkins, but changed direction upon an invitation from Jessie Minor (who had been her chemistry teacher) to work at the Hammersley Paper Mill Company's chemistry lab. Following Seibert's graduation in 1918, the two women worked there on behalf of the war effort, affording Seibert an opportunity to raise funds for graduate study. The two also collaborated on three papers which were printed in technical journals.

With the help of fellowships, Seibert received her Ph.D. from Yale in 1923. Her graduate work focused on creating a method for removing contaminants from distilled water. At the time, noted Kathleen McLaughlin , "triple-distilled water was used as a solvent for intravenous injections, but fever frequently followed such treatment. Few physicians believed that the triple-distilled water could be to blame until Dr. Seibert analyzed the water and found bacteria or bacterial products enough to induce the fever." Finding that the bacterial products were transmitted in the steam, Seibert adapted the apparatus used for distillation by "inserting a new loop, or baffle," an advancement which made possible contaminant-free water with no more than a single distillation.

A Porter Fellowship brought Seibert to the University of Chicago, where she took a position as instructor in pathology and assistant in the Sprague Memorial Institute. An award which she received at the University of Chicago, where she continued the work begun at Yale, provided the funds for her to purchase a car designed to enable her to drive with her stronger foot.

In her department was Esmond R. Long, a grant recipient from the National Tuberculosis Association, to whom Seibert served as assistant. Invited to join Long in his research, in 1924 Seibert began the work with tuberculosis for which she would be famous. Long's goal at the time, noted Yost, was to "ascertain first the chemical nature of the specific substance in raw tuberculin which gave a positive skin reaction in the tuberculous individual, and then to produce a tuberculin of such a state of purity that when any doctor anywhere injected it into a human being, he could know that whatever happened was an exact scientific result with a definite significance." Prior to Seibert's work, no tuberculin had been developed which was free of impurities. Consequently, depending on how high the test dose was in impurities, a tubercular individual might test negative for tuberculosis, making skin tests unreliable.

It was Seibert who managed to determine that pure tuberculin was a protein. Purifying this protein, however, was daunting work which took her years. The pure tuberculin which she isolated was a Purified Protein Derivative (PPD) of the tubercle bacillus. Seibert continued her work in Chicago, where she eventually became associate professor in biochemistry (1928), before following Long to the University of Pennsylvania's Henry Phipps Institute. In Pennsylvania, she was promoted from assistant to associate professor in 1937. That year, she received a Guggenheim Fellowship which made possible a year's study in Uppsala, Sweden, where she worked with the Nobel Prize-winning Swedish professor The (Theodor) Svedberg and his pupil Arne Tiselius. The latter had developed equipment which used an electrical field to separate molecules in a process known as electrophoresis. A grant from the Carnegie Foundation made it possible for the Henry Phipps Institute to procure Tiselius' new apparatus, and Seibert continued her work with the PPD upon her return. Having become an international

authority on the bacillus responsible for tuberculosis, she prepared the National Standard for Tuberculins in 1939, and by 1941 the skin test was ready for use.

But hesitancies on the part of the medical establishment were compounded by delays due to the outbreak of the Second World War, and it would be another several years before this test received approval for widespread use. Seibert met resistance when she testified before the World Health Organization in 1952, later remarking: "They thought that if they didn't have a big man there arguing for the test, they could push [out] this method." At 4′9″, and less than 100 pounds, Seibert was hardly a big man. Disabled from her childhood experience with polio, she once remarked that she remembered her physical limitations only when approaching a full-length mirror: "That's the only time I ever remember it. And even in my forties I'm still brought up with a jolt every time I get in front of a mirror and see myself coming."

Among the 20th century's most eminent biochemists, Seibert retired eight years before the skin test developed from her work became the standard in 1966. In Florida, she and her sister Mabel, who had served as her laboratory assistant for years, worked voluntarily on cancer research. Seibert was inducted into the Women's Hall of Fame in 1990, a year before her death at age 93.

sources:

Bailey, Brooke. The Remarkable Lives of 100 Women Healers and Scientists. Holbrook, MA: Bob Adams, 1994.

Block, Maxine, ed. Current Biography 1942. NY: H.W. Wilson, 1942.

Weatherford, Doris. American Women's History. NY: Prentice Hall, 1994.

Yost, Edna. American Women of Science. Philadelphia, PA: Frederick A. Stokes, 1943.