Rachel Fuller Brown was born on November 23, 1898 in Springfield Massachusetts. While she didn't become interested in chemistry until she was a sophomore at Mount Holyoke College, she graduated with degrees in both history and chemistry. Dr. Emma Perry Carr encouraged her to obtain an advanced degree in chemistry, which she did, earning an M.S. in organic chemistry from the University of Chicago in 1920. Following that she taught at a girls' preparatory school/junior college for three years.

In 1924, Brown went back to the University of Chicago for two years. Here she investigated a pneumococcal-specific polysaccharide, which could be used to identify one of the types of bacteria causing pneumonia. She completed her coursework and research, but ran out of funding at that point. She continued her research by working as a laboratory technician at the Division of Laboratories and Research, New York State Department of Health, in Albany, New York. With her supervisor there, Dr. Augustus Wadsworth, she developed a test to distinguish the unique polysaccharide coating on each type of pneumococcus. Brown presented this work at a conference in Chicago in 1933 and also completed her oral examination then, qualifying to become Dr. Rachel Brown.

Dr. Wadsworth hired Elizabeth Hazen, a mycologist, to work with Brown on developing antifungal materials. Hazen collected samples, grew cultures, and sent them to Brown to extract the active components who sent them back to Hazen for testing on fungus. In general the active ingredients were too toxic for human use. Finally, Hazen sent Brown a sample produced by a previously unknown organism that appeared to have a low toxicity. Brown isolated the active ingredient, which seemed to be quite effective against the fungi they used for testing. They named it "nystatin" after New York State. Their discovery was made public late in 1950. They worked with the Research Corporation to obtain a patent and to negotiate with E. R. Squibb to develop and sell the products. Neither Brown nor Hazen wanted any of the royalties for herself, so the royalties were split between the Research Corporation and the Brown-Hazen Fund. This fund supports research in the biological and related sciences at nonprofit scientific and education institutions.

Nystatin has been used widely to combat various fungal diseases that affect humans, such as ringworm, as well as those that affect plants, such as Dutch Elm Disease, fungi that cause spoilage of bananas, and those that attack paintings.

Brown and Hazen continued to collaborate on antifungal research until 1975 when Hazen died. They received the Chemical Pioneer Award from the American Institute of Chemists in 1975.

Rachel Fuller Brown remained active in chemical research until her death on January 14, 1980 in Albany, New York.

National Inventors' Hall of Fame: Nystatin and the Method of Producing It

Baldwin, Richard S. The Fungus Fighters: Two Women Scientists and Their Discovery; Cornell University Press: Ithaca, NY, 1981.

Haber, Louis. Women Pioneers of Science; Harcourt Brace Jovanovich: New York, 1979; pp 63-72.

Rayner-Canham, Marelene and Rayner-Canham, Geoffrey. Women in Chemistry: Their Changing Roles from Alchemical Times to the Mid-Twentieth Century; American Chemical Society: Washington, DC, 1998; pp 146-150.

Smith, Roger. Biographies of Scientists, An Annotated Bibliography; Salem Press: Pasadena, CA, 1998; p 15.