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			Robert J. Seiwald Born Mar 26 1925 Isothiocyanate Compounds and Means of Producing the Same Isothiocyanate Compounds (Antigen) Patent Number(s) 2,937,186 Inducted 1995 Antibodies are the body's protectors. When antigens, such as bacteria or viruses, enter the body, antibodies from a previous infection or vaccine combine with them and deactivate the invaders. During the 1950s, as medical researchers came to understand this relationship, it became a priority to identify antigens. Joseph Burckhalter and Robert Seiwald made an essential contribution to the identification of antigens through the synthesis of fluorescein isothiocyanate, better known as FITC. The first practical and first patented antibody labeling agent, the stable, yellow-green-fluorescent compound has become widely used for rapid, accurate, and economic diagnosis of infectious diseases. Invention Impact FITC has played an important role in identifying the cause of AIDS and can be used to distinguish between different strains of streptococci. It has proved infallible in tests for syphilis. FITC and red RITC (rhodamine isothiocyanate) are used together to quickly diagnose leukemia and lymphoma. FITC also paved the way for the development of other labeling procedures, such as radioimmunoassay and enzyme-linked immosorbent assay (ELISA). Inventor Bio Born in Columbia, South Carolina, Burckhalter earned a B.S. in chemistry from the University of South Carolina in 1934, an M.S. in organic chemistry from the University of Illinois, Urbana, in 1938, and a Ph.D. in medicinal chemistry from the University of Michigan in 1942. He then worked at Parke-Davis. From a pain-relieving drug now known as Tylenol, he derived, Camoquin, a cure for malaria. Burckhalter was a professor of medicinal chemistry at the University of Michigan from 1960 to 1983. Since 1983 he has been a research professor at Florida Institute of Technology. Born in Fort Morgan, Colorado, Seiwald served in World War II then he earned his B.S. in chemistry from the University of San Francisco and his Ph.D. in organic chemistry from St. Louis University in 1954. Later that year he joined Burckhalter at the University of Kansas, where they patented FITC and RITC. He was professor of organic chemistry at the University of San Francisco from 1957 until he retired in 1989.