Svedberg, Theodor (1884-1971) was a Swedish chemist who won the 1926 Nobel Prize in chemistry for his work on disperse systems.
Born in Flerang, Sweden, Svedberg studied chemistry at the University of Uppsala, where he received a B.S. degree in 1905. He prepared his doctoral thesis on colloids, a material composed of tiny particles of one substance that are dispersed, not dissolved, throughout another substance. He earned a Ph.D. degree in 1907. He joined the faculty of Uppsala, where in 1912 he became professor of physical chemistry. He was made professor emeritus in 1949 and was director of the Gustaf Werner Institute of Nuclear Chemistry until he resigned in 1967.
Svedberg researched colloids using an ultramicroscope, which uses refracted light to visualize specimens that are too small to see with direct light. He studied the sedimentation of particles in the colloidal substance. He noted that the smallest colloidal particles in some solutions did not settle out under the force of gravity and therefore could not be examined. He solved the problem by developing the ultracentrifuge. Although centrifuges were already being used to separate milk from cream and red blood cells from plasma, none were strong enough to separate out the smaller and lighter colloidal particles. The ultracentrifuge generated a gravitational force hundreds of thousands of times greater than the earth's. He separated the smallest particles from the colloidal substance and established that molecules of certain pure proteins are all of one size and that contaminants could be detected and removed by the process.
The ultracentrifuge has become an invaluable tool in the field of biochemistry, allowing for research into proteins such as hemoglobin, insulin, and catalase, and also for studying viruses and for genetic engineering.
During World War II (1939-1945), he also developed a method for producing synthetic rubber.