Theodor Svedberg was a Swedish chemist born in Flerang, Sweden on August 30th, 1884. He won the Nobel Prize for chemistry for his studies in the field of colloids and also for the invention of the ultracentrifuge in 1926.
Early Life and Work
Svedberg studied at the University of Uppsala where he obtained his doctorate in 1907. His early work involved the study of colloids, which are particles too small to be viewed by a light microscope. Instead they have to be dispersed throughout a substance like water. Water has to be used to keep these particles from settling due to gravity, since water molecules keep jostling them around. Svedberg used a centrifugal force to imitate the effects of gravity oCn colloids. It is because of his studies that we are able to tell the difference between pure proteins and other proteins.
Invention of Ultracentrifuge
Svedberg invented the ultracentrifuge which he used to investigate molecular weights of very large molecules. Particles have a tendency to sink to the bottom because of gravity. One way to counter this is to use the Brownian motion which opposes this by the collision of molecules. This in turn can be measured by the rate of sedimentation which is dependant on the size and weight of the particles.
Svedberg applied this technique to measure the sediment in protein solution by using forces which were much stronger than the gravitational force of the Earth namely the ultracentrifuge forces. Using this he could measure molecular weights of proteins which were a lot higher than he thought.
Svedberg continued his whole tenure at the University of Uppsala where he became professor of physical chemistry in 1912 and finally the director of the Institute of Nuclear Chemistry in 1949.
Svedberg conducted a lot of studies in the field of Nuclear Chemistry. He contributed to the improvement of the cyclotron. Svedberg helped his student Arne Tisselius to develop the use of electrophoresis to analyze and separate proteins. The unit of time Svedberg (symbol S) amounting to 10−13 s or 100 fs, is named after him.
Throughout his lifetime he wrote many popular books including 'Die Methoden zur Herstellung kolloider Losungen anorganischer Stoffe (1909), Die Existenz der Molekule (1912), Colloid Chemistry (1914), The Ultracentrifuge (with K.O. Pedersen 1940; also in German), Materien (1912), Arbetets dekadens (1915) and Forskning och Industri (1918). He also won many honours like the John Ericsson Medal (1942), the Berzelius Medal (1944), and the Medal of the Franklin Institute (1949). Last but not the least he won the Nobel Prize for chemistry in 1926.