Claude, Albert (1899-1983), a Belgian American cell biologist, helped establish modern cell biology and developed methods to analyze cell structures. For his work, Claude shared the 1974 Nobel Prize in physiology or medicine with Christian Rene de Duve of Belgium and George Emil Palade, a Romanian-born American.

Claude attended school for a few years, but when he was 12, he went to work in a steel mill. During World War I (1914-1918), he served in the British Intelligence Service and earned medals for bravery. In 1922, when the Belgian government announced that war veterans did not need a high school diploma to attend a university, Claude enrolled in medical school at the University of Liège. He received an M.D. degree in 1928 and completed his postdoctoral study in 1929 at the Kaiser Wilhelm Institute in Dahlem-Berlin. He sailed to the United States to work at Rockefeller Institute (now Rockefeller University) in New York City.

Claude devised the technique of cell fractionation to separate cell constituents by ultracentrifugation, a process in which cells are broken into particles of uniform size and then centrifuged to separate them for study. He introduced the use of an electron microscope to observe cell structures and discovered the endoplasmic reticulum, a lace-like network within the cell. He and his colleagues were the first to identify the mitochondria as the powerhouse of the cell.

Claude and Joy Gilder married in 1935, and Claude became an American citizen in 1941. The couple had one daughter, and the marriage ended in divorce.

In 1948, Claude returned to Brussels. He regained his Belgian citizenship a year later. He served as director of the Jules Bordet Institute in Brussels until his retirement in 1971 and also became director of the Laboratory of Cellular Biology and Oncology at the Catholic University in Louvain.