Frederick G. Donnan

Biography

Frederick George Donnan was born on 6 September 1870 in Colombo, Ceylon (now Sri Lanka), and became a leading physical chemist in the early twentieth century. Of Irish descent, he studied at Queen's University Belfast before attending Leipzig University in Germany, where he learned under Wilhelm Ostwald, a key figure in physical chemistry. This education gave Donnan a strong foundation in thermodynamics and electrochemistry, which shaped his scientific career.

Donnan spent much of his career at University College London as a professor, gaining respect as both a researcher and teacher. His most famous work was the Gibbs–Donnan effect, or Donnan equilibrium, which describes how ions distribute across a semipermeable membrane when one side has a charged macromolecule that can't cross the membrane. This principle is essential for understanding osmotic pressure, membrane potential, and ionic transport in biological cells and is still an important concept in physical chemistry and physiology.

In addition to his work on membrane equilibria, Donnan made significant contributions to colloid chemistry and the theory of electrolyte solutions. During World War I, he applied his scientific expertise to national service, working on chemical production and industrial chemistry problems vital to Britain's war efforts. His work during this time earned him recognition, and in 1920 he was appointed Commander of the Order of the British Empire.

Throughout his life, Donnan received many honors, showing the wide respect he held in the scientific community. He was elected a Fellow of the Royal Society in 1911, a top distinction for a British scientist. He received the Longstaff Prize in 1924, the Davy Medal and the Liversidge Award both in 1928, and honorary degrees from various universities. These awards recognized his research and his role in developing physical chemistry as a prominent field in British universities.

Even in his later years, Donnan stayed intellectually active and connected with the scientific community well after retiring. He died on 16 December 1956 in Canterbury, England, at eighty-six. His life covered a time of major changes in chemistry, from organizing physical chemistry in the 1890s to the start of molecular biology in the 1950s, and his work linked the physical and life sciences in ways that foresaw future developments.