Izaak Kolthoff

Izaak Maurits Kolthoff ( born February 11, 1894 in Almelo, † March 4, 1993 in Saint Paul, Minnesota) was a Dutch- American chemist who was considered one of the fathers of analytical chemistry in the United States. He also dealt with physical chemistry.

Kolthoff studied from 1911 Pharmacy at the University of Utrecht with the diploma in 1915. Thereafter, he continued to study chemistry in 1918 and his doctorate ( after Latin and Greek were dropped as a prerequisite ). At this time he had published more than 30 works. He wa 1917-1927 curator at the Pharmaceutical Institute in 1924 lecturer in electrochemistry in Utrecht. After guest lectures in the United States in 1924, where he also undertook research on synthetic rubber production, he became in 1927 professor of analytical chemistry at the University of Minnesota. He remained there and was scientifically active even after his retirement in 1962 until the 1980s.

He examined neutralization and led a 1915 buffer solutions and examined from 1918 redox titrations. He was also a pioneer of Conductometry, the study of the conductivity of solutions for the concentration determination. In 1920, he introduced the term potentiometric titration. In the U.S., he examined gravimetric analysis method, turned amperometry on organo-sulfur compounds on, developed a kinetic method for internal and external double bonds in polymers to distinguish, examined reactions in non-aqueous solutions.

He was a member of the National Academy of Sciences and the American Academy of Arts and Sciences. He was also several honorary doctorate ( University of Chicago, Brandeis University, University of Groningen, Hebrew University ) and in 1947 in the Netherlands Commander of the Order of Oranje -Nassau. He received the Robert Boyle Medal of the Royal Society of Chemistry, the Willard Gibbs Medal and the William H. Nichols Medal.


  • The use of color Indicators: their use in neutralization and analysis in the colorimetric determination of hydrogen ion concentration, Springer Verlag 1926 4th edition with Harry Gold fish as acid-base Indicators: its application to the colorimetric determination of hydrogen ion concentration, Springer Verlag 1932
  • English Translation: Indicators; Their use in quantitative analysis and in the colorimetric determination of hydrogen -ion concentration, Wiley 1926
  • English translation of Volumetric Analysis 1928, new edition in three volumes from 1942 to 1957 with VA Stenger, G. Matsuyama, R. Belcher at Interscience
  • First as: Polarography: polarographic analysis and voltammetry, amperometric titration, Interscience 1941
  • English Translation: The Colorimetric and Potentiometric Determination of pH, 1931