Sam Ruben
Encyclopedia
Samuel Ruben the son of Herschel and Frieda Penn Rubenstein – the name was officially shortened to Ruben in 1930. Young Sam developed a friendship with neighbor Jack Dempsey
and became involved with a local boys' boxing club and later, when the family moved across the Bay to Berkeley
, he was a successful basketball player at Berkeley High School (Berkeley, California). After achieving his B.S. in Chemistry
at the University of California, Berkeley
, he continued his studies there and was awarded a Ph.D. in Physical Chemistry
in May 1938. He was immediately appointed Instructor in the Chemistry Department, and became an Assistant Professor in 1941.
Sam and colleague Martin Kamen
, a University of Chicago
Ph.D. and researcher in chemistry
and nuclear physics
working under Ernest O. Lawrence at the Berkeley Radiation Laboratory, set out to elucidate the path of carbon in photosynthesis
by incorporating the short-lived radioactive isotope Carbon-11 (11CO2) in their many experiments between 1938 and 1942. Aided by the concepts and collaboration of C. B. van Niel, at Stanford University
’s Hopkins Marine Station
, it became clear to them that reduction of CO2 can occur in the dark and may involve processes similar to bacterial systems. This interpretation challenged the century-old Adolf von Baeyer
theory of photochemical reduction of CO2 adsorbed on chlorophyll
which had guided decades of effort by Richard Willstätter
, A. Stoll, and many others in vain searches for formaldehyde
.
In hundreds of experiments with Carbon-11 produced from deuterons and Boron-10 by Martin Kamen
in the Radiation Laboratory’s 37-inch cyclotron
, Ruben and Kamen, with collaborators from botany
, microbiology
, physiology
and organic chemistry
, pursued the path of carbon dioxide in plants, algae, and bacteria. Their results, confused by absorption of the products on proteinaceous residues, initially failed to reveal the path of carbon
in photosynthesis
but succeeded in exciting the interest of scientists worldwide in the search and revelation of metabolic processes, beginning a revolution in biochemistry
and medicine.
Ruben’s experiments using 'heavy water', H2O18, to yield 18O2 gas had shown that the oxygen
gas produced in photosynthesis
comes from water. With nuclear physicists' tenuous prediction of a "long lived radioactive carbon isotope,” Ruben and Kamen pursued several routes that could lead to identification of the Carbon-14
isotope. After several failed attempts, Martin Kamen
collected the results of a 120-hour cyclotron
bombardment of graphite and trudged in the rain with it to the “Rat House,” adjacent both to the Chemistry Department and to the cyclotron
, and Sam Ruben's desk. At 8 AM, February 27, 1940, Sam Ruben demonstrated unequivocally the radioactivity was from Carbon-14
.
The weak energy of Carbon-14
made measurement tedious. So tedious that no tracer experiments with C-14 were done until 1942 when Sam Ruben gave all his barium carbonate-C14 to young Chemistry Department faculty member Andrew Benson
who began his long series of 14CO2 fixation experiments to determine the path of carbon in photosynthesis
. Only in 1949 did chemist Willard Libby
use it to invent radiocarbon dating
.
Ruben's recruitment for research in the World War II wartime effort led him to interest in the mechanism of phosgene
as a poisonous gas. With C-11 phosgene (11COCl2) prepared by Benson, they studied the combination of phosgene
with lung proteins. Following Benson's departure from Berkeley in July 1943, Ruben died September 28, 1943 after a disastrous exposure to phosgene
in a laboratory accident the preceding day.
Sam Ruben married Helena Collins West, a fellow chemistry student, during his final semester as an undergraduate at UC Berkeley, on September 28, 1935. They had three children, Dana West Ruben (born November 11, 1938), George Collins Ruben (born April 29, 1941, and Connie Mae Ruben Fatt (born June 18, 1943).
Jack Dempsey
William Harrison "Jack" Dempsey was an American boxer who held the world heavyweight title from 1919 to 1926. Dempsey's aggressive style and exceptional punching power made him one of the most popular boxers in history. Many of his fights set financial and attendance records, including the first...
and became involved with a local boys' boxing club and later, when the family moved across the Bay to Berkeley
Berkeley, California
Berkeley is a city on the east shore of the San Francisco Bay in Northern California, United States. Its neighbors to the south are the cities of Oakland and Emeryville. To the north is the city of Albany and the unincorporated community of Kensington...
, he was a successful basketball player at Berkeley High School (Berkeley, California). After achieving his B.S. in Chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
at the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
, he continued his studies there and was awarded a Ph.D. in Physical Chemistry
Physical chemistry
Physical chemistry is the study of macroscopic, atomic, subatomic, and particulate phenomena in chemical systems in terms of physical laws and concepts...
in May 1938. He was immediately appointed Instructor in the Chemistry Department, and became an Assistant Professor in 1941.
Sam and colleague Martin Kamen
Martin Kamen
Martin David Kamen , a physicist inside the Manhattan project. Together with Sam Ruben, he co-discovered the isotope carbon-14 on February 27, 1940, at the University of California Radiation Laboratory, Berkeley....
, a University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...
Ph.D. and researcher in chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
and nuclear physics
Nuclear physics
Nuclear physics is the field of physics that studies the building blocks and interactions of atomic nuclei. The most commonly known applications of nuclear physics are nuclear power generation and nuclear weapons technology, but the research has provided application in many fields, including those...
working under Ernest O. Lawrence at the Berkeley Radiation Laboratory, set out to elucidate the path of carbon in photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
by incorporating the short-lived radioactive isotope Carbon-11 (11CO2) in their many experiments between 1938 and 1942. Aided by the concepts and collaboration of C. B. van Niel, at Stanford University
Stanford University
The Leland Stanford Junior University, commonly referred to as Stanford University or Stanford, is a private research university on an campus located near Palo Alto, California. It is situated in the northwestern Santa Clara Valley on the San Francisco Peninsula, approximately northwest of San...
’s Hopkins Marine Station
Hopkins Marine Station
Hopkins Marine Station is the marine laboratory of Stanford University. It is located ninety miles south of the university's main campus, in Pacific Grove, California on the Monterey Peninsula, adjacent to the Monterey Bay Aquarium. It is home to nine research laboratories and a fluctuating...
, it became clear to them that reduction of CO2 can occur in the dark and may involve processes similar to bacterial systems. This interpretation challenged the century-old Adolf von Baeyer
Adolf von Baeyer
Johann Friedrich Wilhelm Adolf von Baeyer was a German chemist who synthesized indigo, and was the 1905 recipient of the Nobel Prize in Chemistry. Born in Berlin, he initially studied mathematics and physics at Berlin University before moving to Heidelberg to study chemistry with Robert Bunsen...
theory of photochemical reduction of CO2 adsorbed on chlorophyll
Chlorophyll
Chlorophyll is a green pigment found in almost all plants, algae, and cyanobacteria. Its name is derived from the Greek words χλωρος, chloros and φύλλον, phyllon . Chlorophyll is an extremely important biomolecule, critical in photosynthesis, which allows plants to obtain energy from light...
which had guided decades of effort by Richard Willstätter
Richard Willstätter
Richard Martin Willstätter was a German organic chemist whose study of the structure of plant pigments, chlorophyll included, won him the 1915 Nobel Prize for Chemistry. Willstätter invented paper chromatography independently of Mikhail Tsvet.-Biography:Willstätter was born in to a Jewish family...
, A. Stoll, and many others in vain searches for formaldehyde
Formaldehyde
Formaldehyde is an organic compound with the formula CH2O. It is the simplest aldehyde, hence its systematic name methanal.Formaldehyde is a colorless gas with a characteristic pungent odor. It is an important precursor to many other chemical compounds, especially for polymers...
.
In hundreds of experiments with Carbon-11 produced from deuterons and Boron-10 by Martin Kamen
Martin Kamen
Martin David Kamen , a physicist inside the Manhattan project. Together with Sam Ruben, he co-discovered the isotope carbon-14 on February 27, 1940, at the University of California Radiation Laboratory, Berkeley....
in the Radiation Laboratory’s 37-inch cyclotron
Cyclotron
In technology, a cyclotron is a type of particle accelerator. In physics, the cyclotron frequency or gyrofrequency is the frequency of a charged particle moving perpendicularly to the direction of a uniform magnetic field, i.e. a magnetic field of constant magnitude and direction...
, Ruben and Kamen, with collaborators from botany
Botany
Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses...
, microbiology
Microbiology
Microbiology is the study of microorganisms, which are defined as any microscopic organism that comprises either a single cell , cell clusters or no cell at all . This includes eukaryotes, such as fungi and protists, and prokaryotes...
, physiology
Physiology
Physiology is the science of the function of living systems. This includes how organisms, organ systems, organs, cells, and bio-molecules carry out the chemical or physical functions that exist in a living system. The highest honor awarded in physiology is the Nobel Prize in Physiology or...
and organic chemistry
Organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds, hydrocarbons, and their derivatives...
, pursued the path of carbon dioxide in plants, algae, and bacteria. Their results, confused by absorption of the products on proteinaceous residues, initially failed to reveal the path of carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
in photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
but succeeded in exciting the interest of scientists worldwide in the search and revelation of metabolic processes, beginning a revolution in biochemistry
Biochemistry
Biochemistry, sometimes called biological chemistry, is the study of chemical processes in living organisms, including, but not limited to, living matter. Biochemistry governs all living organisms and living processes...
and medicine.
Ruben’s experiments using 'heavy water', H2O18, to yield 18O2 gas had shown that the oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
gas produced in photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
comes from water. With nuclear physicists' tenuous prediction of a "long lived radioactive carbon isotope,” Ruben and Kamen pursued several routes that could lead to identification of the Carbon-14
Carbon-14
Carbon-14, 14C, or radiocarbon, is a radioactive isotope of carbon with a nucleus containing 6 protons and 8 neutrons. Its presence in organic materials is the basis of the radiocarbon dating method pioneered by Willard Libby and colleagues , to date archaeological, geological, and hydrogeological...
isotope. After several failed attempts, Martin Kamen
Martin Kamen
Martin David Kamen , a physicist inside the Manhattan project. Together with Sam Ruben, he co-discovered the isotope carbon-14 on February 27, 1940, at the University of California Radiation Laboratory, Berkeley....
collected the results of a 120-hour cyclotron
Cyclotron
In technology, a cyclotron is a type of particle accelerator. In physics, the cyclotron frequency or gyrofrequency is the frequency of a charged particle moving perpendicularly to the direction of a uniform magnetic field, i.e. a magnetic field of constant magnitude and direction...
bombardment of graphite and trudged in the rain with it to the “Rat House,” adjacent both to the Chemistry Department and to the cyclotron
Cyclotron
In technology, a cyclotron is a type of particle accelerator. In physics, the cyclotron frequency or gyrofrequency is the frequency of a charged particle moving perpendicularly to the direction of a uniform magnetic field, i.e. a magnetic field of constant magnitude and direction...
, and Sam Ruben's desk. At 8 AM, February 27, 1940, Sam Ruben demonstrated unequivocally the radioactivity was from Carbon-14
Carbon-14
Carbon-14, 14C, or radiocarbon, is a radioactive isotope of carbon with a nucleus containing 6 protons and 8 neutrons. Its presence in organic materials is the basis of the radiocarbon dating method pioneered by Willard Libby and colleagues , to date archaeological, geological, and hydrogeological...
.
The weak energy of Carbon-14
Carbon-14
Carbon-14, 14C, or radiocarbon, is a radioactive isotope of carbon with a nucleus containing 6 protons and 8 neutrons. Its presence in organic materials is the basis of the radiocarbon dating method pioneered by Willard Libby and colleagues , to date archaeological, geological, and hydrogeological...
made measurement tedious. So tedious that no tracer experiments with C-14 were done until 1942 when Sam Ruben gave all his barium carbonate-C14 to young Chemistry Department faculty member Andrew Benson
Andrew Benson
Andrew Alm Benson is an American biologist and a professor of biology at the University of California, San Diego until his retirement in 1989...
who began his long series of 14CO2 fixation experiments to determine the path of carbon in photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
. Only in 1949 did chemist Willard Libby
Willard Libby
Willard Frank Libby was an American physical chemist noted for his role in the 1949 development of radiocarbon dating, a process which revolutionized archaeology....
use it to invent radiocarbon dating
Radiocarbon dating
Radiocarbon dating is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" ,...
.
Ruben's recruitment for research in the World War II wartime effort led him to interest in the mechanism of phosgene
Phosgene
Phosgene is the chemical compound with the formula COCl2. This colorless gas gained infamy as a chemical weapon during World War I. It is also a valued industrial reagent and building block in synthesis of pharmaceuticals and other organic compounds. In low concentrations, its odor resembles...
as a poisonous gas. With C-11 phosgene (11COCl2) prepared by Benson, they studied the combination of phosgene
Phosgene
Phosgene is the chemical compound with the formula COCl2. This colorless gas gained infamy as a chemical weapon during World War I. It is also a valued industrial reagent and building block in synthesis of pharmaceuticals and other organic compounds. In low concentrations, its odor resembles...
with lung proteins. Following Benson's departure from Berkeley in July 1943, Ruben died September 28, 1943 after a disastrous exposure to phosgene
Phosgene
Phosgene is the chemical compound with the formula COCl2. This colorless gas gained infamy as a chemical weapon during World War I. It is also a valued industrial reagent and building block in synthesis of pharmaceuticals and other organic compounds. In low concentrations, its odor resembles...
in a laboratory accident the preceding day.
Sam Ruben married Helena Collins West, a fellow chemistry student, during his final semester as an undergraduate at UC Berkeley, on September 28, 1935. They had three children, Dana West Ruben (born November 11, 1938), George Collins Ruben (born April 29, 1941, and Connie Mae Ruben Fatt (born June 18, 1943).