By the spring of 1942, Pauling's participation in the oxygen meter project had waned.
With Arnold Beckman in charge of producing the instruments and Wood and Sturdivant
managing most of the daily details, much of the earlier strain from that project was
gone. Pauling had focused so much of his time and energy on the oxygen meter that,
with the project off his hands, he found himself relatively unoccupied. Then, shortly
after the bombing of Pearl Harbor and the subsequent U.S. declaration of war, a call
went out through the ranks of the OSRD. As America's role in the war began to escalate
in earnest, it was clear that soldiers were going to be sustaining injuries and would
be in need of blood transfusions. The demand for blood would soon outstrip the available
supply and the government was looking to scientists for help. As it so happened,
Pauling had an idea.
In 1941 Linus Pauling had begun a limited program of study on bovine and human gamma-globulin,
a project stemming from his interest in the manufacture of antibodies. Pauling initiated
experimentation with the preparation of antisera - blood sera containing defensive
antibodies - and in the process quickly became an authority on the chemistry of human
blood and hemoglobin. This experience had given him insight into a potential method
for creating a blood substitute. By April 1942 Pauling had submitted a contract proposal
to the Committee on Medical Research. Entitled "The Chemical Treatment of Protein
Solutions in the Attempt to Find a Substitute for Human Serum for Transfusions," the
proposal outlined a plan to develop a gelatin-based substance which could be used
as a plasma substitute. The project, if successful, would produce a synthetic material
that would take the place of donated human blood plasma in transfusions, aiding Allied
soldiers when America's peacetime blood reserves ran low.
The CMR accepted Pauling's proposal and within two weeks Pauling had assembled a group
of researchers, including doctors Joseph B. Koepfli and Dan H. Campbell. After securing materials from Edward Cohn and other American-based scientists, the
team was ready to begin.