The atmosphere at Caltech changed during World War II. Fewer young men attended Caltech
during the war years and many members of Caltech's staff focused their attention on
projects that aided the war effort. Some chose to leave Caltech, however Pauling remained
in Pasadena while conducting many research projects for the United States government.
He aided the war effort by continuing to work on immunology and by branching out into
new areas that built upon his previous endeavors. Two of his projects involved hemoglobin.
Pauling tried to find a serum that could substitute for blood and be used for blood
transfusions. Working for the Office of Scientific Research and Development (OSRD),
Pauling and Campbell, one of his collaborators on immunological research, developed
a successful serum substitute called oxypolygelatin. Oxypolygelatin was not used,
however, because by 1943 there were enough blood donors to make using the serum unnecessary.
Even though the government lost interest in oxypolygelatin, Pauling did not. During
the 1940s, he, Campbell, and others continued to work on the blood substitute and
improved the gelatin. In December 1946 Pauling, Campbell, and another colleague submitted
a patent application for Oxypolygelatin.
Pauling also developed a spectrophotometric device that determined the amount of carbon
monoxide in the air based upon the concentration of carbon monoxide in a sample of
blood. He made this instrument for airplanes and tanks on the request of the National
Defense Research Committee. Spectrophotometry, the technique used for the apparatus,
yields concentration information through absorption spectra. In the end Pauling found
that the device was unsuitable for use because of its bulk, sensitivity and the instability
of the reagent, oxyhemoglobin.
The United States government acknowledged Pauling for his scientific work that aided
the war. The most prestigious award he received was the Medal for Merit from President
Harry S. Truman, who called Pauling's work "brilliant."