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SCIENTIST OF
WORLD RENOWN
In studying bile acids, their chemical compo-
sition, and the shares of the individual elements
in the compounds, Pregl was confronted by pra-
ctical problems such as how to procure suffici-
ent amounts of biological material for analysis.
The analytical methods at the time required
about 400 mg of compound, which he would
obtain by processing roughly 100 kg of bile. For
a comprehensive analysis of bile acids he wou-
ld need 2-3 g of compound derived from 500-
800 kg of bile! He therefore developed a new
method that produced accurate results using
much smaller quantities: he achieved this by
scaling down the equipment and improving the
accuracy of the scale to within a millionth of a
gram, which reduced the necessary amount of
experimental matter, accelerated procedures,
and reduced costs. In practice, this meant that
as little as 150 mg of isolated chemically pure
matter sufficed to identify more than one ele-
ment in a compound. His method of quantitati-
ve organic analysis was an achievement deser-
ving of the Nobel Prize in Chemistry.
50
The cover of his book Quantitative Organic Microanalysis published in 1917.