Abstract
The changes in the pyruvate content of blood after the sample has been drawn can be prevented by collecting the blood in tubes containing a dried citrate buffer, pH 4.0, together with NaF and cetyltrimethylarnmonium bromide, which acts as a hemolytic agent. The detn. of pyruvic acid in blood samples, thus treated, can then be carried out by the 2:4-dinitro-phenyl-hydrazone method.