A Simplified Estimation of Lactate in Normal Human Blood

We have been accustomed to estimate the lactate in blood by hemolysis in water, removal of the proteins by the method of Folin and Wu (4), treatment of the filtrate with CuSO4 and Ca(OH)2 according to Van Slyke (ll), and estimation of the lactate in the centrifugate by a modification of the aeration method of Friedemann, Cotonio, and Shaffer (6). There have been suggestions that some of the precautions usually taken are not necessary for filtrates from normal blood. For instance, several workers (2, 10) have confirmed the suggestion of Friedemann, Cotonio, and Shaffer (6) that treatment of Folin-Wu filtrates with CuSOd and Ca(OH)2 might be omitted in some cases. we have found that when normal human blood is used certain other customary steps have no effect on t,he estimated lactate, and may therefore be left out. The apparatus1 (Fig. 1) is a modified form of Wendel’s (13). It takes up small space and is less liable to break than his original form. The glass joints are all int,erchangeable. R.ubber stoppers are used at points where quick strains occur. The absorption towers are similar to Wendel’s (13). Reagents-These are all made according to Friedemann, Cotonio, and Sha,ffer (6) and Folin and Wu (4), except our sodium bisulfite, which is 5 per cent,.