glucose tubes contain sodium fluoride as a glycolysis inhibitor. The anticoagulants K3EDTA, potassium oxalate or sodium heparin prevent the blood from clotting. The citrate/citric acid buffer reduces the pH value in the sample immediately after blood collection leading to an instant stabilization of glucose. Depending on the test system, VACUETTE®
glucose tubes can also be used for lactate assays, with in most cases sodium fluoride being used in combination with potassium oxalate.