Compound of Sodium Fluoride and Anticoagulant Tube aims to obtain highly stable plasma for blood glucose testing. Sodium Fluoride is a kind of inhibitor of glucose degradation, it has the function of repressing glucose metabollsm and degradation. Optional Anticoagulant are Potassium Oxalate, EDTA and Heparin, they could prevent blood coagulation and avoid blood hemolysis. The particular compound additive realise that blood glucose specimen could be cold storage for a long time.