heparin tubes for blood collection

Blood collection tubes (purple head tubes) containing ethylenediaminetetraacetic acid (EDTA) and its salts: EDTA is an amino polycarboxylic acid that can effectively chelate calcium ions in the blood. The removal of calcium from the reaction site will prevent and terminate the endogenous or extrinsic coagulation process, thereby preventing blood coagulation. Compared with other anticoagulants, it has less effect on blood cell agglutination and blood cell morphology, and can inhibit Aggregation of platelets, suitable for general hematology tests. The pH of EDTA solution is highly dependent on salts, and low pH can make cells swell.EDTA2K2 can slightly swell the volume of red blood cells, and the mean platelet volume (MPV) is very unstable in a short time after blood collection, and tends to be stable after half an hour. EDTA2K2 reduces calcium and magnesium, and at the same time reduces creatine kinase (CK) and alkaline phosphatase (ALP), which require these metal ions for the determination of these enzymes; the optimal concentration of EDTA2K3 is 1.5 mg/ml, if the blood is low When the concentration of EDTA increases, neutrophils will swell and lobules disappear, platelets will swell and disintegrate, and fragments of normal platelet size will be produced, which will cause errors in the analysis results. Due to the strong chelating effect of calcium, EDTA makes adenosine diphosphate (ADP) unable to cause platelet aggregation. In addition, EDTA can inhibit or interfere with the polymerization of fibrin monomers during the formation of fibrin clots, so it is not suitable for blood coagulation and platelet function tests. It is also not suitable for the determination of calcium, potassium, sodium and nitrogenous substances. The anticoagulant recommended by the International Committee for Standardization of Hematology (ICSH) is EDTA2K2. There is no significant change between EDTA2Na2 and EDTA2K2, but its solubility is low and the anticoagulation speed is slow, so it is not suitable for peripheral blood anticoagulation. The peripheral blood of EDTA anticoagulation should also be measured after 15 minutes, otherwise the platelets will temporarily aggregate, which will make the platelets falsely decrease, the white blood cells falsely increase, and the histogram will be abnormal.