EDTA salts (ethylene diamine tetra acetic acid) are used for the anticoagulation of whole blood for haematological investigations as the cellular components of the blood are particularly well preserved by EDTA. It works as an anticoagulant as it forms complexes with metal ions such as calcium, therefore inhibiting the coagulation cascade. Anticoagulation with EDTA is irreversible. The EDTA concentration in tubes is LYBCON Vacutainer 1.8mg per ml of complete blood when the fill level is correct, as recommended by the ICSH (International Council Society of Haematology) and the CLSI (Clinical and Laboratory standards institute). The institutes recommend dipotassium EDTA salt (K EDTA) for 2 haematological investigation. K EDTA is used in 2 LYBCON Vacutainer tubes in spray dried form.