Dilithium sequestrene as an anticoagulant.

The variety of different anticoagulants used for blood samples has increased, but there is still need for a suitable anticoagulant for the routine estimation of sodium and potassium by flame photometry. So far the only satisfactory substance for this purpose has been the expensive calcium heparin (King and Wootton, 1956). Disodium sequestrene (Proescher, 1951 ; Hadley and Larson, 1953) and dipotassium sequestrene (Hadley and Weiss, 1955) are the most valuable of the recently introduced anticoagulants for routine haematological procedures because they preserve the morphology of leucocytes for short periods better than the ammonium and potassium oxalate mixture or heparin, and they prevent platelets clumping and preserve them. The disodium sequestrene is less satisfactory than the dipotassium salt because of its lower solubility in blood. Dilithium sequestrene was prepared and its properties as an anticoagulant were investigated. It was found to have the properties of dipotassium sequestrene in routine haematological work but could also be used in many biochemical procedures, including flame photometry. This salt had previously been investigated (Hadley and Weiss, 1955) and found to be unsatisfactory because of its low solubility.