Preparation of a diagnostic agent for measuring the coagulability of blood
AssigneeBehringwerke Aktiengesellschaft
InventorsHeiner Trobisch, Horst Schwinn
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Abstract
A diagnostic agent containing thromboplastin sensitive to factor VII and factor X for measuring the coagulability of blood is prepared by extracting an aqueous suspension of thrombogenic tissue at pH 10 to 12, acidifying the extract, separating the extract from the tissue and adding a water-soluble calcium salt to the extract. The agent can be stabilized by adding to the extract cholanic acid and a water-soluble heavy metal-II-salt.
Claims15
A method for making a diagnostic agent for measuring the coagulability of blood, which method comprises washing a thrombogenic tissue until it is free from blood, preparing an aqueous suspension of the washed tissue containing sufficient lye to provide the suspension with a pH of from 10 to 12, extracting the tissue in the suspension at said pH for 15 minutes to 48 hours at a temperature from 30.degree. C. to 1.degree. C., whereby the shortest extraction time is correlated with the highest temperature, the longest extraction time with the lowest temperature, and values between these are correlated analogously, acidifying the aqueous suspension to impart a slightly acid pH, separating the extract from the tissue, and adding a water-soluble calcium salt to the extract.
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