Preparation of improved thromboplastin

Claim 1

A PROCESS FOR THE PREPARATION OF THROMBOPLASTIC MATERIAL COMPRISING THE STEPS OF: SUSPENDING IN 0.85 PERCENT AQUEOUS SODIUM CHLORIDE SOLUTION A FIRST THOMBOPLASTIC MATERIAL, COMPRISING A FINELY DIVIDED TISSUE RESIDUE RESULTING FROM THE EXTERACTION OF RABBIT BRAIN TISSUE WITH ACETONE; AND A SECOND THROMBOPLASTIC MATERIAL, RESULTING FROM THE EXTRACTION OF FINELY DICIDED RABBIT TISSUE. SELECTED FROM THE CLASS CONSISTING OF BRAIN AND LUNG TISSUE, WITH AN AQUEOUS SOLUTION BUFFERED AT A PH WITHIN THE RANGE OF 5-8 AND CONTAINING AN ALCOHOL, SELECTED FROM THE GROUP CONSISTING OF METHANOL AND ETHANOL AND MIXTURES THEREOF, IN THE AMOUNT OF 5-20 PERCENT BY VOLUME AND 0.01-6.0 PERCENT BY WEIGHT OF AN AMINO ACID HAVING NOT MORE THAN NINE CARBON ATOMS, SEPARATION OF THE FINELY DIVIDED TISSUE FROM THE EXTRACTING SOLUTION AND DIALYSIS OF THE EXTRACTING SOLUTION AGAINST DISTILLED WATER THE AMOUNT IN EACH TEN CC. PORTION OF SUSPENSION OF THE FIRST THROMBOPLASTIC MATERIAL BEING 50-200 MILLIGRAMS AND OF THE SECOND THROMBOPLASTIC MATERIAL 20-200 MILLIGRAMS; INCUBATING THE SUSPENSION IN SODIUM CHLORIDE SOLUTION OF THE FIRST AND SECOND THROMBAPLASTIC MATERIALS FOR ABOUT TWENTY MINUTES AT 50*C., CENTRIFUGING THE INCUBATED SUSPENSION, ADDING AQUEOUS CALCIUM CHLORIDE SOLUTION TO THE SUPERNATANT FROM THE CENTRIFUGATIN IN AN AMOUNT SUCH THAT THE CALCIUM ION CONCENTRATION THEREIN IS 0.004-0.015 MOLAR AND CENTRIFUGING TO PROVIDE A SUPERNATANT CONTAINING A HIGHLY ACTIVE THROMBOPLASTIC MATERIAL.