GB735739A - Improvements in or relating to the production of heparin - Google Patents

Abstract

A crude heparin extract is mixed with a basic dye of the thiazine group, excess dye is removed from the resulting precipitate, the precipitate is then dissolved in a solvent which does not substantially affect the heparin and an electrolyte and a precipitating agent for the heparin added and the precipitated heparin recovered. The crude heparin extract may be prepared by known methods from lung or liver tissues but it is preferred to use an alkaline extract fully saturated with ammonium sulphate. Suitable dyestuffs include thionine and Azure A. The dye-heparin product may be dissolved in formamide, dimethylformamide or N-caustic soda. Electrolyte (sodium chloride) may be added to form a saturated solution in the liquid present and the heparin precipitated by addition of methanol, ethanol or acetone. The formation of the heparin dye complex may be carried out at temperatures not above 25-30 DEG C. In an example minced lung tissue is extracted with 2N caustic soda and ammonium sulphate and filtered. To the filtrate an aqueous solution of Azure A is added, the precipitate filtered off and washed with distilled water and 0.05 N hydrochloric acid to remove excess dyestuff. The washed precipitate is dissolved in formamide, and after centrifuging saturated sodium chloride and methyl alcohol added. The precipitated heparin is purified by redissolving in formamide, adding saturated sodium chloride and precipitating with methyl alcohol.