GB889648A - Novel heparin process - Google Patents

Abstract

Heparin is isolated in the form of a waterinsoluble heparin complex from an aqueous animal tissue extract containing it by treating the extract with a quaternary ammonium salt having a solubility in water of at least 2%, and in which one of the valencies of the nitrogen atom of the salt carries an essentially aliphatic hydrocarbon chain of at least 8 carbon atoms. The quaternary ammonium salt may have the formula <FORM:0889648/IV (a)/1> wherein X is any anion that does not render the salt water-insoluble, e.g. chloride, bromide or sulphate, and R is the essentially aliphatic hydrocarbon chain of at least 8 carbon atoms which may be part of a heterocyclic system together with other R1 radicals and which may be interrupted by oxygen, double bonds, nitrogen and aromatic rings, and wherein the R1 radicals may be alkyl containing 1-7 carbon atoms or aralkyl, alkenyl, alkoxy, polyalkoxy, or chloroalkyl radicals. The three R1 radicals may be the same or different. Many such compounds are specified of which the chief used in the examples is a commercial-mixture containing 90% hexadecyl trimethyl ammonium chloride, 6% octadecyl trimethyl ammonium chloride, and 4% octadecenyl trimethyl ammonium chloride. The water-insoluble heparin complex thus obtained may be redissolved in a salt solution and the free heparin precipitated with a water-miscible organic solvent. The initial animal tissue may be beef small intestines, beef lung, hog duodenum, hog liver, hog intestinal mucosa and dog liver.