Patent GB-887395-A (GB)
Title: A method of fractionating protein solutions
IPC: C07D401/14
Filed: 1959-10-26
Abstract: Protein fractions are obtained by adding to a protein solution a quinoline compound having the structural formula <FORM:0887395/IV (b)/1> wherein X represents a bivalent organic radical containing at least two nitrogen atoms, each of the quinolyl radicals being attached to a nitrogen atom of radical X; R1, R11, R2, R12, R3 and R13 represent hydrogen, lower alkyl or substituted or unsubsti uted amino groups, and A represents an anion; and removing part of the protein as a precipitate.  Radical X may be -NH.CO.NH-, -NH.CO.CH2.NH-, -NH.CO.CH2.CO.NH-, or <FORM:0887395/IV (b)/2> The quinoline compound may be added in the form of a solution, e.g. an aqueous solution, having a concentration of from 0.1% to 1.0% by weight, e.g. about 0.4%, and having a pH from 1.9 to 5.7. Quinoline compounds specified are N,N1 - di - (2 - methyl - 4 - amino - quinolyl - 6)-ureido-dihydrochloride, or -dichloromethylate, N, N1 - di - (2 - methyl - 4 - amino - quinolyl - 6) - amino-acetic acid amide -dihydrochloride, -triamino-triazine-sulphate or -malonic acid diamide-dihydrochloride; N-(2-aminoquinolyl-6)-N1-quinolyl-ureido-dihydrochloride. The protein solution may be human or animal blood sera, pleural exudates, ascites and solutions of plant or vegetable origin. Substantially pure gamma-globulin may be isolated by addition of an amount of quinoline compound equivalent to 32 to 40 parts by volume, e.g. about 36 parts, of a 0.4% by weight aqueous solution of the compound per 10 parts by volume of human blood serum.  A mixture of beta- and gamma-globulins may be isolated by the addition of an amount of quinoline compound equivalent to 24 to 32 parts by volume of a 0.4% by weight aqueous solution of the compound per 10 parts by volume of human blood serum. The addition of smaller amounts of the quinoline compounds makes possible the separation from the serum of a mixture consisting of albumin and alpha-, beta- and gamma-globulins.  Anion A is usually monovalent or bivalent but others, e.g. the phosphate anions, may be used.ALSO:Serum fractions are obtained by adding to a solution of human or animal blood sera a quinoline compound having the structural formula <FORM:0887395/VI/1> wherein X represents a bivalent organic radical containing at least two nitrogen atoms, each of the quinolyl radicals being attached to a nitrogen atom of radical X; R1, R11, R2, R12, R3 and R13 represent hydrogen, lower alkyl or substituted or unsubstituted amino groups, and A represents an anion; and removing part of the serum as a precipitate.  Radical X may be -NH.CO.NH-, -NH.CO.CH2.NH-, -NH.CO.CH2.CO.NH-, or <FORM:0887395/VI/2> The quinoline compound may be added in the form of a solution, e.g. an aqueous solution, having a concentration of from 0.1 to 1.0% by weight, e.g. about 0.4% and having a pH from 1.9 to 5.7. Anion A is usually monovalent or bivalent but others e.g. the phosphate ions, may be used.  Quinoline compounds specified are N,N1 - di - (2 - methyl - 4 - amino - quinolyl - 6) - ureido-dihydrochloride or -dichloromethylate; N,N1 - di - (2 - methyl - 4 - amino - quinolyl - 6) - amino acetic acid amide-dihydrochloride, -triamino - triazine - sulphate or -malonic acid diamide - dihydrochloride; N - (2 - amino - quinolyl - 6) - N1 - quinolyl - ureido - dihydro - chloride. Substantially pure gamma globulin and a mixture of beta and gamma globulins may be isolated by addition of an amount of quinoline compound equivalent to 32 to 40 parts by volume, e.g. about 36 parts, and 24 to 32 parts by volume, respectively, of a 0.4% by weight aqueous solution of the compound per 10 parts by volume of human blood serum.  The addition of smaller amounts of the quinoline compound makes possible the separation from the serum of a mixture consisting of albumin and alpha-, beta- and gamma-globulins.  Protein fractions may also be obtained by addition of the quinoline compound to pleural exudates or ascites.