摘要 |
Human proinsulin in crystalline form which comprises a salt of a complex of human proinsulin and divalent zinc ion, the cation of said salt being selected from the group consisting of lithium, calcium, sodium, potassium, ammonium, magnesium, and barium. The preparation comprises (a) preparing an aqueous mixture containing from about 5 to about 50 mg/ml human proinsulin, from about 0.1 to about 5 mg/ml of a phenolic substance, from about 0.03 to about 0.6 milliequivalents/ml of a salt of a cation selected from the group consisting of lithium, calcium, sodium, potassium, ammonium, magnesium, and barium, and from about 0.2 to about 5 milliequivalents of Zn<+><2> cation; (b) adjusting the aqueous mixture to a pH in the range of from about 5.4 to about 6.5; (c) allowing crystal formation to occur; and (d) recovering crystalline human proinsulin from the aqueous mixture. |