HUMULIN 70/30 (70% human insulin isophane suspension and 30% human insulin injection [rDNA origin]) is a human insulin suspension. Human insulin is produced by recombinant DNA technology utilizing a non-pathogenic laboratory strain of Escherichia coli. HUMULIN 70/30 is a suspension of crystals produced from combining human insulin and protamine sulfate under appropriate conditions for crystal formation and mixing with human insulin injection. The amino acid sequence of HUMULIN 70/30 is identical to human insulin and has the empirical formula C257H383N65O77S6 with a molecular weight of 5808.
HUMULIN 70/30 is a sterile white suspension. Each milliliter of HUMULIN 70/30 contains 100 units of insulin human, 0.24 mg of protamine sulfate, 16 mg of glycerin, 3.78 mg of dibasic sodium phosphate, 1.6 mg of metacresol, 0.65 mg of phenol, zinc oxide content adjusted to provide 0.025 mg zinc ion, and Water for Injection. The pH is 7.0 to 7.8. Sodium hydroxide and/or hydrochloric acid may be added during manufacture to adjust the pH.