C₂₅₆H₃₈₁N₆₅O₇₆S₆ (pork)

C₂₅₄H₃₇₇N₆₅O₇₅S₆ (beef)

Definition. Insulin is the natural antidiabetic hormone obtained from pork or beef pancreas and purified.

Chemical name. [Pork] Insulin; porcine insulin; CAS Reg. No. 12584-58-6.

[Beef] Insulin; bovine insulin; CAS Reg. No. 11070-73-8.

Description. A white or almost white powder; odourless.

Solubility. Practically insoluble in water, ethanol (~750 g/l) TS, and ether R; dissolves in dilute solutions of mineral acids and alkali hydroxides.

Category. Antidiabetic agent.

Storage. Insulin should be kept in a tightly closed container, protected from light, and stored at a temperature not below -20 °C.

Labelling. The designation on the container should state the animal source of the insulin; expiry date.

Additional information. Insulin is hygroscopic; it degrades in solutions of alkali hydroxides. Attention should be paid to the microbiological quality since Insulin is of natural origin.

The quality of insulin, which represents a unique case among preparations in the WHO Model List of Essential Drugs, cannot be adequately controlled by methods adopted for The International Pharmacopoeia. Therefore, it is advised to refer to methods described in other pharmacopoeias, such as those of China, Europe, Japan, UK, and USA.