INFLUENCE OF CERTAIN METALS ON THE STABILITY OF INSULIN

Small amounts of zinc, in the ratio of 0.05, 0.1 and 0.4 mgm. to 1000 units, were shown to retard the rate of deterioration of low-ash, zinc-free insulin incubated at 52°C. The addition of 1 mgm. of either cobalt, nickel or aluminum to 1000 units of insulin was observed to be very effective in preserving the physiologic activity of insulin incubated at 52°C. for at least seven weeks.