Carbonic Anhydrase

One Unit is determined by the electrometric method of Wilbur and Anderson (J. Biol. Chem., 176, 147 (1948)), in which the time required (in seconds) for a saturated CO2 solution to lower the pH of 0.02M Tris-HCl buffer from 8.3 to 6.3, at 0-4°C is determined.