An Electrochemical Approach Coupled with Sb Microelectrode to Determine the Activities of Carbonic Anhydrase in the Plant Leaves

Abstract

The electrochemical approach coupled with Sb microelectrode was developed to determine the carbonic anhydrase activity in a wide range. The sensing response of the microelectrode had a good linear relationship between potential and pH value in barbital buffer. The temperature would not affect the linear relationship. During the determination, the open-circuit potential method was taken to monitor the whole course of the reversible conversion catalyzed by carbonic anhydrase, and then the initial part of uniform velocity from the reaction curve was chosen to calculate the reaction velocity (the time to change one unit of pH). This technique, in comparison with the conventional method was used to determine the activities of bovine red blood cells carbonic anhydrase, foliar carbonic anhydrase and extracellular carbonic anhydrase in some plants. The result showed that the electrochemical approach coupled with Sb microelectrode would obtain more credible, accurate data than the conventional method.