Carey L. Scortichini - Sanford MI
Janeth M. Bartlett - Midland MI
The Dow Chemical Company - Midland MI
An electrolytic cell for the labeling of proteins, peptides and other organic molecules employs a cathodic half cell and an anodic half cell, where a porous working electrode is located in one half cell and a counter electrode is located in the other of the half cell, the two half cells being divided by a separator. A reference electrode located in the half cell containing the working electrode, and placed outside the current path between the working electrode and the counter electrode confers precise control of the working electrode potential, which allows the maximum rate of labeling to be achieved while minimizing oxidative damage to the protein, peptide or organic molecules. Saturation of the working electrode with non-radioactive label coupled with a ratio of working electrode surface area to volume of half cell containing the working electrode between 0. 001 cm. sup. -1 to about 10 cm. sup. -1 minimizes the problem of loss of activity of radiolabel due to adsorption on the working electrode.