Microderivatization of anodized glassy carbon

Microelectrodes have been used to modify locally the electrochemical activity on glassy carbon electrodes. Glassy carbon was electrochemically oxidized to form an oxide layer which is inhibitory toward certain electron-transfer reactions. Activity was restored through the application of hydroxide, which was generated electrochemically at the tip of a microelectrode. With the tip positioned in close proximity to the anodized glassy carbon surface, microdomains of electrochemical activity were created in an otherwise inactive matrix. The distribution of electrochemical activity was characterized using electrochemical feedback at the microelectrode, electrogenerated chemiluminescence imaging, and electrodeposition of silver. Spatially directed activation of the glassy carbon surface was accomplished in the micrometer domain.