Our research interests center around microelectrodes and their use to probe complex chemical and biochemical phenomena. Ultramicroelectrodes are chemical sensors with micron or smaller dimensions. The sensors are unique in that they enable electrochemical measurements in a number of unusual domains including the local microenvironment next to a biological cell, solutions of high resistance such as supercritical fluids, and the transient observation of chemical entities with nanosecond lifetimes.
We are using these devices are being used to explore several different areas. One application includes the generation of excited state, light emitting species from reagents generated electrochemically. The resulting microscopic light source is remarkably intense, and can be used as an illuminator for microscopy or as an indicator for analytical detection.

A second application concerns a study of exocytosis at single biological cells. Exocytosis is a primary mechanism whereby cells secrete chemical messengers into the surrounding solution. Ultramicroelectrodes can monitor the temporal profile of exocytosis as it occurs providing unique insight into the rate determining steps. In addition, the electrodes can be used as in vivo sensors of neurotransmitters in the intact brain of a living animal. This enables the unique opportunity to examine neurochemical changes with subsecond time resolution, and to correlate these with the animals behavior.