Diazonium Modification of Carbon Surfaces for Use in Biosensors

Abstract

By Catherine Peters, Chemistry-ACS

Advisor: Ryan White

Presentation ID: AM_D06

Abstract: In the production of electrochemical aptamer-based sensors, much work has been done on gold surfaces. The aptamer can be attached to the gold substrate in a simple process which requires little effort from the researcher. The difference in chemistry between the gold surface and the more robust carbon surface, however, is significant. It is much more difficult to modify the carbon surface to allow the attachment of the DNA aptamer. One common method is to use a diazonium salt which, in the presence of an applied current, forms a radical that can then bind irreversibly to the carbon substrate. The density of the diazonium compound grafted to the surface can be controlled through both deposition time and solution concentration, and the formation of a monolayer can theoretically be encouraged through the use of a radical scavenger.