Use of microelectrodes for electrochemiluminescent detection in microfluidic devices

Abstract

Sarah J Fredrick is a senior chemistry major at Creighton University, NE, USA. She has been carrying out research in the laboratory of Dr Erin Gross of Creighton University since the fall of 2006. She has assisted in the construction and characterization of microfluidic devices for electrochemiluminescent detection methods. She will graduate in May 2009 with a B.S. in Chemistry and plans to attend graduate school to continue her studies. Microfluidic devices allow for fast detection with little reagent consumption. They also offer portability and the ability to mimic biological systems. Currently, many microfluidic devices are a hybrid of the microchip components, such as flow channels and wells, and larger instrumentation. There is a need to develop miniaturized detectors for lab-on-a-chip applications. Electrochemical detection methods have the advantage of ease of miniaturization. The electrochemical method, electrochemiluminescence, has the potential to be miniaturized and incorporated into a lab-on-a-chip device. As in other electrochemical methods, electrochemiluminescence is straightforward to miniaturize, but also possesses the sensitivity of a fluorescence detection method. In our laboratory, we have been developing carbon ink microelectrodes as the working electrode for a miniaturized electrochemiluminescence system. Since the signal is proportional to the electrode area, the challenge has been to maximize the signal-to-noise ratio and maintain low detection limits as the electrode size decreases.