Glucose determination in beverages using carbon nanotube modified biosensor: an experiment for the undergraduate laboratory
We describe a versatile method for students to fabricate carbon nanotube-based enzyme-modified biosensor electrodes using a layer-by-layer electrostatic self-assembly procedure. Amperometric experiments employing a simple three-electrode cell enabled sensitive and selective determination of glucose in various commercially produced beverages familiar to students. The method was optimized with respect to various parameters, and the results compared very well with standard methods used for glucose determination. The procedure is versatile, robust, and relatively inexpensive. It can be performed by undergraduate students as was demonstrated by the good results obtained by the upper-level instrumental analysis class. The experiment can easily be integrated into laboratory classes for analytical chemistry, biotechnology, or biochemistry students to demonstrate important principles and techniques of nanoscale science, materials science, biochemistry, electrochemistry, and sensor technology.