Determination of l -Ascorbic Acid in Tomato by Capillary Electrophoresis

In an undergraduate bioanalytical instrumental lab, students use capillary electrophoresis to quantify l -ascorbic acid (vitamin C) in food samples. The students are tasked to prepare standards, to obtain the calibration curves, and to determine the quantity of l -ascorbic acid in tomato samples ( Lycopersicon fruit). A discussion about the function of each component of a capillary electrophoresis instrument, the effect of experimental variables, and the use of different calibration strategies is also given. The experiment has been tested during four courses, showing that lab-activities helped students learn this instrumental technique.