Student-Developed Analytical Approach for Element Determination in Dietary Supplements

We present a new laboratory experiment in which students use a nitrogen microwave inductively coupled atmospheric-pressure plasma optical emission spectrometer (MICAP-OES) to determine several elements in dietary supplements. Unlike most other quantitative analytical lab experiments, this experiment required students to develop and carry out their own approaches to a given analytical task based on a previous lecture course on quantitative element analysis. Experimental details were not provided to the students. Appropriate procedures included dissolving the samples, as well as acid digestions. Students were able to contrive and perform the analysis within the given time frame of 4 h. We also show various ways in which the experiment can be adapted to provide different content emphases on sample preparation, calibration, use of internal standards, and spectral interference. An evaluation indicated that this experiment was well received by students but students also asked for a more detailed handout.