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The buffer, 3-[cyclohexylamino]-1-propanesulfonic acid (CAPs), and analytes n-decanophenone, flurbiprofen, mesityl oxide, naproxen, sulindac, and tolmetin may be replaced. Ideally, the lab should include a series of charged analytes of similar structure, but different hydrophobicity, a neutral marker, and a micelle marker to allow the students to use critical thinking and laboratory skills to determine capacity factor. We selected CAPs as the running buffer because it buffers at pH 10 and provides a low background current. You may choose other systems, for example other charged nonsteroidal anti-inflammatory drug. Before asking students to use different chemicals, we recommend you perform the experiments outlined in Learning Module IV with your substitute set. If you replace the sodium dodecyl sulfate with another surfactant, or change the pH of the running buffer, you may need to optimize the separation parameters to obtain an acceptable migration time.