Radical Quenching of 1,1-Diphenyl-2-picrylhydrazyl: A Spectrometric Determination of Antioxidant Behavior
John M. Berger, Roshniben J. Rana, Hira Javeed, Iqra Javeed, and Sandi L. Schulien
Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ 07043
Radical chemistry is a fundamental subject of undergraduate organic chemistry. While well described in organic textbooks, laboratory manuals rarely address this topic, focusing instead on syntheses using polar reactions. Herein, we describe a colorimetric assay using the persistent radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) to measure the antioxidant activity of common antioxidants in one (3 hour) lab period. While the laboratory procedures are designed for a second-year organic laboratory environment, minor modifications to either the experiment or the supplemental material would make this suitable for more or less advanced courses. This exercise is particularly appropriate for a course geared for nutrition or food science majors.
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