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The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 22 (2017) pp 100-103

Determining the Total Antioxidant Capacity in Blackberries Using Cyclic Voltammetry: A Quantitative Analysis Laboratory Experiment

Andrew J. King and Fei Yan*

Department of Chemistry and Biochemistry, North Carolina Central University, Durham, North Carolina 27707, fyan@nccu.edu
Received December 14, 2016. Accepted June 2, 2017.

Published: 9 June 2017

Abstract. Enabling students to experience quantitative chemical analysis concepts in a context that exemplifies real-world applications is a desirable pedagogical strategy. This experiment, developed for the undergraduate quantitative analysis laboratory, uses a cyclic voltammetry module of a MicroLab laboratory data system to determine the total antioxidant capacity expressed as the amount of gallic acid in blackberries. A great linear correlation (R2 = 0.99) was found between the gallic acid concentration ranging from 0.1–10.0 mM and the total area under a quasi-reversible oxidation of gallic acid on disposable screen-printed carbon electrodes. Two types of blackberries (i.e., regular and organic) were tested in triplicate, and their antioxidant properties were expressed as a weight of gallic acid in milligrams per 1 g of raw berry samples.

Key Words: Laboratories and Demonstrations; quantitative analysis; analytical chemistry, cyclic voltammetry, antioxidants, gallic acid, hands-on learning/manipulative

(*) Corresponding author. (E-mail: fyan@nccu.edu)

Article in PDF format (203 KB) HTML format

Supporting Materials:

A student handout which consists of the detailed procedure and data sheets is available on the publisher’s website. (257 KB)



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