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The Chemical Educator

ISSN: 1430-4171 (electronic version)

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Abstract Volume 19 (2014) pp 264-268

Determination of Moisture Content of Over the Counter Pharmaceuticals and Dried Powdered Food Products Using Coulometric Karl Fischer Titration: A Summer Undergraduate Research Experience at Historically Black College and University

Sayo O. Fakayode*,†, Cameron Abel, David A. Pollard

Department of Chemistry, North Carolina A&T State University, New Science Building 1601 East Market Street, Greensboro, NC 27411,; Department of Chemistry, Winston-Salem State University, Winston-Salem, NC, 27110
Received June 7, 2014. Accepted July 9, 2014.

Published: 29 August 2014

Abstract. Summer undergraduate research experience (SURE) continues to be a major pedagogical strategy to generate the students’ excitement, stimulate scientific research curiosity, and to promote students’ critical thinking in science, technology, engineering, and mathematics (STEM). Herein, the result of a six week intensive SURE project, involving the determination of the moisture content of selected over-the-counter (OTC)-pharmaceuticals and dried powdered foods using coulometric Karl Fischer titration (KFT) to promote underrepresented minority (URM) student learning in STEM is reported. The OTC-pharmaceuticals and food samples used for the study were purchased from local drug and grocery stores. The SURE project was conducted in a guided inquiry laboratory experiment (GILE) format to promote the students’ critical thinking and problem solving skills. An average moisture content ranging between 0.86 ± 0.09% and 10.15 ± 2.17% was obtained for the OTC-pharmaceuticals. However, the moisture content obtained in the food items ranged between 1.05 ± 0.02 % and 4.29 ± 0.43%. Overall, the percentage of moisture content determined in the samples was very low, highly reproducible, and within the recommended range of moisture content in typical pharmaceuticals and powdered dried food products. The SURE project provided hands-on experience for the URM students on the use of KFT instrument. In addition, the students were able to understand better the application of the concepts of electrochemical oxidation/reduction reactions learned in the Instrumental Analysis course through their utilization for the determination of moisture content in OTC-pharmaceuticals and food products. This SURE project also provided the opportunity for the URM students to resolve the most commonly encountered laboratory challenges and KFT instrument troubleshooting during the laboratory chemical analysis. Furthermore, the SURE project provided the opportunity for the UMR students to learn about scientific report writing, use of library resources and to present the findings of the KFT analysis locally and at regional and national conferences.

Key Words: Laboratories and Demonstrations; organic chemistry; summer-undergraduate-research-program; over-the-counter-pharmaceuticals analysis; powdered foods; moisture-determination; Karl-Fischer titration;   Inquiry-based-study; Electrochemistry

(*) Corresponding author. (E-mail:

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