World Journal of Chemical Education
ISSN (Print): 2375-1665 ISSN (Online): 2375-1657 Website: Editor-in-chief: Prof. V. Jagannadham
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World Journal of Chemical Education. 2014, 2(4), 59-61
DOI: 10.12691/wjce-2-4-3
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The Identification of Amino Acids by Interpretation of Titration Curves: An Undergraduate Experiment for Biochemistry

Cassidy M. Dobson1 and Nathan S. Winter1,

1Department of Chemistry and Biochemistry, St. Cloud State University, St. Cloud, Minnesota, United States

Pub. Date: December 25, 2014

Cite this paper:
Cassidy M. Dobson and Nathan S. Winter. The Identification of Amino Acids by Interpretation of Titration Curves: An Undergraduate Experiment for Biochemistry. World Journal of Chemical Education. 2014; 2(4):59-61. doi: 10.12691/wjce-2-4-3


Undergraduate biochemistry students should have great familiarity with titration curves. These curves allow the prediction of protonation states, charges, and isoelectric points. Here we describe an experiment in which students identify four amino acids based on their titration behavior. Students make solutions of each unknown amino acid and monitor the change in pH upon adding aliquots of a strong base. They identify the amino acids based on the shapes of the curves. They annotate the plots with isoelectric points, pKas, buffering regions and the structures of the amino acids.

titration curve amino acids pH biochemistry pKa isoelectric point

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