NotesFAQContact Us
Search Tips
Peer reviewed Peer reviewed
Direct linkDirect link
ERIC Number: EJ918550
Record Type: Journal
Publication Date: 2010-Aug
Pages: 6
Abstractor: As Provided
Reference Count: 15
ISSN: ISSN-0021-9584
Use of a Spreadsheet to Calculate the Net Charge of Peptides and Proteins as a Function of pH: An Alternative to Using "Canned" Programs to Estimate the Isoelectric Point of These Important Biomolecules
Sims, Paul A.
Journal of Chemical Education, v87 n8 p803-808 Aug 2010
An approach is presented that utilizes a spreadsheet to allow students to explore different means of calculating and visualizing how the charge on peptides and proteins varies as a function of pH. In particular, the concept of isoelectric point is developed to allow students to compare the results of their spreadsheet calculations with those of computer programs that are freely available on the Internet and are designed to calculate the same parameter. Such comparisons allow students to explore the underlying assumptions of their model (and the likely assumptions of the computer programs) and to speculate on ways in which their model might be improved. A discussion of the oligomeric protein hemoglobin is included to show the limitations of the computer programs and to show how the spreadsheet approach can be adapted to treat satisfactorily this important protein. (Contains 2 tables, 2 figures and 1 scheme.)
Division of Chemical Education, Inc and ACS Publications Division of the American Chemical Society. 1155 Sixteenth Street NW, Washington, DC 20036. Tel: 800-227-5558; Tel: 202-872-4600; e-mail:; Web site:
Publication Type: Journal Articles; Reports - Descriptive
Education Level: Higher Education
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A