NotesFAQContact Us
Search Tips
Peer reviewed Peer reviewed
Direct linkDirect link
ERIC Number: EJ1166991
Record Type: Journal
Publication Date: 2018-Jan
Pages: 4
Abstractor: As Provided
ISSN: ISSN-0021-9584
Experimental Determination of pK[subscript a] Values and Metal Binding for Biomolecular Compounds Using [superscript 31]P NMR Spectroscopy
Swartz, Mason A.; Tubergen, Philip J.; Tatko, Chad D.; Baker, Rachael A.
Journal of Chemical Education, v95 n1 p182-185 Jan 2018
This lab experiment uses [superscript 31]P NMR spectroscopy of biomolecules to determine pK[subscript a] values and the binding energies of metal/biomolecule complexes. Solutions of adenosine nucleotides are prepared, and a series of [superscript 31]P NMR spectra are collected as a function of pH and in the absence and presence of magnesium or calcium ions. The chemical shifts in the spectrum change depending on the protonation state of the phosphate groups and the nucleotide/metal interaction. Because [superscript 31]P NMR spectroscopy is used, the resulting data are clean and readily accessible for student analysis. The use of [superscript 31]P NMR spectroscopy presents a rich opportunity to deepen student engagement with NMR spectroscopy and spectral analysis. Furthermore, the inclusion of biomolecules and metal binding exposes students to important and underrepresented concepts that bridge organic chemistry and biochemistry. Students will learn how to prepare, collect, and analyze non-hydrogen samples using NMR spectroscopy, identify an unknown pK[subscript a], and calculate binding energies for a metal complex. This experiment is suitable for students in a second-year undergraduate organic chemistry course and could also be used in an analytical chemistry, bioorganic chemistry, or an advanced instrumentations laboratory course.
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: National Science Foundation (NSF)
Authoring Institution: N/A
Grant or Contract Numbers: CHE0922973; CHE963433