Proton, Deuterium, and Oxygen-17 Nuclear Magnetic Resonance Relaxation Studies of Lactose and Sucrose-Water Systems

Hsi Mei Lai, Shelly J Schmidt

Research output: Contribution to journalArticlepeer-review

Abstract

Comparison of the 1H, 2H, and 17O nuclear magnetic resonance (NMR) transverse relaxation rate (R2) of water associated with lactose- and sucrose-H2O (or D2O) systems was studied as a function of pH and sugar concentration. The 3.6 g of lactose/mol of H2O 1H NMR R2 measurements varied greatly as a function of pH, reaching a maximum near neutral pH, whereas the 2H NMR R2 measurements varied only slightly as a function of pH. The difference in the contribution of chemical exchange to the transverse relaxation experienced by the 1H and 2H nuclei was proposed to explain the observed variation between the two nuclei. For all three nuclei, ΔR2 increased with increasing sugar concentration. However, the magnitude of these increases, as well as the trends in ΔR2 vs concentration for each nucleus and sugar type, varied widely. Comparison of the 1H, 2H, and 1H-decoupled 17O NMR R2 values, on a normalized basis (ΔR2/R2F), suggested that only the 17O monitors directly the water mobility in the two sugar-H2O (or D2O) systems studied here.

Original languageEnglish (US)
Pages (from-to)1921-1926
Number of pages6
JournalJournal of Agricultural and Food Chemistry
Volume39
Issue number11
DOIs
StatePublished - Nov 1 1991

ASJC Scopus subject areas

  • General Chemistry
  • General Agricultural and Biological Sciences

Fingerprint

Dive into the research topics of 'Proton, Deuterium, and Oxygen-17 Nuclear Magnetic Resonance Relaxation Studies of Lactose and Sucrose-Water Systems'. Together they form a unique fingerprint.

Cite this