Cooperative hydration of pyruvic acid in ice

Marcelo I. Guzmán, Lea Hildebrandt, Agustín J. Colussi, Michael R. Hoffmann

Research output: Contribution to journalArticlepeer-review

36 Scopus citations


About 3.5 ± 0.3 water molecules are still involved in the exothermic hydration of 2-oxopropanoic acid (PA) into its monohydrate (2,2- dihydroxypropanoic acid, PAH) in ice at 230 K. This is borne out by thermodynamic analysis of the fact that QH(T) = [PAH]/[PA] becomes temperature independent below ∼250 K (in chemically and thermally equilibrated frozen 0.1 ≤ [PA]//M ≤ 4.6 solutions in D2O), which requires that the enthalpy of PA hydration (ΔHH ∼ -22 kJ mol-1) be balanced by a multiple of the enthalpy of ice melting (ΔHM = 6.3 kJ mol-1). Considering that: (1) thermograms of frozen PA solutions display a single endotherm, at the onset of ice melting, (2) the sum of the integral intensities of the 1δ PAH and 1δPA methyl proton NMR resonances is nearly constant while, (3) line widths increase exponentially with decreasing temperature before diverging below ∼230 K, we infer that PA in ice remains cooperatively hydrated within interstitial microfluids until they vitrify.

Original languageEnglish
Pages (from-to)10621-10624
Number of pages4
JournalJournal of the American Chemical Society
Issue number32
StatePublished - Aug 16 2006

ASJC Scopus subject areas

  • Catalysis
  • General Chemistry
  • Biochemistry
  • Colloid and Surface Chemistry


Dive into the research topics of 'Cooperative hydration of pyruvic acid in ice'. Together they form a unique fingerprint.

Cite this