DMSO as an internal standard for the analysis of solvent mixtures by qNMR

CHED 291

Peter T. Bell, Alyssa D. Adkins, O'dell Hicks, bell@tarleton.edu, and Linda D. Schultz, schultz@tarleton.edu. Department of Chemistry, Geosciences, & Environmental Science, Tarleton State University, Box T-0540, Stephenville, TX 76402
Dimethyl sulfoxide, DMSO, is an excellent internal standard for the analysis of many solvent mixtures by quantitative nuclear magnetic resonance, qNMR. DMSO is relatively nontoxic, has a lower volatility than many other common solvents, is sufficiently water soluble to be used with D2O as the NMR solvent, and exhibits a single peak in its 1-H spectrum. Solvent mixtures analyzed in this study include acetone, ethyl alcohol, methyl alcohol, tetrahydrofuran and N,N-dimethylformamide. The technique is simple, rapid, and gives good results at the per cent level.