From 1H NMR Spectra to pH and vice versa

ANYL 93

Mika SJ. Tiainen, Mika.Tiainen@uku.fi, Tuulia Tynkkynen, Pasi PK. Soininen, pasi.soininen@uku.fi, and Reino Laatikainen. Department of Chemistry, University of Kuopio, P.O.Box 1627, Kuopio, 70211, Finland
The pH measurement of small volume NMR samples (< 100 µl), typical for biological applications, is difficult. In this work, we developed a set of reference compounds based on 1H NMR chemical shifts. The compounds must fulfill several conditions: they must be chemically inert; give a simple spectrum, preferably at very low or high field; and the spectrum should be insensitive to ionic strength. In addition to pH measurements, this can be applied vice versa: by measuring reference chemical shifts in a mixture, positions of spectral signals of other compounds of the mixture can be predicted from the model ("adaptive spectral library") where the positions are presented vs. pH, or the reference shifts. In this poster, an application of the approach to quantitative NMR analysis of amino acid mixtures is presented.
 

General Papers
7:00 PM-9:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster

Division of Analytical Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006