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Concentration Measurement by Proton NMR Using the ERETIC Method
S Akoka1, L Barantin, M Trierweiler
1Laiem - Upres-A CNRS 6006, Faculté des Sciences, Université de Nantes, 2 rue de la houssinière - BP 92208, 44322 Nantes Cedex 3, France, and Inserm U316 Faculté de Médecine, Université de Tours, 2bis Bd tonnellé, 37032 Tours Cedex, France.
The Electronic REference To access In vivo Concentrations (ERETIC) method offers accurate and precise absolute concentration determination in (1)H NMR. This electronic reference method demonstrates excellent stability and requires only monthly calibration for reliable results.
Area of Science:
- Analytical Chemistry
- Nuclear Magnetic Resonance Spectroscopy
Background:
- Absolute concentration determination is crucial in quantitative analysis.
- Traditional methods often require internal standards added to the sample.
Purpose of the Study:
- To evaluate the accuracy and precision of the ERETIC method for (1)H high-resolution NMR.
- To assess the stability and calibration requirements of the ERETIC method.
Main Methods:
- Utilized the ERETIC method to generate a reference signal for concentration determination.
- Compared ERETIC results with an internal reference standard (trimethylamine hydrochloride).
- Analyzed D(2)O solutions of sodium lactate at varying concentrations.
Main Results:
- ERETIC method showed comparable standard deviations (<1% of the mean) to internal referencing.
- ERETIC exhibited slightly better accuracy than the internal reference method.
- The method demonstrated good stability over 56 hours and monthly intervals (3% standard deviation).
Conclusions:
- The ERETIC method provides accurate and precise absolute concentration measurements in (1)H NMR.
- ERETIC offers advantages such as no sample addition and flexible reference signal placement.
- The method is stable and requires infrequent calibration, making it a reliable quantitative tool.
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