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Determination of standard sample purity using the high-precision 1H-NMR process.
1Federal Criminal Police Office, Forensic Science Institute, Wiesbaden, Germany. torsten.schoenberger@bka.bund.de
Analytical and Bioanalytical Chemistry
|February 14, 2012
Summary
High-precision quantification using proton nuclear magnetic resonance ((1)H-NMR) accurately determines analytical standard sample purity. This validated method achieves low uncertainty (0.15%) even with small sample sizes.
Area of Science:
- Analytical Chemistry
- Spectroscopy
Background:
- Accurate purity determination is crucial for analytical standards.
- Proton Nuclear Magnetic Resonance ((1)H-NMR) is a powerful spectroscopic technique.
Purpose of the Study:
- To present a high-precision quantification technique using (1)H-NMR for analytical standard purity.
- To optimize sample preparation and NMR parameters for minimal measurement uncertainty.
Main Methods:
- Utilized internal reference samples in (1)H-NMR experiments.
- Optimized sample preparation and NMR parameters.
- Validated accuracy and precision using certified reference materials.
Main Results:
- Achieved high-precision quantification applicable to small sample amounts (down to 2.5 mg).
- Determined a relative combined measurement uncertainty of 0.15%.
- Compared two uncertainty calculation approaches and performed a complete uncertainty budget calculation.
Conclusions:
- The described (1)H-NMR technique offers high precision and accuracy for analytical standard purity assessment.
- The method is robust and reliable, suitable for routine laboratory use.
- The low uncertainty demonstrates the effectiveness of the optimized procedure.
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