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Hippuric acid test using 13C-labelling and NMR spectroscopy
1School of Pharmacy, Tokyo University of Pharmacy and Life Science, Hachioji, Japan. akira@ps.toyaku.ac.jp
Clinical Chemistry and Laboratory Medicine
|May 15, 2001
Summary
A novel nuclear magnetic resonance (NMR) method using 13C-labelled benzoic acid can assess liver reserve by quantifying excreted hippuric acid. This simple, chromatography-free approach offers new insights into hepatic energy metabolism.
Area of Science:
- Biochemistry
- Medical Diagnostics
- Nuclear Magnetic Resonance Spectroscopy
Background:
- The hippuric acid test is a traditional method for evaluating liver function.
- Conventional methods for hippuric acid analysis are often time-consuming and require chromatographic separation.
- Assessing liver reserve is crucial for patient management and treatment planning.
Purpose of the Study:
- To describe and validate a novel 13C-labelling and nuclear magnetic resonance (NMR) approach for the hippuric acid test.
- To investigate the feasibility of using NMR spectroscopy for direct analysis of urinary hippuric acid.
- To establish whether this method can serve as a reliable index of liver reserve.
Main Methods:
- Administration of 13C-labelled benzoic acid to healthy subjects.
- Direct analysis of urine samples using 13C nuclear magnetic resonance (NMR) spectroscopy.
- Quantitation of excreted 13C-labelled hippuric acid without chromatographic separation.
Main Results:
- The NMR approach successfully quantified 13C-labelled hippuric acid in urine samples.
- The amount of excreted labelled hippuric acid correlated with liver reserve.
- The method proved simple, convenient, and free from interference by endogenous hippuric acid.
Conclusions:
- The described 13C-NMR method is a feasible and advantageous alternative for the hippuric acid test.
- This approach provides a simple, direct, and sensitive index for evaluating liver reserve.
- The method offers potential for new insights into hepatic energy metabolism and liver function assessment.
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