Optimized NMR-Based Metabolomic Protocol for Salivary Analysis in Clinical Practice

Area of Science:

• Biochemistry
• Analytical Chemistry
• Personalized Medicine

Background:

• Saliva is an underutilized biofluid in metabolomics compared to blood and urine.
• Its noninvasive collection and self-sampling suitability make it ideal for clinical applications.
• Saliva offers complementary metabolic data to other biofluids.

Purpose of the Study:

• To identify an optimal protocol for saliva sample collection and preparation.
• To maximize informative metabolomic data from salivary nuclear magnetic resonance (NMR) profiles.
• To establish a reliable method for quantitative salivary metabolomics.

Main Methods:

• Systematic comparison of four adapted preparation protocols.
• Evaluation criteria included metabolite identification, concentration, and intraday repeatability.
• An in-house method combining centrifugation, freeze-drying, and ultrafiltration was optimized.

Main Results:

• The optimized protocol quantified 42 metabolites, providing broad metabolome coverage.
• Analysis of variance confirmed excellent intra- and interday precision (CV < 10%).
• High-quality spectra and strong analytical precision were achieved.

Conclusions:

• The optimized protocol supports reproducible salivary NMR metabolomics.
• Standardized saliva collection and preparation are crucial for its use in diagnostics and disease monitoring.
• Saliva is a promising biofluid for personalized medicine.