Time-Domain-Based Methyl Proton NMR with Absolute Quantitation Ability for Targeted Metabolomics

Area of Science:

• Analytical Chemistry
• Biochemistry
• Spectroscopy

Background:

• High-throughput targeted metabolomics faces challenges with complex NMR spectra and overlapping signals from similar metabolites.
• Traditional frequency-domain NMR suffers from low sensitivity and resolution, impacting quantitation accuracy due to inconsistent phasing and baselining.

Purpose of the Study:

• To establish and demonstrate a time-domain NMR strategy focused on methyl protons for targeted metabolomics.
• To showcase the practicability of this technique for varietal discrimination of toad venoms using bufadienolide analysis.

Main Methods:

• Development of a time-domain NMR strategy specifically targeting methyl protons.
• Application of the technique to targeted metabolomics for bufadienolide analysis in toad venoms.
• Validation of quantitation accuracy using triple-quadrupole mass spectrometry (QqQ-MS).

Main Results:

• Precise identification and quantitation of metabolite signals with a signal-to-noise ratio (SNR) of approximately 10 and a resolution of about 1.0 Hz.
• Demonstrated sensitivity and resolution improvements applicable to targeted metabolomics.
• Confirmed precise and absolute quantitation capabilities, comparable to QqQ-MS.

Conclusions:

• Time-domain NMR focusing on methyl protons offers significant advantages in sensitivity and resolution for targeted metabolomics.
• The technique provides precise and absolute quantitation, extending its applicability.
• This user-friendly method serves as a valuable complementary alternative to traditional frequency-domain NMR for researchers.