Nanoscale ion-pair reversed-phase HPLC-MS for sensitive metabolome analysis

Area of Science:

• Metabolomics
• Analytical Chemistry
• Biochemistry

Background:

• Metabolite analysis is crucial for understanding cellular processes.
• Existing methods for metabolite separation and identification can be limited in sensitivity and scope.
• Development of advanced analytical techniques is needed for comprehensive metabolome profiling.

Purpose of the Study:

• To introduce and validate a novel method for the separation and identification of metabolites in cell extracts.
• To establish sensitive detection limits for a wide range of metabolites.
• To demonstrate the method's utility in analyzing complex biological samples, such as bacterial cell extracts.

Main Methods:

• Nanoscale ion-pair reversed-phase high-performance liquid chromatography (nano-IP-RP-HPLC) coupled with nanoelectrospray ionization high-resolution mass spectrometry (nano-ESI-HRMS).
• Utilized a C18 column with tributylamine (TBA) as the ion-pairing reagent and methanol as the eluent at a basic pH (9.4).
• Employed a (12)C/(13)C labeling strategy for enhanced metabolite identification in complex matrices.

Main Results:

• Achieved upper attomole to low femtomole limits of detection for key metabolites including nucleotides, phosphorylated sugars, organic acids, and coenzyme A thioesters.
• Successfully identified 20 ± 4 metabolites from 1.5 ng of Methylobacterium extorquens AM1 biomass.
• Identified 157 ± 5 metabolites from 150 ng of biomass, covering a broad spectrum of metabolite classes.

Conclusions:

• The developed nano-IP-RP-HPLC-nano-ESI-HRMS method provides a sensitive and robust platform for comprehensive metabolome analysis.
• The method is effective for identifying a large number of metabolites from small amounts of biological material.
• This technique significantly advances the capability for detailed metabolic profiling in various biological systems.