Orbitrap-based metabolomics workflows: Discover. Innovate. Exceed.

Importance of the topic

Metabolomics has emerged as a critical discipline for understanding cellular processes and disease states by profiling small molecules in complex matrices. High dynamic range and minimal in-source fragmentation are essential to detect both abundant and trace-level metabolites reliably. This requirement drives continual innovation in mass spectrometry.

Objectives and study overview

The presented work describes the design and evaluation of the Orbitrap Excedion Pro hybrid mass spectrometer. Key goals include reducing unintended MS1 fragmentation, extending dynamic range through enhanced dynamic range (eDR) scanning, and improving metabolome coverage in a single injection workflow.

Methodology and Instrumentation

Hardware innovations comprise the Optamax Plus ion source with an electrodynamic ion funnel and optimized RF settings to minimize fragmentation while maximizing transmission of labile species. The eDR approach splits the full MS1 scan into two alternating subscans covering defined m/z windows based on user parameters. Intelligent data acquisition strategies such as Thermo Scientific AcquireX and post-acquisition processing in Compound Discoverer further enhance feature detection and annotation.

Main results and discussion

Soft ion source conditions on the Excedion Pro yielded reduced in-source fragmentation of phenylalanine compared to legacy platforms, resulting in higher signal-to-noise ratios at MS1. Implementation of 16 eDR windows expanded the detectable dynamic range by up to six orders of magnitude, enabling zeptomole-level detection of labeled tyrosine in complex SRM 1950 extracts. Intelligent AcquireX workflows increased feature count by 3.5-fold and annotation rates by 34%. A case study detected a sildenafil analogue III with clear A0 and A1 isotope peaks only when eDR was enabled.

Advantages and practical applications

• Enhanced detection sensitivity for low-abundance metabolites in complex biological samples.
• Reduced saturation of high-abundance ions, improving quantitative linearity.
• Improved confidence in compound identification and relative quantitation at the MS1 level.
• Applicability to biomarker discovery, clinical metabolomics, and QA/QC in pharmaceutical analysis.

Future trends and potential applications

Advances may include tighter integration of AI-driven acquisition methods, further miniaturization for high-throughput and single-cell metabolomics, and enhanced coupling with spectral libraries for automated annotation. Continued hardware and software co-development will drive deeper coverage of low-abundance metabolites.

Conclusion

The Orbitrap Excedion Pro mass spectrometer, with its gentle ion source and eDR scanning mode, represents a significant leap forward for untargeted metabolomics. It delivers broader dynamic range, higher sensitivity, and robust annotation in complex matrices, meeting current and future analytical demands.

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