Characterization of differences between blood sample matrices in untargeted metabolomics

Area of Science:

• Biochemistry
• Analytical Chemistry
• Biotechnology

Background:

• Proteomic and metabolomic technologies are vital for human disease diagnosis.
• Large sample sizes are crucial for statistical power in these analyses.
• Analysis often relies on banked samples with variable documentation of collection and storage.

Purpose of the Study:

• To compare human blood matrices for metabolomic output quality.
• To evaluate the impact of different sample collection and preparation methods on metabolomic profiles.
• To identify and understand matrix effects in blood samples for improved metabolomic analysis.

Main Methods:

• Analysis of human plasma (with various anticoagulants) and serum.
• Comparison of venipuncture and capillary blood collection methods.
• Liquid chromatography-mass spectrometry (LC-MS) for metabolomic profiling.

Main Results:

• Subtle differences observed between plasma preparation methods.
• Serum and plasma differences are primarily peptide/protein-based.
• Lysophosphatidylinositol was more abundant in plasma.
• 23 significant compound differences between capillary and venipuncture samples, some mimicking endogenous metabolites.

Conclusions:

• Blood matrix effects, including collection and preparation, can introduce systematic bias in metabolomic data.
• Understanding these effects is critical for accurate interpretation of metabolomic profiles.
• Careful consideration of sample handling is necessary for reliable disease diagnosis using large-scale omics data.