Cross-Scale Multimodal Imaging for Organic Matter in Extraterrestrial Samples

Area of Science:

• Astrochemistry
• Geochemistry
• Organic Chemistry

Background:

• Analysis of extraterrestrial organic matter is key to understanding prebiotic chemistry and origins.
• Scarcity and complexity of samples present significant analytical challenges.
• Previous methods lacked the resolution and integration needed for comprehensive analysis.

Purpose of the Study:

• To develop and apply a cross-scale multimodal imaging workflow for analyzing extraterrestrial organic matter.
• To establish spatial associations between mineralogy, molecular, and isotopic composition.
• To investigate the occurrence and distribution of organic compounds in the Murchison meteorite.

Main Methods:

• Integrated mass spectrometry imaging (MSI) and vibrational spectroscopy imaging.
• Utilized techniques including DESI-Q-TOF/MS, TOF-SIMS, NanoSIMS, FPA-FTIR, and O-PTIR.
• Improved spatial resolution of DESI to 20 μm for enhanced correlation.

Main Results:

• Observed enrichment of organic matter (CHN, CHO, CHNO compounds, PAHs) in fine-grained rims around chondrules.
• Revealed differences in organic matter composition between Ca-carbonate and phyllosilicates.
• Demonstrated spatial heterogeneity of organic matter within phyllosilicates.

Conclusions:

• The developed workflow enables detailed characterization of organic matter in complex extraterrestrial samples.
• Provides new insights into the distribution and composition of prebiotic materials.
• Establishes a new paradigm for studying organic matter in diverse research fields.