抄録
Nucleic acid bases in products by proton irradiation of a simulated primitive atmosphere were identified by liquid ionization (LI) mass spectrometry. In order to detect a trace amount of nucleic acid bases, the LI ion source setting was improved in terms of ionization efficiency and ion focusing. The new ion source provided better sensitivity for the analyte (uracil) and lower background of water clusters than the previous one. Addition of a certain amount of a standard compound such as adenine (1 mM) and a kind of matrix (0.2% glycerol) improved the detection limit and the linearity of calibration curves.
When a mixture of carbon monoxide, nitrogen, and water (“a simulated primitive earth atmosphere”) was irradiated with high energy protons, and the nucleic acid bases in the product were analyzed. Uracil, one of the five nucleic acid bases, was identified by LI mass spectrometry using the improved ion source.
