Premium
Effect of polychromatic X‐ray microtomography imaging on the amino acid content of the Murchison CM chondrite
Author(s) -
Friedrich Jon M.,
McLain Hannah L.,
Dworkin Jason P.,
Glavin Daniel P.,
Towbin W. Henry,
Hill Morgan,
Ebel Denton S.
Publication year - 2019
Publication title -
meteoritics and planetary science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.09
H-Index - 100
eISSN - 1945-5100
pISSN - 1086-9379
DOI - 10.1111/maps.13188
Subject(s) - murchison meteorite , carbonaceous chondrite , chondrite , meteorite , chemistry , analytical chemistry (journal) , radiochemistry , astrobiology , chromatography , physics
X‐ray microcomputed tomography (μ CT ) is a useful means of characterizing cosmochemical samples such as meteorites or robotically returned samples. However, there are occasional concerns that the use of μ CT may be detrimental to the organic components of a chondrite. Small organic compounds such as amino acids comprise up to ~10% of the total solvent extractable carbon in CM carbonaceous chondrites. We irradiated three samples of the Murchison CM carbonaceous chondrite under conditions akin to and harsher than those typically used during typical benchtop X‐ray μ CT imaging experiments to determine if detectable changes in the amino acid abundance and distribution relative to a nonexposed Murchison control sample occurred. After subjecting three meteorite samples to ionizing radiation dosages between ~300 Gray (Gy) and 3 kG y with bremstrahlung X‐rays, we analyzed the amino acid content of each sample. Within sampling and analytical errors, we cannot discern differences in the amino acid abundances and amino acid enantiomeric ratios when comparing the control samples (nonexposed Murchison) and the irradiated samples. We conclude that a polychromatic X‐ray μ CT experiment does not alter the abundances of amino acids to a degree greater than how well those abundances are measured with our techniques and therefore any damage to amino acids is minimal.