Cryo-OrbiSIMS for 3D Molecular Imaging of a Bacterial Biofilm in Its Native State.
Anal Chem
; 92(13): 9008-9015, 2020 07 07.
Article
em En
| MEDLINE
| ID: mdl-32460495
ABSTRACT
Secondary ion mass spectrometry (SIMS) is gaining popularity for molecular imaging in the life sciences because it is label-free and allows imaging in two and three dimensions. The recent introduction of the OrbiSIMS has significantly improved the utility for biological imaging through combining subcellular spatial resolution with high-performance Orbitrap mass spectrometry. SIMS instruments operate in high-vacuum, and samples are typically analyzed in a freeze-dried state. Consequently, the molecular and structural information may not be well-preserved. We report a method for molecular imaging of biological materials, preserved in a native state, by using an OrbiSIMS instrument equipped with cryogenic sample handling and a high-pressure freezing protocol compatible with mass spectrometry. The performance is demonstrated by imaging a challenging sample (>90% water) of a mature Pseudomonas aeruginosa biofilm in its native state. The 3D distribution of quorum sensing signaling molecules, nucleobases, and bacterial membrane molecules is revealed with high spatial-resolution and high mass-resolution. We discover that analysis in the frozen-hydrated state yields a 10â¯000-fold increase in signal intensity for polar molecules such as amino acids, which has important implications for SIMS imaging of metabolites and pharmaceuticals.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pseudomonas aeruginosa
/
Espectrometria de Massa de Íon Secundário
/
Biofilmes
Idioma:
En
Revista:
Anal Chem
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Reino Unido