8 research outputs found
The 3D OrbiSIMS—label-free metabolic imaging with subcellular lateral resolution and high mass-resolving power
We report the development of a 3D OrbiSIMS instrument for label-free biomedical imaging. It combines the high spatial resolution of secondary ion mass spectrometry (SIMS; under 200 nm for inorganic species and under 2 μm for biomolecules) with the high mass-resolving power of an Orbitrap (>240,000 at m/z 200). This allows exogenous and endogenous metabolites to be visualized in 3D with subcellular resolution. We imaged the distribution of neurotransmitters—gamma-aminobutyric acid, dopamine and serotonin—with high spectroscopic confidence in the mouse hippocampus. We also putatively annotated and mapped the subcellular localization of 29 sulfoglycosphingolipids and 45 glycerophospholipids, and we confirmed lipid identities with tandem mass spectrometry. We demonstrated single-cell metabolomic profiling using rat alveolar macrophage cells incubated with different concentrations of the drug amiodarone, and we observed that the upregulation of phospholipid species and cholesterol is correlated with the accumulation of amiodarone
The rotational and fine-structure spectrum of FeH, studied by far-infrared laser magnetic resonance
Transitions between the spin-rotational levels of the FeH radical in the υ=0 level of the X4Δ ground state have been detected by the technique of laser magnetic resonance at far-infrared wavelengths. Both pure rotational and fine-structure transitions have been observed; lambda-type doubling is resolved on all the observed transitions. The energy levels of FeH are strongly affected by the breakdown of the Born-Oppenheimer approximation and cannot be modeled accurately by an effective Hamiltonian. The data are therefore fitted to an empirical formula to yield term values and g factors for the various spin-rotational levels involved. Many of the resonances show a doubling that arises from the proton hyperfine structure
Solid state electrochemiluminescence from homogeneous and patterned monolayers of bifunctional spirobifluorene
Electrochemiluminescence (ECL) generated by a monolayer of a
spirobifluorene derivative covalently bound onto an indium tin
oxide (ITO) substrate is reported for the first time. Our approach
allows the efficient preparation homogeneous and patterned
substrates through micromolding in capillaries (MIMIC), and opens
novel scenarios for multicolour ECL applications