Soft x-ray spectromicroscopy of environmental and biological samples

Sedlmair, Julia

doi:10.17875/gup2011-80

Cited by 7 publications

(4 citation statements)

References 181 publications

(322 reference statements)

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“…4. In general, the biological components of MTB cells can be studied without significant radiation damage, albeit at lower spatial resolution, using conventional STXM, as shown in many studies of biological and environmental samples (22,(52)(53)(54)(55). With present soft X-ray ptychography capabilities, the doses required are such that the C 1s, N 1s, and O 1s spectra, which are those spectra most sensitive to the biological components, cannot be measured without damage.…”

Section: Discussionmentioning

confidence: 99%

Measuring spectroscopy and magnetism of extracted and intracellular magnetosomes using soft X-ray ptychography

Zhu

Hitchcock

Bazylinski

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

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Characterizing the chemistry and magnetism of magnetotactic bacteria (MTB) is an important aspect of understanding the biomineralization mechanism and function of the chains of magnetosomes (Fe 3 O 4 nanoparticles) found in such species. Images and X-ray absorption spectra (XAS) of magnetosomes extracted from, and magnetosomes in, whole Magnetovibrio blakemorei strain MV-1 cells have been recorded using soft X-ray ptychography at the Fe 2p edge. A spatial resolution of 7 nm is demonstrated. Precursor-like and immature magnetosome phases in a whole MV-1 cell were visualized, and their Fe 2p spectra were measured. Based on these results, a model for the pathway of magnetosome biomineralization for MV-1 is proposed. Fe 2p X-ray magnetic circular dichroism (XMCD) spectra have been derived from ptychography image sequences recorded using left and right circular polarization. The shape of the XAS and XMCD signals in the ptychographic absorption spectra of both sample types is identical to the shape and signals measured with conventional bright-field scanning transmission X-ray microscope. A weaker and inverted XMCD signal was observed in the ptychographic phase spectra of the extracted magnetosomes. The XMCD ptychographic phase spectrum of the intracellular magnetosomes differed from the ptychographic phase spectrum of the extracted magnetosomes. These results demonstrate that spectro-ptychography offers a superior means of characterizing the chemical and magnetic properties of MTB at the individual magnetosome level.ptychography | magnetotactic bacteria | biomineralization | STXM |

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Section: Discussionmentioning

confidence: 99%

Measuring spectroscopy and magnetism of extracted and intracellular magnetosomes using soft X-ray ptychography

Zhu

Hitchcock

Bazylinski

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

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“…aromatic, phenolic, and carbonyl functional groups. NEXAFS spectra acquired at various absorption edges with the compact spectrometer at LLG: a C K-edge spectra of polyimide, humic acid, fulvic acid and a luvisol bulksoil [19], b Cl L-edge spectrum of NaCl [20] indicating EXAFS oscillations, in comparison with corresponding synchrotron results [21], c overview spectrum of PCMO [22], d O K-edge and Mn L-edge spectra of various Mn compounds [23] and e O K-edge and Fe L-edge spectra of hematite samples of different thickness Furthermore, NEXAFS studies were conducted at the absorption edges of Si, S, Cl (see Fig. 21.7b, [20]), Ca [24], O [22,23], and, for the first time with a laboratoryscale setup, at the L-edges of Mn, Fe and Cu [22,23,25] at photon energies >500 eV (Fig.…”

Section: X-ray Absorption Spectroscopymentioning

confidence: 99%

“…Fig.21 7. NEXAFS spectra acquired at various absorption edges with the compact spectrometer at LLG: a C K-edge spectra of polyimide, humic acid, fulvic acid and a luvisol bulksoil[19], b Cl L-edge spectrum of NaCl[20] indicating EXAFS oscillations, in comparison with corresponding synchrotron results[21], c overview spectrum of PCMO[22], d O K-edge and Mn L-edge spectra of various Mn compounds[23] and e O K-edge and Fe L-edge spectra of hematite samples of different thickness…”

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confidence: 99%

Laboratory-Scale Soft X-ray Source for Microscopy and Absorption Spectroscopy

Müller

Mann

2020

Topics in Applied Physics

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Soft X-ray microscopy and absorption spectroscopy are extremely useful tools for high-resolution imaging and chemical analysis of samples in various scientific fields. However, due to the required high photon flux of soft X-ray radiation, up to now, both methods are almost exclusively performed at synchrotron sources. Thus, great efforts have been made to develop table-top sources emitting in the soft X-ray spectral range ($$\lambda =$$ λ = 1–5 nm). Here, the development of a laser-produced plasma source from a pulsed gas jet is presented, enabling the construction of an almost debris-free, compact and long-term stable X-ray source. Based on this source a compact soft X-ray microscope (spatial resolution 50 nm) operating at a wavelength of $$\lambda = 2.88$$ λ = 2.88 nm was built and applied for imaging of various test and biological objects. In addition, a laboratory-scale NEXAFS spectrometer has been established, allowing for reliable analysis of different absorption edges at photon energies between 250 and 1250 eV.

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“…Due to the manifold of possible X-ray microscopy techniques, a careful combination of dierent imaging modalities is of utmost importance and exemplifying work is needed when new techniques arise. Some applications of soft X-ray microscopy modalities can be found in the works of [100,188,271,300,301] and the reviews [50,161,167,219,256,290] and references therein. Recent applications with a geobiological context are also given in the works of [22,131,204,218] to name a few examples.…”

Section: Scanning Hard X-ray Microscopy Imaging Modalities For Geobio...mentioning

confidence: 99%

Coherent X-Ray Diffractive Imaging on the Single-Cell-Level of Microbial Samples:

Niklas¹

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Among eukarya and archaea, bacteria including the well-known Escherichia coli form one prominent domain of single-celled, microbial life. On a comparably large scale, the constitution of bacterial cells is fairly simple. There is only the cytoplasma containing e.g. proteins, lipids, nucleic acids and ribosomes which is enclosed and protected from the outside by the cytoplasmic membrane and the cell wall. If one denes 'local ordering' as a repetitive structure that can be described by signicant Fourier components one nds the organisation of the bacterial cell to be comparably unordered on a spatial scale above about 10 nm. Below this scale Due to coherent interference, X-ray diraction experiments can be highly sensitive to structures expressing local ordering on such small length scales. However, the local ordering of all these cellular structures is not always as perfect as the structure of single crystals. One thus expects probing such structures with X-rays to be challenging from a point of view of the level of ordering and due to the fact that they consist of soft, weakly scattering biological matter that is prone to radiation damage. In addition, the ordering is restricted to small regions of the bacterial sample implying that the scattering contributions can be expected to be highly position dependent when illuminated with a suciently small X-ray beam. On larger samples such as wood, bone, alloys and muscles, scanning small angle X-ray scattering (SAXS) experiments have already been successfully carried out using micron-sized beams [29,87,88,106,157,171,224,248,318]. Due to the technological of ptychographic imaging experiments with an emphasis on exploiting the full ux capabilities of the GINIX. The nal branch aimed at exploring new bacterial sample systems extending the landscape of sample systems that were initially available in the laboratory of T. Salditt.'Scanning Hard X-ray Microscopy Imaging Modalities for Geobiological Samples' is an a application of the combination of X-ray dierential phase contrast and X-ray uorescence on the geobiological sample of primary aragonitic elements of the demo-sponge Astrosclera willeyana and a quantitative phase contrast mapping on a consortium of sulfur-oxidizing bacteria with ptychography.'STCS in High-Resolution X-Ray Ptychography Using KB Focusing' is dedicated to exploit the maximum available coherent light available at the GINIX for high-resolution, quantitative ptychographic imaging. The limitations set by count-rates of modern photon counting detectors were eectively overcome by using a Semi-Transparent Central Stop (STCS) which attenuates the primary X-ray beam in front of the detector to feasible levels. 'An STCS Application in High-Resolution X-Ray Ptychography' follows the line of the preceding section by presenting a high-ux ptychographic imaging experiment at the GINIX on solar cell nanowires as representatives of nonresolution-chart-type samples. 'Quantitative Waveguide-Based Imaging of B. thuringiensis and B. subtilis' exploits quantitative high-resolu...

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Soft x-ray spectromicroscopy of environmental and biological samples

Cited by 7 publications

References 181 publications

Measuring spectroscopy and magnetism of extracted and intracellular magnetosomes using soft X-ray ptychography

Measuring spectroscopy and magnetism of extracted and intracellular magnetosomes using soft X-ray ptychography

Laboratory-Scale Soft X-ray Source for Microscopy and Absorption Spectroscopy

Coherent X-Ray Diffractive Imaging on the Single-Cell-Level of Microbial Samples:

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