Rapid determination of the original boron isotopic composition from altered basaltic glass by in situ secondary ion mass spectrometry

2020 ◽  
Vol 35 (2) ◽  
pp. 238-245 ◽  
Author(s):  
Miaohong He ◽  
Xiaoping Xia ◽  
Xiaolong Huang ◽  
Jinlong Ma ◽  
Jieqiong Zou ◽  
...  

Rapid determination of the original boron composition from altered basaltic glass by SIMS boron isotopic profile analysis from the core to rim.

2020 ◽  
Author(s):  
Feifei Jia ◽  
Jie Wang ◽  
Yanyan Zhang ◽  
Qun Luo ◽  
Luyu Qi ◽  
...  

<p></p><p><i>In situ</i> visualization of proteins of interest at single cell level is attractive in cell biology, molecular biology and biomedicine, which usually involves photon, electron or X-ray based imaging methods. Herein, we report an optics-free strategy that images a specific protein in single cells by time of flight-secondary ion mass spectrometry (ToF-SIMS) following genetic incorporation of fluorine-containing unnatural amino acids as a chemical tag into the protein via genetic code expansion technique. The method was developed and validated by imaging GFP in E. coli and human HeLa cancer cells, and then utilized to visualize the distribution of chemotaxis protein CheA in E. coli cells and the interaction between high mobility group box 1 protein and cisplatin damaged DNA in HeLa cells. The present work highlights the power of ToF-SIMS imaging combined with genetically encoded chemical tags for <i>in situ </i>visualization of proteins of interest as well as the interactions between proteins and drugs or drug damaged DNA in single cells.</p><p></p>


2021 ◽  
Vol 8 ◽  
Author(s):  
Nordine Bouden ◽  
Johan Villeneuve ◽  
Yves Marrocchi ◽  
Etienne Deloule ◽  
Evelyn Füri ◽  
...  

Secondary ion mass spectrometry (SIMS) is a powerful technique for in situ triple oxygen isotope measurements that has been used for more than 30 years. Since pioneering works performed on small-radius ion microprobes in the mid-80s, tremendous progress has been made in terms of analytical precision, spatial resolution and analysis duration. In this respect, the emergence in the mid-90s of the large-radius ion microprobe equipped with a multi-collector system (MC-SIMS) was a game changer. Further developments achieved on CAMECA MC-SIMS since then (e.g., stability of the electronics, enhanced transmission of secondary ions, automatic centering of the secondary ion beam, enhanced control of the magnetic field, 1012Ω resistor for the Faraday cup amplifiers) allow nowadays to routinely measure oxygen isotopic ratios (18O/16O and 17O/16O) in various matrices with a precision (internal error and reproducibility) better than 0.5‰ (2σ), a spatial resolution smaller than 10 µm and in a few minutes per analysis. This paper focuses on the application of the MC-SIMS technique to the in situ monitoring of mass-independent triple oxygen isotope variations.


Author(s):  
М.Н. Дроздов ◽  
Ю.Н. Дроздов ◽  
А.И. Охапкин ◽  
С.А. Краев ◽  
М.А. Лобаев

AbstractNew possibilities offered by the method of secondary ion mass spectrometry (SIMS) for analysis of the phase composition of carbon-containing materials are considered. Differences are established between the mass spectra of three carbon phases: diamond, diamond-like carbon (DLC), and graphite. A simple algorithm for the quantitative determination of different phases in two-phase systems diamond–graphite and DLC–graphite is proposed that is based on the measurement of relative intensities of secondary cluster ions such as C_8/C_5 and CsC_8/CsC_4. It is shown that nonuniform depth profiles of various carbon phases are formed in diamond structures upon laser cutting and in DLC structures upon thermal annealing.


2007 ◽  
Vol 46 (11) ◽  
pp. 7441-7445 ◽  
Author(s):  
M'hamed Boulakroune ◽  
Ahmed El Oualkadi ◽  
Djamel Benatia ◽  
Tahar Kezai

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