Focused ion beam fabrication of solidified ferritin into nanoscale volumes for compositional analysis using atom probe tomography
Summary The purpose of this investigation was to conduct atom probe tomography (APT) analyses on ferritin specimens prepared with focused ion beam (FIB) to assess whether this approach can be used to effectively characterize biomaterials. Soft matter is particularly sensitive to ion beam exposure wh...
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Published in | Journal of microscopy (Oxford) Vol. 247; no. 3; pp. 288 - 299 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Oxford, UK
Blackwell Publishing Ltd
01.09.2012
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Subjects | |
Online Access | Get full text |
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Summary: | Summary
The purpose of this investigation was to conduct atom probe tomography (APT) analyses on ferritin specimens prepared with focused ion beam (FIB) to assess whether this approach can be used to effectively characterize biomaterials. Soft matter is particularly sensitive to ion beam exposure which can induce physical and chemical changes. We employ protective metal films and low‐energy ion fluence to mitigate potential problems that may be introduced by FIB. This study had two major objectives: (1) to qualitatively assess the viability of the specimens when subjected to the unique physical conditions of APT analysis, namely ultrahigh vacuum, high electric field, and thermal pulsing using a laser and (2) to quantitatively assess the data from such specimens under various experimental parameters and compare the results with appropriate control specimens. For the first objective, a range of experimental parameters were determined that met the basic criteria necessary to validate that ferritin‐based specimens prepared with FIB can retain structural integrity during APT analysis. Initial field evaporation time‐of‐flight mass spectrometry (TOF‐MS) data show that the specimens fabricated with FIB are capable of emitting ions under various laser pulsing conditions with a high electric field applied. For the second objective, the experimental parameter space was narrowed to a range that yielded data quality sufficient to produce meaningful comparison between the ferritin‐based specimens and the salt‐only controls. |
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Bibliography: | ark:/67375/WNG-TT46NX0R-7 istex:86454EA99FF87FB8CE50F4B36A24008C298B0561 ArticleID:JMI3644 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 ObjectType-Article-2 ObjectType-Feature-1 |
ISSN: | 0022-2720 1365-2818 |
DOI: | 10.1111/j.1365-2818.2012.03644.x |