Oxygen plasma focused ion beam scanning electron microscopy for biological samples

Gorelick, S.; Korneev, D.; Handley, A.; Gervinskas, G.; Oorschot, V.; Kaluza, O. L.; Law, R. H.; O'Bryan, M.; Pocock, R.; Whisstock, J. C.; de Marco, A.

doi:10.1101/457820

bioRxiv · 10.1101/457820

Oxygen plasma focused ion beam scanning electron microscopy for biological samples

Gorelick, S.·Korneev, D.·Handley, A.·Gervinskas, G.·Oorschot, V.·Kaluza, O. L.·Law, R. H.·O'Bryan, M.·Pocock, R.·Whisstock, J. C.·de Marco, A.

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Abstract

Over the past decade, gallium Focused Ion Beam-Scanning Electron Microscopy (FIB-SEM) has been established as a key technology for cellular tomography. The utility of this approach, however, is severely limited both by throughput and the limited selection of compatible sample preparation protocols. Here, we address these limitations and present oxygen plasma FIB (O-PFIB) as a new and versatile tool for cellular FIB-SEM tomography. Oxygen displays superior resin compatibility to other ion beams and produces curtain-free surfaces with minimal polishing. Our novel approach permits more flexible sample preparation and 30% faster data collection when compared to using gallium ion sources. We demonstrate this alternative FIB is applicable to a variety of embedding procedures and biological samples including brain tissue and whole organisms. Finally, we demonstrate the use of O-PFIB to produce targeted FIB-SEM tomograms through fiducial free en-block correlative light and electron microscopy.

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Gorelick, S., Korneev, D., Handley, A., Gervinskas, G., Oorschot, V., Kaluza, O. L., Law, R. H., O'Bryan, M., Pocock, R., Whisstock, J. C., de Marco, A.. 2018-10-31. Oxygen plasma focused ion beam scanning electron microscopy for biological samples. https://doi.org/10.1101/457820

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