iTome Volumetric Serial Sectioning Apparatus for TEM

Peale, D. R.; Hess, H.; Lee, P. R.; Cardona, A.; Bock, D.; Schneider-Mizell, C. M.; Fetter, R. D.; Lee, W.-P.; Robinson, C. G.; Iyer, N.; Managan, C.

doi:10.1101/2024.07.02.601671

bioRxiv · 10.1101/2024.07.02.601671

iTome Volumetric Serial Sectioning Apparatus for TEM

Peale, D. R.·Hess, H.·Lee, P. R.·Cardona, A.·Bock, D.·Schneider-Mizell, C. M.·Fetter, R. D.·Lee, W.-P.·Robinson, C. G.·Iyer, N.·Managan, C.

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Abstract

An automated ultra-microtome capable of sectioning thousands of ultrathin sections onto standard TEM slot grids was developed and used to section: a complete Drosophila melanogaster first-instar larva, three sections per grid, into 4,866 34-nm-thick sections with a cutting and pickup success rate of 99.74%; 30 microns of mouse cortex measuring roughly 400 um x 2000 um at 40 nm per slice; and a full adult Drosophila brain and ventral nerve column into 9,300 sections with a pickup success rate of 99.95%. The apparatus uses optical interferometers to monitor a reference distance between the cutting knife and multiple sample blocks. Cut sections are picked up from the knife-boat water surface while they are still anchored to the cutting knife. Blocks without embedded tissue are used to displace tissue-containing sections away from the knife edge so that the tissue regions end up in the grid slot instead of on the grid rim.

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Peale, D. R., Hess, H., Lee, P. R., Cardona, A., Bock, D., Schneider-Mizell, C. M., Fetter, R. D., Lee, W.-P., Robinson, C. G., Iyer, N., Managan, C.. 2024-07-04. iTome Volumetric Serial Sectioning Apparatus for TEM. https://doi.org/10.1101/2024.07.02.601671

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