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bioRxiv · 10.1101/2024.07.19.604222

Revisiting Sodium Phosphotungstate and Ammonium Molybdate as non-radioactive negative staining agents for single particle analysis

Gunkel, M.·Macha, A.·Behrmann, E.
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Abstract

This study reports the successful replacement of uranyl-based stains by either sodium phosphotungstate or ammonium molybdate for negative staining electron microscopy. Using apoferritin as a test specimen, it is demonstrated that in combination with a facile on-grid fixation step both stains yield comparable images to uranyl formate. Subsequently, using {beta}-galactosidase, it is shown that both stains can also successfully be employed for single particle analysis, yielding virtually indistinguishable results from uranyl formate. As both replacement stains are non-radioactive, they are not subjected to the same handling restrictions as uranyl-based stains. Therefore they are not only cheaper to use, but also make decentralized sample grid preparation - thus directly after purification - accessible to a broader range of scientists.

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Gunkel, M., Macha, A., Behrmann, E.. 2024-07-19. Revisiting Sodium Phosphotungstate and Ammonium Molybdate as non-radioactive negative staining agents for single particle analysis. https://doi.org/10.1101/2024.07.19.604222

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