Revisiting sodium phosphotungstate and ammonium molybdate as nonradioactive negative-staining agents for single-particle analysis

2024/11/26 by Monika Gunkel, Arthur Macha, Elmar Behrmann · 1 voice
Materials Science · Physics and Astronomy · Chemistry · #Electron and X-Ray Spectroscopy Techniques #X-ray Spectroscopy and Fluorescence Analysis #Radioactive element chemistry and processing

paper · pdf · doi:10.1107/s2053230x24011294

Abstract

This study reports the successful replacement of uranyl-based stains by either sodium phosphotungstate or ammonium molybdate in 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 β-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 nonradioactive, 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, directly after purification, accessible to a broader range of scientists.

Discussions

• Safer, nonradioactive staining alternatives for electron microscopy are introduced, simplifying sample preparation, reducing costs and making structural biology more accessible to researchers globally [bsky, 16 points, 0 comments]

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