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bioRxiv · 10.64898/2026.04.02.716008

DM: a simple solution to suppress air-water interface interactions in cryo-EM

Rafiq, M.·Schaefer, J.-H.·Rahmani, H.·You, S.·Bollong, M. J.·Grotjahn, D.·Wiseman, L.·Lander, G. C.
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Abstract

The air-water interface (AWI) remains the primary barrier to routine high-resolution cryo-EM structure determination, driving protein adsorption, structural denaturation, and restricted particle orientations during vitrification. Here, we describe a simple and broadly applicable strategy to mitigate these effects using the mild non-ionic detergent n-decyl-{beta}-D-maltopyranoside (DM). Addition of DM at low millimolar concentrations immediately prior to vitrification consistently suppresses AWI-driven artifacts, resulting in improved angular sampling, reduced structural damage, and enhanced reconstruction quality across diverse macromolecular systems. Using this approach, we obtained a high-resolution reconstruction of the 65 kDa Nucleophosmin 1 pentamer, a target previously limited by severe preferred orientation issues. We further show that DM promotes isotropic particle distributions for high-resolution reconstruction of hemagglutinin, transthyretin, as well as suppressing denaturation of aldolase while stabilizing its C-terminus. Our results indicate that DM effectively passivates deleterious air-water interface interactions without compromising particle integrity. These results establish DM as an effective additive for improving the robustness of single-particle cryo-EM sample preparation. O_FIG O_LINKSMALLFIG WIDTH=174 HEIGHT=200 SRC="FIGDIR/small/716008v1_ufig1.gif" ALT="Figure 1"> View larger version (56K): org.highwire.dtl.DTLVardef@108a6edorg.highwire.dtl.DTLVardef@10728b4org.highwire.dtl.DTLVardef@1014b2eorg.highwire.dtl.DTLVardef@1eed745_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Rafiq, M., Schaefer, J.-H., Rahmani, H., You, S., Bollong, M. J., Grotjahn, D., Wiseman, L., Lander, G. C.. 2026-04-05. DM: a simple solution to suppress air-water interface interactions in cryo-EM. https://doi.org/10.64898/2026.04.02.716008

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