Jul 02, 2026
Post-Staining Protocol for Epon Ultrathin Sections on EM Grids
- Yumei Wu1,2,
- Pietro De Camilli1,2,
- Yumei Wu1,2
- 1Departments of Neuroscience and of Cell Biology, Program in Cellular Neuroscience, Neurodegeneration, and Repair, Howard Hughes Medical Institute, Yale School of Medicine, New Haven, CT 06510.;
- 2Aligning Science Across Parkinson's (ASAP) Collaborative Research Network.
Protocol Citation: Yumei Wu, Pietro De Camilli, Yumei Wu 2026. Post-Staining Protocol for Epon Ultrathin Sections on EM Grids. protocols.io https://dx.doi.org/10.17504/protocols.io.36wgqxx65lk5/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: May 13, 2026
Last Modified: July 02, 2026
Protocol Integer ID: 317018
Keywords: ASAPCRN
Abstract
This protocol describes the post-staining procedure for ultrathin Epon sections on EM grids.
General preparation
Clean the bench with 70% ethanol and place a piece of parafilm on it.
Place one drop of Uranyless on the parafilm. Float the section-side of the EM grid face-down on the drop for 4 minutes.
Wash the grid by floating section-side down on a drop of ultrapure/MiliQ water on clean parafilm for 1 minute. Repeat twice more using two additional drops of fresh water.
Place a piece of parafilm inside a 10 × 2.5 cm cell culture dish containing NaOH pellets (to remove CO2 from the air). Add one drop of lead citrate onto the parafilm.
Remove excess water from the grid by gently dabbing the edge onto filter paper. Float the section-side of the grid face-down on the lead citrate drop for 1–2 minutes, with the dish lid closed.
Repeat step 3 using fresh drops of ultrapure water on clean parafilm.
Gently dab excess water from the grid edge onto filter paper, then store the grid in a grid box.
Allow grids to dry for at least 1 hour before imaging on a Talos L120C TEM microscope.