<ol><li>Observation of the Hepatitis E Virus Nanoparticles (HEVNPs) using transmission electron microscope (TEM)<ol style="list-style-type:decimal;"><li>Prepare or dilute the HEVNP samples to 0.5 - 2 mg/mL with 10 mM 2-(N-morpholino)ethanesulfonic acid (MES) pH 6.2 for TEM imaging.</li><li>Ionize the carbon-coated grids with 40 mA glow discharge for 30 s to produce a hydrophilic carbon surface. The glow discharge equipment is described in the Table of Materials. NOTE: The hydrophilic carbon surface of the grids can only last for 30 min after glow discharge treatment.</li><li>Hold in tweezers and add 2 &#xB5;L of HEVNP sample to the grid, wait for 15 - 30 s, and blot with filter paper.</li><li>Immediately wash the grid with ddH20 and blot with filter paper.</li><li>Immediately add 2 &#xB5;L of 2% uranyl acetate to the grid, wait 15 s, then blot with filter paper. Dry the sample grids by putting them in an electronic dehumidifying dry cabinet overnight.</li><li>Transfer the grid into a TEM and image at 10-80k magnification. HEVNPs appear in TEM as empty icosahedral proteins that are ~27 nm in diameter, due to the absence of viral RNA.</li></ol></li></ol>

<table class="ck-table-resized"><tbody><tr><td>MES Hydrate</td><td>Sigma-Aldrich Chemical Co</td><td>M8250-250G</td><td>MES</td></tr><tr><td>EMS Glow Discharger</td><td>Electron Microscopy Science</td><td>&#xA0;</td><td>glow discharger</td></tr></tbody></table>

visualization of hepatitis e virus nanoparticles by transmission electron microscopy

Visualization of Hepatitis E Virus Nanoparticles by Transmission Electron Microscopy

Source: <a href="https://app.jove.com/v/57020/surface-functionalization-hepatitis-e-virus-nanoparticles-using">Chen, C. C., et al. Surface Functionalization of Hepatitis E Virus Nanoparticles Using Chemical Conjugation Methods. J. Vis. Exp. (2018)</a>This video demonstrates the preparation and negative staining of hepatitis E virus-like nanoparticles for visualization by transmission electron microscopy. The method highlights the structural integrity of self-assembled capsid-only particles, confirming their uniformity and purity through high-resolution imaging.

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Begin with a carbon-coated transmission electron microscopy or TEM grid placed on a glass slide.Place the slide inside a chamber and apply a glow discharge to make the carbon surface hydrophilic for uniform sample spreading.Remove the slide, hold the grid with tweezers and apply a suspension of Hepatitis E virus (HEV) nanoparticles onto it.These nanoparticles consist of recombinant HEV capsid proteins and lack nucleic acids and accessory viral proteins.Incubate to allow the nanoparticles to adsorb onto the grid surface. Then blot with filter paper to absorb the excess suspension.Wash the grid with deionized water to remove unadsorbed nanoparticles, and blot again.Add uranyl acetate stain and incubate briefly.Uranyl acetate forms an electron-dense background around the nanoparticles, which enhances contrast during TEM imaging.Blot excess stain and place the grid in a dehumidifying chamber to dry.Under TEM, HEV nanoparticles appear as uniform, hollow, icosahedral structures that lack viral nucleic acids.Dilute the HEV nanoparticles samples to between 0.5 and two milligrams per milliliter with 10 millimolar MES, pH 6.2 for a TEM imaging. Ionize the carbon coated grids with 40 milliamp

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4 Views. Begin with a carbon-coated transmission electron microscopy or TEM grid placed on a glass slide.Place the slide inside a chamber and apply a glow discharge to make the carbon surface hydrophilic for uniform sample spreading.Remove the slide, hold the grid with tweezers and apply a suspension of Hepatitis E virus (HEV) nanoparticles onto it.These nanoparticles consist of recombinant HEV capsid proteins and lack nucleic acids and accessory viral proteins.Incubate to ...

Visualization of Hepatitis E Virus Nanoparticles by Transmission Electron Microscopy

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Name	Company	Catalog Number	Comments
MES Hydrate	Sigma-Aldrich Chemical Co	M8250-250G	MES
EMS Glow Discharger	Electron Microscopy Science		glow discharger