isolated proteins, both ambient temperature work and cryo screening work
monolayers
bacteria and viruses
particulate size and distribution in non-biological samples plus diffraction
Experienced staff are here to provide support in all areas of TEM. Training is available for Newcastle University researchers which will reduce costs in the long term.
Ultrathin sections are stained with heavy metal salts (uranyl acetate and lead citrate) in order to increase the density of the samples and provide contrast to the image.
This technique is used for most resin-embedded biological samples.
A concentrated suspension of particles is deposited onto a coated grid. A drop of heavy metal salt is applied to the grid and surrounds the sample. The electron beam will pass through the sample easier than the surrounding stain and in the resulting image the sample particles will appear light and the surrounding area dark.
This technique is used for the visualisation of bacteria flagellae, viruses, and isolated proteins.
Research expertise in the area of protein analysis is provided by Prof. Robin Harris, who works closely with teams led by Prof. Rick Lewis, and Prof. Jeremy Lakey.
Enzyme histochemistry using 3,3-diaminobenzidine (DAB) can be visualised at the ultrastructural level as the DAB reacts with osmium tetroxide to give an electron dense deposit.
The procedure is carried out on tissue sections prior to embedding in resin.