Images from electrons
Electron images from the TEM can be used to achieve different information, for example for morphological, crystallographic or compositional studies.
It is also possible to label molecules with electron dense particles (e.g. nano-sized gold spheres that attach to molecules through immunolabelling techniques) or construct 3-dimensional images of particle, structures or cells through tomography.
Various types of microanalysis are also able to be undertaken using TEM equipped with electron energy loss spectroscopy (EELS) or x-ray energy dispersive spectroscopy (EDS or EDX) systems. These are described in the Microanalysis module.
Click on any of the images on this page to see them at their full resolution.
Example images from the TEM
Bight field electron micrograph of mitochondria from a rat's liver. The tissue was chemically fixed, mounted on a grid, sectioned with a room-temperature ultramicrotome and the section was stained and viewed.
High resolution electron microscope image of lanthanum strontium manganate on left, bismuth ferrite on right.
Dark field image of a zinc oxide crystal.
Selected area diffraction pattern of Nd13CaO7.This video is a sequence of 3 serial electron tomograms of the golgi region of an HIT-T15 cell (a hamster-derived pancreatic beta cell). Such videos are constructed from a series of images taken through a thick tissue section.
Tomograms courtesy of Dr. Brad Marsh
A range of bright field images related to biology [see sample preparation for background on procedures]
Haemocytes from the Akoya peal oyster, Pinctada imbricata. M: mitochondria; N: nucleus; V: vacuole; ER: endoplasmic reticulum. The sample has been chemically fixed.
Detail on sample preparation
The samples have been fixed in 4% paraformaldehyde plus 2% glutaraldehyde in 0.1M Pipes buffer and 0.3M sucrose. Following this chemical fixation, the tissue was post-fixated using OsO4. The tissue was then dehydrated using a graded series of ethanol to 100%. It was then infiltrated with LR White resin. After polymerisation of the resin into solid blocks, thin sections were cut using a room-temperature ultramicrotome. Sections were picked up on a grid, then strained, dried and viewed.
Baby Hampster Kidney (BHK) cells. This tissue was fixed by high pressure freezing followed by freeze substitution.
Detail on sample preparation
This tissue was fixed by high pressure freezing followed by freeze substitution. It was then low temperature embedded in the resin HM20. The block was then sectioned at room-temperature by ultramicrotomy, picked up on a grid, stained, dried and viewed.
The rod-shaped secretion used in the temporary glue of Troglocephalus rhinobatidis marine parasites. These external parasites of stingrays look like small worms. The black dots show sugar chemistry on the surface of the secretions (cross sections and longitidinal sections of rod-secretions are shown).
Detail on sample preparation
Molecules within cells can be labelled using a variety of methods but to see them using electron microscopy the labels must be electron dense or couplled to electron dense material such as silver or gold particles. This tissue has been labelled using a modification of the periodic acid-Schiff (PAS) histochemical method with silver as the visible marker under electron microscope: a periodic acid-thiosemicarbazide-silver proteinate reaction. PAS is used to detect polysaccharides such as glycogen, glycoproteins and glycolipids.
Here, ultrathin sections prepared from chemically fixed tissue were placed on nickel grids, treated with 0.5% periodic acid in water for 20 min, rinsed with water, then reacted with 1% thiosemicarbazide in 10% acetic acid for 30 min. They were then rinsed in a series of water washes. The sections were reacted with 1% silver proteinate in water in darkness for 30 min, rinsed and dried. The labelled sections on grids were then stained with uranyl acetate and lead citrate and viewed.
Baby Hampster Kidney (BHK) cells labeled for GFP-Rab18: immunolabeled with anti-GFP. The labels are the small black dots. GFP=Green Fluorescence Protein.
Detail on sample preparation
This tissue was fixed by high pressure freezing followed by freeze substitution. It was then low temperature embedded in the resin HM20. The block was then sectioned at room-temperature by ultramicrotomy, picked up on a grid, stained, dried and viewed.
Endothelia in mouse muscle, immunolabeled for cavin1 using the Tokuyasu method. The labels are the small black dots.
Detail on sample preparation
The process used followed the steps: chemical fixation; cryoprotection; high pressure freezing; cryo-ultramicrotomy; thawing; mounting on grid; immunolabeling; staining; drying; and viewing.
