The simplest type of preparation is the wet mount, in which the specimen is placed on the slide in a drop of liquid. Once the liquid has been added to the slide, a coverslip is placed on top and the specimen is ready for examination under the microscope.

Electron microscopes are used to investigate the ultrastructure of a wide range of biological and inorganic specimens including microorganisms, cells, large molecules, biopsy samples, metals, and crystals. Industrially, electron microscopes are often used for quality control and failure analysis.

TEM Sample Preparation Steps:

1. Cut an about 10x10mm piece from the studied material (e.g. from a Si wafer) and glue it by a TRANSPARENT THERMOPLASTIC GLUE on a glass plate.
2. Two pieces of Si in size of 1.5×0.5mm are cut with the help of MICROSAW using the 0.15 thick diamond wheel.

But the most advanced and up-to-date technique used for making TEM samples is focused ion beam milling, the abbreviation is FIB.

projection image

Electron microscopy

An electron gun at the top of a TEM emits electrons that travel through the microscope’s vacuum tube. Rather than having a glass lens focusing the light (as in the case of light microscopes), the TEM employs an electromagnetic lens which focuses the electrons into a very fine beam.

Viruses are very small and most of them can be seen only by TEM (transmission electron microscopy).

Early on in my research I discovered that viruses have no color as they are smaller than the wavelength of light. Viruses are so small they can only be seen under an electron microscope (EM) as quite undefined grainy images.

The high resolving power of electron microscopy (EM) permits studies at nanometer scale, providing direct images of viruses for diagnosis and research.

Electron microscopy is widely used in virology because viruses are generally too small for a direct inspection by light microscopy. Analysis of virus morphology is necessary in many circumstances, e.g., for the diagnosis of a virus in particular clinical situations or the analysis of virus entry and assembly.

Plant viruses are extremely minute infectious particles consisting of a protein coat and a core of nucleic acid. They have no means of self-dispersal, but rely on various vectors (including humans) to transmit them from one host to another.

Generally, in order to view and non-differentially count WBCs under a conventional microscope, an objective with the magnification power of at least 10x (0.25NA) is used [16]. For a differential WBC count, an oil-immersion objective with around 100x magnification (1.4NA) is used.

A low WBC count can be serious because it increases your risk of developing a potentially life-threatening infection. Seek prompt medical care if you have a low WBC count and have signs of an infection, such as a fever, swollen lymph nodes, sore throat, or skin lesions.

Vitamin C is thought to increase the production of white blood cells, which are key to fighting infections. Almost all citrus fruits are high in vitamin C. With such a variety to choose from, it’s easy to add a squeeze of this vitamin to any meal. Popular citrus fruits include: grapefruit.