The document discusses electron microscopy, an advanced imaging technique that uses a beam of electrons to magnify small objects. It explains the principles, procedures, types (Scanning Electron Microscope and Transmission Electron Microscope), applications across various fields, advantages like high resolution, and challenges such as sample preparation and cost. The document serves as an overview of the methods and benefits of electron microscopy in scientific research.

1. Electron Microscope
In the world of microscopes, the electron microscope is an advanced part of it.
NITHISH KRISHNA R
19.03.2024

2. Introduction to Electron Microscopy:
Definition of Electron Microscopy:
An electron microscope (EM) is an instrument (microscope)
that uses a beam of electrons to create an enlarged (magnification)
image of a small object (microorganism).

3. Principles of Electron Microscopy:
A high voltage current is applied which results in the
excitation of the electrons in the form of a continuous
stream that is used as a beam of light.
 Comparison with Light Microscopy light is used
 In electron microscope, Electron Beam Generation
 Interaction of Electrons with Specimens
 Imaging and Magnification

4. Procedure for Using:
 Primary fixation with aldehydes (proteins).
 Secondary fixation with osmium tetroxide (lipids).
 Dehydration series with solvent (ethanol or acetone) and Drying.
 Mounting on a stub and Sputter coating with a conductive material.
 Washing and postfixation.
 Dehydration and Infiltration with resin.
 Curing the resin in a mold for 48 hours.
 Sputtering the sample with a thin layer of metal to increase contrast.
 Placing it in an electron microscope sample chamber.
 Creating pressure in the electron microscope sample chamber.
 Passing the electron beam and visualizing the in the monitor.

5. Types of Electron Microscopes:
There are many types of electron microscopes the
main two types of electron microscopes are :
 Scanning Electron Microscope (SEM)
 Transmission Electron Microscope (TEM)

6. SCANNING ELECTRON MICROSCOPE:(SEM)
Scanning Electron Microscopy (SEM) is a technique for imaging
the surface image or 3D structure of solids (microorganisms) using a
beam of high-energy electrons just to scan without penetrating through
the solid (microorganisms).

7. TRANSMISSION ELECTRON MICROSCOPE: (TEM)
Transmission Electron Microscopy (TEM) is a technique for
imaging the internal structure of solids (microorganisms) using a beam of
high-energy electrons transmitted through the solid (microorganisms).
This arrangement can be compared to the basic optical microscope with
transmission illumination (sometimes called a biological microscope).

8. Applications of Electron Microscopy:
 Biological Sciences
Cell Structure
Molecular Biology
Pathology
 Materials Science
Nanomaterials
Crystallography
Surface Analysis
 Industrial Applications
Quality Control
Failure Analysis
Semiconductor Industry

9. Advantages of Electron Microscopy:
 High Resolution
 Depth of Field
 Magnification Range (up to 10000000x)
 Imaging Capabilities (e.g., Elemental Analysis, Surface Topography)

10. Limitations and Challenges:
 Sample Preparation Issues
 High Vacuum Requirements
 Complex Operation and Maintenance
 Cost