Practical Protein Chemistry - A. Darbre 1989

X-ray Crystallography and Electron Microscopy
Electron Microscopy
Introduction

Unlike X-Ray Diffraction Analysis, Electron Cell/15.html">Microscopy produces an actual image of the object under study. Electron microscopes are now widely available, and many laboratories can provide expert assistance with both instrument operation and Sample preparation techniques. By 'transilluminating' a specimen in an Electron microscope, one directly obtains images whose proper interpretation yields structural information about the molecules in question. For routine research, a minimal acquaintance with the Physical Principles of the method is usually sufficient. Naturally, however, a deeper understanding of these processes, combined with practical experience, enables researchers to obtain reliable results quickly and with confidence.

The fundamental difference between X-ray diffraction and electron microscopy is that the electron beam scattered by an object can be focused by an electromagnetic lens to produce a magnified image. This makes electron microscopy an exceptionally convenient research tool. Electron microscopes have become so widespread that their design has been refined for higher quality and reliability, as well as ease of use. Today, any biochemist can readily access a high-performance instrument. In the Initial Stages of research, sample screening can be performed by a skilled operator. If desired, the biochemist can then continue the electron microscopic analysis independently, after receiving a brief Introduction from an experienced microscopist.