RFLP analysis of genomic DNA is facilitated by Southern blot analysis. After electro-phoresis, DNA fragments in the gel are denatured by soaking in an alkali solution. This causes double-stranded fragments to be converted into single-stranded form (no longer base-paired in a double helix). A replica of the electrophoretic pattern of DNA fragments in the gel is made by transferring (blotting) them to a sheet of nitrocellulose or nylon membrane. This is done by placing the membrane on the gel after electro-phoresis and transferring DNA fragments to the membrane by capillary action or electro-transfer. DNA, which is not visible, becomes permanently adsorbed to the membrane, that can then be manipulated easier than gels.
Electron microscope uses a beam of electrons as energy source. Since the beam has an exceptionally short wavelength, it strikes most objects in its path and increases the resolution of the microscope significantly. Thus it has a higher magnification and resolution.
