Specialised Techniques
8.1 MICROWAVING
Principle: Microwaving is a method used for heating of tissue sections and cellular components with the use of a microwave which provides heat by electromagnetic waves that has a high frequency, with a wavelength if one millimetre to one meter and an intermediate between infrared and shortwave radio wavelengths (Miffin, 2002). This allows fast fixation.
Technique: Electromagnetic waves are commonly used for carrying out energy and are said to be powerful for non-invasive processing of materials (Miffin, 2002). The microwave energy offers relatively large specimens to have the ability of good preservation of cellular structure for light and electron microscopy giving it minimal changes to the cellular biochemistry and antigenicity of the specimen (Neuroski, 1994). Microwave stabilization, fast and ultrafast primary microwave-chemical fixation are common methods used to fix specimens (Neuroski, 1994). Irreproducible fixation results may be from the commercial microwave ovens which have limitations (Neuroski, 1994). Microwaving technique is also used for heat-induced epitope retrieval methods where the use of a domestic microwave is not considered since hot and cold spots are common which lead to uneven antigen retrieval, these may also lead to section dissociation because the retrieval may be longer due to the absence of a pressurized environment (Abcam, n.d.). The use of a scientific microwave is more advisable because most of its bands have board vessels that are pressurized having the ability to keep the temperature at a constant 98 degrees Celcius which avoids the dissociation of tissue sections (Abcam, n.d.) .
SCIENTIFIC MICROWAVE
Images for pictures of scientific microwave available from: www.thermoscientific.com
8.2 ELECTRON MICROSCOPY
Principle: A beam of electrons are used to create an image in an electron microscope (The John Innes centres, 2013). It allows much smaller objects to be seen in finer detail by being capable of
Principle: Microwaving is a method used for heating of tissue sections and cellular components with the use of a microwave which provides heat by electromagnetic waves that has a high frequency, with a wavelength if one millimetre to one meter and an intermediate between infrared and shortwave radio wavelengths (Miffin, 2002). This allows fast fixation.
Technique: Electromagnetic waves are commonly used for carrying out energy and are said to be powerful for non-invasive processing of materials (Miffin, 2002). The microwave energy offers relatively large specimens to have the ability of good preservation of cellular structure for light and electron microscopy giving it minimal changes to the cellular biochemistry and antigenicity of the specimen (Neuroski, 1994). Microwave stabilization, fast and ultrafast primary microwave-chemical fixation are common methods used to fix specimens (Neuroski, 1994). Irreproducible fixation results may be from the commercial microwave ovens which have limitations (Neuroski, 1994). Microwaving technique is also used for heat-induced epitope retrieval methods where the use of a domestic microwave is not considered since hot and cold spots are common which lead to uneven antigen retrieval, these may also lead to section dissociation because the retrieval may be longer due to the absence of a pressurized environment (Abcam, n.d.). The use of a scientific microwave is more advisable because most of its bands have board vessels that are pressurized having the ability to keep the temperature at a constant 98 degrees Celcius which avoids the dissociation of tissue sections (Abcam, n.d.) .
SCIENTIFIC MICROWAVE
Images for pictures of scientific microwave available from: www.thermoscientific.com
8.2 ELECTRON MICROSCOPY
Principle: A beam of electrons are used to create an image in an electron microscope (The John Innes centres, 2013). It allows much smaller objects to be seen in finer detail by being capable of
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