Slides for university students are usually prepared in the histology lab. Students in medical sciences are often trained to know what a tissue is when placed on a slide. The essence is for them to be able to identify anomalies or deviations from the standard ones. However, before they can start taking any of the required lectures, the lab technologists must take the tissues through some histology techniques to prepare microscope slides.
There are different types of microscopes used in the lab. They include the light, electron, fluoresce, phase contrast and confocal microscopes. The one to use depends on the slides to view and how requirements available for using them. These microscopes are also different in several ways.
For example, the light microscope has a lamp, the iris, diaphragm, tube with lenses, eyepiece, objective lens and adjustment knobs which of three types: condenser height, coarse and fine knobs. They all perform the function of adjusting the clarity of the slides in view.
If the tissues are not processed adequately, they won't be suitable for learning. This is why the steps involved in the technique must be followed strictly and the composition of chemicals required should be taken note of. The different steps include clearing, waxing, embedding, fixation, dehydration and staining. Using the wrong chemicals in any of these techniques will yield poor results.
Fixation is the first step to take after the death of a cell. It is done to prevent decay since tissues start breaking down immediately after death. The dead tissue is soaked in fixatives such as buffered formalin, Bouin's fluid, and salt. Other ways to prevent decay of tissues after death are refrigeration and heating. When applying fixatives, the ratio should be 3 volumes of fixatives to 1 volume of tissue. This volume must be maintained to make sure the whole tissue is covered.
Dehydration follows after fixation. After fixing, water has to be removed and this can be achieved by using alcohol. However, you should make sure that you use different grades of alcohol in ascending order. The formula, 50%, 50%, 75%, 75%, 98%, and 98% is ideal. The gradual ascent should be followed to remove all bubbles and prevent shrinking due to distortion.
After dehydrating the tissue, the alcohol has to be removed and this can be done by the process called clearing. It can be done with clearing agents such as xylene, benzene, toluene, and chloroform. Afterward, impregnate with wax to remove xylene. Apart from removing the xylene, waxing makes cutting easy and the quality of the cuts to be strong.
The wax must also not be allowed to remain. One way of achieving this is by rehydration. Just like alcohol was used in dehydration, it is also used in rehydration, but this time, the different concentrations are used in descending grades. You should start with absolute alcohol and end in 50% alcohol. This can be followed by the use of water. Afterward, the tissue is stained with some dyes that can aid the identification of its components. Examples are Periodic Acid Schiff, Van Gieson, Osmium tetroxde, Masson trichrome and Sudan black.
There are different types of microscopes used in the lab. They include the light, electron, fluoresce, phase contrast and confocal microscopes. The one to use depends on the slides to view and how requirements available for using them. These microscopes are also different in several ways.
For example, the light microscope has a lamp, the iris, diaphragm, tube with lenses, eyepiece, objective lens and adjustment knobs which of three types: condenser height, coarse and fine knobs. They all perform the function of adjusting the clarity of the slides in view.
If the tissues are not processed adequately, they won't be suitable for learning. This is why the steps involved in the technique must be followed strictly and the composition of chemicals required should be taken note of. The different steps include clearing, waxing, embedding, fixation, dehydration and staining. Using the wrong chemicals in any of these techniques will yield poor results.
Fixation is the first step to take after the death of a cell. It is done to prevent decay since tissues start breaking down immediately after death. The dead tissue is soaked in fixatives such as buffered formalin, Bouin's fluid, and salt. Other ways to prevent decay of tissues after death are refrigeration and heating. When applying fixatives, the ratio should be 3 volumes of fixatives to 1 volume of tissue. This volume must be maintained to make sure the whole tissue is covered.
Dehydration follows after fixation. After fixing, water has to be removed and this can be achieved by using alcohol. However, you should make sure that you use different grades of alcohol in ascending order. The formula, 50%, 50%, 75%, 75%, 98%, and 98% is ideal. The gradual ascent should be followed to remove all bubbles and prevent shrinking due to distortion.
After dehydrating the tissue, the alcohol has to be removed and this can be done by the process called clearing. It can be done with clearing agents such as xylene, benzene, toluene, and chloroform. Afterward, impregnate with wax to remove xylene. Apart from removing the xylene, waxing makes cutting easy and the quality of the cuts to be strong.
The wax must also not be allowed to remain. One way of achieving this is by rehydration. Just like alcohol was used in dehydration, it is also used in rehydration, but this time, the different concentrations are used in descending grades. You should start with absolute alcohol and end in 50% alcohol. This can be followed by the use of water. Afterward, the tissue is stained with some dyes that can aid the identification of its components. Examples are Periodic Acid Schiff, Van Gieson, Osmium tetroxde, Masson trichrome and Sudan black.
About the Author:
When you are searching for information about microscope slides, come to our web pages today. More details are available at http://www.greengeological.com/shop/category/35-microscope-slides now.
No comments:
Post a Comment