Negative staining method

Negative staining is a type of staining procedure where we can observe live cells.


Now dyes are toxic to cells, but here in case of negative staining stains are not taken up by cells, because here the stain use has same charge as the outer layer of cells that repels the stain. We see clear cells in dark background.

Materials

Glass slides

Inoculating loop

Nigrosin or indian ink

Distilled water

Spirit lamp

Procedure
1. Take a greese free slide.
2. Take a drop of water in one side of the slide.
3. Take sample using inoculating loop and mix with the water.
4. Now, take a drop of the ink and mix with the water drop.
5. Take another slide, and touch the edge of the second slide with the drop mix, hold the other slide in 60 degree angle.
6. Now, make a smear by sliding the second slide upon the first slide
7.air dry the slide.
8. Observe under microscope.

Observation and result
White clear cells will be observed against a black background .

Hope this post will help you
                                                (~Bio blog)

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