Explain Procedure for Capsule Staining in a Culture?
We have learnt that Capsule staining can be undertaken either by negative staining or Anthony method. Now carry out the exercise by following the steps enumerated herewith.
For Negative Staining
1. Label the clean non-greasy slide.
2. Put a drop of nigrosin/India Ink dye at one end of the slide and mix it evenly with a loopful culture of given bacterial sample.
3. Spread the mixture over a slide as a thin film with the help of another slide held at 30o angle as illustrated in the figure in margin and pushed away to the other end of the slide.
4. Air dry the smear.
5. Stain the smear with Crystal violet/Safranin for 1 minute and wash gently with water.
6. Finally press the slide with the help of a filter paper and observe under oil-immersion objective of the microscope.
For Anthony Staining Method
1. Take the clean non-greasy slide and prepare a bacterial smear.
2. Air dry the smear and flood the slide with crystal violet for 1-2 minutes.
3. Wash the slide with 20% copper sulphate and gently blot dry it.
4. Observe under oil immersion.