Preparing a Capsule Stain

After doing a negative stain we now are going to do a capsule stain. By doing a capsule stain we are able to see if our bacteria have capsules or slime layers.

We first prepared a smear of bacteria in the Nigrosin stain.

Then after the smear is completely dry we covered it with the Safranin stain for one minute as indicated in our lab book.

After one minute, we gently washed off the excess stain. We had to make sure to avoid removing much of the stain. 

We, then, blot water from the slide with bibulous paper.

We now can see whether or not our bacteria from sample S have capsules or not! 

As you can see under the oil immersion lens of a microscope our bacteria do not have capsules because there is no space between the bacteria itself and the surrounding stain.