In this video I'm going to show you how to make a bacterial smear for endospore staining. But first we need to put on our goggles. Hello! Now we need to prepare our slide for endospore staining. We're going to make a bacterial smear. I start out with a microscope slide that I'm going to make three circles on with a wax pencil. The circle on the left will have my endospore positive sample. The circle on the right will have my endospore negative sample. And the circle in the center will have my unknown. I like to flip my slide over so the wax is on the bottom that keeps the wax out of my bacterial sample. And it's also handy for figuring out which side is the top and which is the bottom. The wax will always be on the bottom and the bacterial sample will be on the opposite side. You may want to label a paper towel with the names of the samples that you'll be putting onto your slide. I'm going to put the silas, an endospore producer on the left, E. coli, a non-endospore producer on the right, and my unknown in the center. I'm going to put a drop of water in each of those circles. I'll use this water to mix my bacterial samples into it. Now I'm going to transfer my bacterial samples onto my slide. I first need to sterilize my inoculation loop. Or one, I put it in the hub of the microincinerator for 5 or 10 seconds. When I remove it, it will be very hot. I need to allow it to cool for another 10 seconds. And then I'm ready to obtain my first bacterial sample. I'm going to start with my negative control E. coli, which does not produce endospores. That's why it's my negative control. I will take my cooled inoculation loop and very gently grab a colony of E. coli off of the plate. Sorry, that was out of the frame. Then I take that sample and I swirl it in the water on the right side of the slide in the right circle. Now I sterilize my loop. I do this between each step 5 to 10 seconds, then allow it to cool. Then I will be obtaining my positive endospore control endospore producer, Bicillus subtilus. I take the cooled sterile inoculation loop and run it across a colony of B-som. Then I mix that sample into the water in the circle on the right side of the slide. This bacteria can stick together, so it might take a little work breaking it apart and spreading it around the circle. Once I do that, I sterilize my wand again. Then I'm ready to obtain my unknown sample. I do the same thing here. Run the cooled loop very gently across the surface of this medium, obtaining a sample. Of my unknown bacteria and swirling that sample into the water in the middle circle on the slide. Then I sterilize my wand for the last time. Now I'm ready to heat fix my bacterial smear. I do this by placing it in the slide holder on top of the micro incinerator. It will need to sit there for about 5 minutes until the water completely evaporates. Heat fixing kills the bacteria and makes it adhere to the slide so it won't rinse off when I stain. Now I'm ready to stain.