• <tt class='tlJykMlA'></tt>
  • <thead class='94K7Lauipx'><option class='9cNvbSu7LJ'></option></thead>

    <em class='jepytdnyfeW3'><b class='oR1Ys12nk'><td class='6rzzLTN'></td></b></em>

  • <dl class='Td0EmkF'><b class='qoWhaibfJ9'></b></dl>

  • <span class='lS1G'></span>

    Heat Fixed Microscope Slide of Bacteria

    How to Prepare a Microscope Slide of Bacteria
    Heat Fixing a Bacterial Smear for Staining


    First, use a wax pencil to draw a circle on the microscope slide to separate each type of bacteria that is going to be sampled.

    If a simple stain of only one type of bacteria, or single mixed sample of bacteria is being prepared, no separation is required.

    Article Summary: In order to view individual bacteria through a light microscope, a bacterial smear must be attached to a slide and then stained. Here is the procedure.
    How to Prepare & Heat Fix a Bacterial Smear 
    Heat Fixed and Gram Stained Slide of Bacteria
    Bacterial smear that has been heat fixed and stained.
    In order to heat fix a bacterial smear, it is necessary to first let the bacterial sample air dry. Then either place the slide in the slide holder of a microincinerator, or pass the dried slide through the flame of a Bunsen burner 3 or 4 times, smear side facing up. Once the slide is heat fixed, it can then be stained.

    How To Prepare a Bacterial Smears

    Heat Fixing the Bacterial Sample
    Before staining, the sample must be heat fixed. This process accomplishes three things:
    • kills the bacteria
    • firmly attaches the smear to the microscope slide
    • allows the sample to more readily take up the stain
    Slides heat fixing on tray attached to microincinerator
    Slides heat fixing on tray attached to microincinerator.
    ​Page last updated 3/2016

    How to Prepare a Bacterial Smear for Gram Staining
    Preparing a Bacterial Smear
    In order to be able to clearly see individual bacteria, a sample of a bacterial colony must be mixed into water or physiological saline. This helps to evenly spread out the bacterial sample.

    Placing the Bacterial Sample on the Slide
    • Place a drop of water into the wax circle that has been created on the slide.
    • Using a sterilized and cooled inoculation loop, obtain a very small sample of a bacterial colony.
    • Gently mix the bacteria into the water drop.

    Instructor's Corner
    Staining Bacteria
    Go to PAGE 2 >

    Photographic guides to differential stains 
    now available!

    1. Gram
    2. Acid-fast
    3. Endopsore

    How to Prepare a Bacterial Smear for Acid Fast Staining
    How to Prepare a Bacterial Smear for Endospore Staining
    Science Image Library Bacterial Stains