Smear method is a kind of method to make slide specimen by slide mounting method. The preparation method is that the bacteria can be directly coated on the glass slide with bacterial solution, covered with the cover slide for direct observation or dyed after drying. The staining observation usually needs to be observed after washing the staining solution. In order to observe the typical morphology of bacteria, the bacteria in logarithmic growth period should be smeared.
Experimental preparation materials: alcohol lamp, inoculation ring, dye solution, glass slide, strain, normal saline, etc
Steps:
1. take a clean and oil-free glass slide, put it on the flame for several times, take 1 ~ 2 rings of bacterial solution with the cauterized and cooled inoculation ring, and evenly apply it to the center of the slide (diameter 1 ~ 1.5 cm). Note: burn and sterilize the inoculation ring on the flame to ensure that the inoculation ring is sterile.
3. after the inoculation ring is cooled, pick a few colonies from the solid medium, and pay attention not to pick too many colonies to avoid bacterial accumulation.
4. mix the bacterial colonies picked up by the inoculation ring with the normal saline placed on the slide to form a coating surface with a diameter of about 1cm, which should be thin and uniform to make the bacteria present a single-layer distribution. After coating, burn the inoculation ring on the alcohol lamp again for sterilization.
5. drying: the smear shall be naturally dried at room temperature; The specimen can also be heated and dried slightly at a height about 15 cm away from the flame with the specimen facing up. Do not get close to the flame; Or dry it with a hair dryer.
6. fixed smear: heating fixation method is commonly used. The fixation method is to hold one end of the slide with the specimen facing up, and horizontally pass back and forth at the pendulum speed on the outer flame of the flame for 3 times. Note that the temperature should not be too high. It is better to feel hot when the reverse side of the slide touches the skin of the back of the hand.
There are certain requirements for the production of smear, that is, the smear should not be too thick, and the bacteria should be distributed in a single layer in the smear.
