How to make the perfect smear

Smears should be made immediately after you obtain your sample, whether you are analyzing the blood in-house, or sending it to an outside lab.

Step 1:
Place a small drop of blood onto your slide using a hematocrit tube.  

Step 2: 
Place another slide at an angle touching the first slide, right in front of the drop of blood. Back the second slide up and wait until the blood spreads across the edge of the slide.

Step 3:
In a single fluid movement, push the second slide across the first slide, spreading the blood.  The thickness of your smear will depend on the angle at which you hold the second slide with respect to the first and the amount of blood you applied to the slide.

Step 4: 
Be sure to allow the slide to dry completely before staining! Do NOT heat fix the slide!

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Faculty Advisor: Dr. Karen Rosenthal
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Last updated : 5/31/03