Procedure for Making Blood Smears
Procedure for making Blood smears (thin films) :
- To do a blood smear you need two slides. On one slide the blood sample
is placed - this is the "sample" slide. The second slide is used to smear the
drop of blood - this the "spreader" slide.
- Clean the sample slide by wiping it with alcohol. Handle slides by edges
only. (any grease on the slide will cause the dried blood to flake off during staining).
- Place a very small drop of blood near the end of the sample
- Place the end of the spreader slide on the sample slide so that the
short sided edge of the spreader is just below the drop of blood.
- The next two steps should be done quickly to avoid smears that are too
thick. Holding the spreader at an angle of 30o (relative to the sample slide),
push the spreader so that the edge just barely touches the drop of blood. By capillary
action, a thin line of blood will spread along the edge of the spreader .
- Quickly drag the spreader along the entire length of the sample slide in
one fluid motion. Note that the blood is being dragged by the spreader. To view a Quick Time Video of the procedure click here.
NOTE: This is a large file and it is recommended you do not download it
if you are using a modem connection.
- If the correct amount of blood was used, and the technique was performed
correctly, the smear should end before the end of the sample slide. The smear should also
end in a "feathered edge" - a region where the blood cells are well separated.
- Air dry the sample slide. Fix and stain the slide. Various methods may
be used. Normally a commercial staining kit is utilized following the manufacturer's