MANUAL PHYSIOLOGY PRACTICAL - Repository:The Medical ...

FM/UOJ
Experiment 9
BLOOD GROUPING
The blood is grouped according the antigen (agglutinogen) found on the
membranes of red blood cells; antigens responsible for the ABO system and the Rh
system are generally identified. They are identified by agglutination of red cells when
reacted with known antibodies (agglutinins).
Instruments:
Blood grouping slide, hand lens.
Reagents:
Anti A (coloured blue), anti B (coloured yellow), anti D (colourless) and Normal
saline.
Method:
Take about 1 ml of normal saline in a small tube and add two or three drops of
blood from a finger puncture and make a red cell suspension. Keep it for five to ten
minutes during which time the blood might clot. Free the red cells from the clot (if
present) by shaking the suspension
Take a drop of each anti- serum on the cavities of the blood grouping slide, as
labeled. Add one drop of red cell suspension to each anti-serum and rock the slide
gently in a circular motion for about ten minutes or till the agglutination is clear make
sure that what appeared is agglutination and neither rouleaux formation nor clotting.
Note
Generally agglutination occurs with anti A and anti B fairly quickly and it is easy
to observe. Agglutination with anti D is slow and does not show clearly. It may be
necessary to wait for 20 minutes and use a magnifying glass.
Precautions:
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Blood
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