Gel coombs card for indirect test

1. Bring the card and Balance to room temperature. Label the card with patient's / donor's name or identification number properly.

2. Remove the foil seal to be ready for testing.

3. Dispense the sample to the saline to prepare a 1% red blood cell saline suspension. Add 50μl of this suspension into the microtubes.

4. Add 50μl serum or plasma into the microtubes.

5. Flick the test card a few times if necessary, make the reactant thoroughly mixed

6. Incubate the card for 15-25 minutes in the 37℃ incubator.

7. After incubation, Centrifuge the gel card(s) in the dedicated Centrifuge at 1500rpm for 4 minutes.

8. After centrifugation, remove the gel card(s) from the centrifuge. Observe, read macroscopically the front and back of each microtube for agglutination and/or hemolysis and record reactions.

Quality Control

The User is recommended to choose the suitable control for Lab daily quality control according to the requirement of specificity and sensitivty in this instruction.

Quality control selection principle is as follows:

Negative Control: Using serum or plasma without irregular antibodies, or using non-sensitized red blood cell. Do the indirectly coombs test. The non-sensitized red blood cell means the red blood cell is negative in the direct coombs test. The serum or plasma of AB type blood can be regarded as the serum or plasma without irregular antibodies

Positive control: Using the serum or plasma with IgG antibodies, and the red blood cell positive to the corresponding antigen, for example, using the 64 times diluted anti-D(IgG) and RhD-positive cells. Do the indirectly coombs test. observe the results is positive or not, and the intensity of positve reaction.