Sickle Cell test Using Sodium metabisulphate

Examination of sickle cell is one of the important diagnosis in the medical laboratory, this test is carry on a patient suspected with sickle cell syndrome. The examination can also be conducted where there is malfunction of electrophoretic chromatographic hemoglobin fraction in the position of Hb S. a lot of this investigation has been explained, many kit produce for rapid detection is available. But where are going focus on another simple and easy method of investigating sickle cells that is proven reliable.

Mechanism behind the investigation

Sodium metabisulphate limit tension of oxygen, that turn bring out the abnormal shape of blood different biconcave shape of normal blood.

Material

Bright field binocular Microscope

Cover slip

Glass Slide

Beaker

Reagent

Distilled water

Sodium metabisulphate

Reagent preparation: measure accurately 0.2mg of sodium metabisulphate in 10ml of distilled water, stir the mixture until it all dissolved.

Note that fresh sample reagent must be prepare anytime it must be use.

Method

1. Mix 1 drop of blood with 1 drop of 2% sodium metabisulphate on a microscopic slide
2. Cover with cover slip, and the use candle wax to seal the edge of the slide in contact with cover slip
3. Allowed the prepare sample to stand from 1 to 4 hours
4. Examine under microscope with wet objective lens,

In a sickle cells positive patient, sickle shape of red blood cell will appear like half-moon as shown in the picture below. But on some condition when the sample will not be examine on due time, if it may take 24 hours, the slide should be store in on a moist petri dish.

If the edge of the slide in contact with coverslip is not seal properly or there is reduction in the potency of sodium metabisulphite, false positive result may occur. cause of male infetily and laboratory investigation

Also bear in mind that, positive test never isolate sickle cell trait in a patient, as such special care should be adhere to by examine the preparation carefully at the edge near the coverslip.