Test Catageory
فئة التحليل
Hematology
Refrence Books
كتب مراجع
1. Daicw & Lewis Practical Hematology
Skills Required
المهارات المطلوبة
1. Pipetting
2. Colorimetry
Video Resources
مصادر فيديو
Principle
We us Glacial Acetic Acid (GAA) and mix it with blood to brakdown RBCs, Platelets and the Membrane of WBCs . The only thing that remains is the Nucleus of WBCs which is exactly we count, where we can see them under microscope as small Shiny Round Particles.
Equipments
1. 10 – 100 ul + 100 – 100 ul Automatic Pipette
2. Small glss tubes
3. Glacial Acetic Acid
4. yellow and blue tips
5. Colorimeter or Spectrophotometer
Sample Type
EDTA Anticoagulated Sample or Direct Fingerprick using lancet
Procedure
1. Prepare the patient’s finger for blood collection using an alcohol swab in case of collecting finger blood. Allow to air dry and Use a sterile lancet to prick the side of the finger and collect 20μl of blood using a capillary tube or Pipette, “in case of EDTA only collect blood in tube using syringe and mix the sample well”.
2. in clean small tube Add 380μl of glacial acetic acid
3. Add the 20μl blood sample to 380μl of Glacial Acetic Acid in a test tube.
| Test (T) | |
|---|---|
| Glacial Acetic Acid | 380 μl |
| Sample | 20 μl |
Procedure
4. Allow to stand for 2-3 minutes. This lyses the RBCs while fixing the WBCs.
5. Prepare the hemocytometer for counting
6. Mix the lysate again before charging the hemocytometer.
7. Load 10μl of well-mixed lysate under the cover slip on each side of the hemocytometer.
8. Let it stand for 2-3 minutes to allow cells to settle.
9. Count all the WBCs in the four corner squares under 10X objective lens.
10. Take the sum of cells counted on both sides.
Determine the number of cells per microliter by applying the dilution factor:
WBC count = Cells Counted in 4 corners x Dilution Factor(20) /Depth x Area counted
Dilution factor = 20
Area Counted = 4
De[th = 0.1 mm
Normal Range
M. Sulieman
mohammad@mlsgaate.com
Mix sample well before loading to evenly distribute WBCs
Allow samples to settle before counting
Count cells touching upper and left borders only
Handle hemocytometer with care to prevent damage
