Test Method of WBC Count
This article is simply based on the the best methodology for WBC count. It will give you the best and easy means of ascertaining the count of WBC.
- I measured 0.38ml of turk’s solution and dispensed it into a test tube
- I added 20µl (0.02ml) of well mixed EDTA-anticoagulated venous blood and mixed
- I assembled the counting chamber
- I made sure the central grid areas of chamber and the special haemocytometer are completely dry and clean.
I slid the cover glass into position over the grid areas and pressed down on each slide until rainbow colours (Newton’s Rings) were seen prior moistening of the chamber surface on each side of the grid areas will help the cover glass to adhere to the chamber
- I remixed the diluted blood sample, using a Pasteur pipette held at an angle of about 45c, I filled one of the grids of the chamber with the sample, taking care not to overfill the area
- I left the chamber undisturbed in a wet chamber for 2 minutes to allow time for the white cells to settle
- I dried the underside of the chamber and placed it on the microscope stage (using X 10 objective I focused the rulings of the chamber and white cells until they appeared as small b lack dots).
- I counted the cells in the four (4) large corner squares of the chamber marked W1, W2, W3, W4. Total area of 4mm2.
- I recorded the number of white cells per litre of blood using the following calculation;
- Total number of cells counted divided by 2
- Number obtained divided by 10
- Answer obtained from the above X 109/ l this is now the WBC count.